# ....



## Codyjohns

....


----------



## charveldan

Schweet Broseph ...


----------



## JAC

Nice playing and, a great sounding Major you got there.


----------



## hazmat7719

The boys are back! That is a great sounding amp.


----------



## MartyStrat54

Fantastic as always.


----------



## Codyjohns

....


----------



## MartyStrat54

Why don't you look in your archives and post the gut shots of the chassis.


----------



## Codyjohns

hgh


----------



## mott555

I think I can objectively say that this is the best-sounding amp on the forum.


----------



## Codyjohns

.hh


----------



## StratoMarshall

Holy shit! Eddy and Sammy are creaming their pants for that sound! Dude, that is THE shit right there! Nice work Michael!


----------



## Codyjohns

StratoMarshall said:


> Holy shit! Eddy and Sammy are creaming their pants for that sound! Dude, that is THE shit right there! Nice work Michael!



Thank you so much for checking out the clip, you're very kind Sir.


----------



## Australian

It sounds killer!.....Friedman who?


----------



## NewReligion

Great information and outstanding thread.

David ♫


----------



## CaptainZero

I love your sound!!!


----------



## Codyjohns

Australian said:


> It sounds killer!.....Friedman who?



Thanks Bro !!

LOL I don't think I'm going to put Friedman out of business anytime soon.


----------



## Codyjohns

///


----------



## Codyjohns

CaptainZero said:


> I love your sound!!!



Cheer's Bro !! 

Thanks so much for watching the video.


----------



## mott555

I know using an overdrive is supposed to be bad with these amps. But doesn't the cascaded gain mod accomplish that same thing, and why is that safe? Or does the PPIMV bring the signal levels back down to safe levels for the power amp?


----------



## Georgiatec

The Brown sound....but better


----------



## Codyjohns

nn


----------



## mott555

I'm still not following, but my knowledge of the inner workings of an amplifier is fuzzy at best. I may be in over my head with these questions lol.

Is it because overdrive pedals usually output a waveform that's somewhat square, while the tube distortion from a cascaded preamp is typically smoother with less jagged edges in the waveform? Why does a boost pedal cause the B+ voltage to jump so high?

Just trying to understand, and maybe these questions will help educate others who don't know anything about the Major.


----------



## Codyjohns

vvv


----------



## Valvelust

mott555 said:


> I'm still not following, but my knowledge of the inner workings of an amplifier is fuzzy at best. I may be in over my head with these questions lol.
> 
> Is it because overdrive pedals usually output a waveform that's somewhat square, while the tube distortion from a cascaded preamp is typically smoother with less jagged edges in the waveform? Why does a boost pedal cause the B+ voltage to jump so high?
> 
> Just trying to understand, and maybe these questions will help educate others who don't know anything about the Major.



A quote from old "DAWK" to take with a little grain of salt

"THOSE PEOPLE AT ''MARSHALL'' BACK IN THE DAY DIDN'T KNOW WHAT ''ROCK AND ROLLERS'' WERE GOING TO DO TO THAT AMP...

WHEN A BOOSTER OR SOME KIND OF OTHER PEDAL WAS USED TO MAKE SOME DISTORTION THE (650) VOLTS OF B+ WOULD JUMP TO (1800) VOLTS THAT'S CALLED OVERSHOOT... 

(THE ULTRA LINEAR OPTX CIRCUITS ARE NOT DESIGNED TO HANDLE COMPLEX OVERDRIVE SOUNDS AT HIGH VOLUME LEVELS)...

ONCE THE SIGNAL STARTED TO BUILD UP TO AN SQUARE WAVE THE OPTX STARTED SWITCHING AND ((( BLAM )))...

THE OPTX IS WORKING SORT OF LIKE A ''FLY-BACK'' TRANSFORMER IN A TV SET,,, THAT WHAT'S PRODUCING THAT HIGH ''IPV'' VOLTAGE... 

IT'S LIKE TURNING OFF A WATER FAUCE AND HEARING THAT ''BANG''...

(IF IT WASN'T FOR THE HIGH QUALITY OF THOSE ''ENGLISH'' (KT-88'S) THAT AMP WOULD HAVE BEEN DEAD IN THE WATER...

THEN THE (B+) @ (1800) VOLTS WOULD ''ARC'' OVER TO THE CLOSEST GROUND,,, USUALLY BETWEEN PINS (2) AND (3) ON THE OUTPUT TUBES...

THAT CAUSES A LOT OF SMOKE,,, BURNING OF THE TUBE SOCKET AND A REAL BAD SMELL... 

''THUS LEAVING A ''BIG'' BLACK ULGY CARBON MARK INSIDE THE CHASSIS WHERE IT ARCED''...

''THIS WOULD HAPPEN SO FAST THAT IT DIDN'T HAVE TIME TO BLOW THE FUSE..."


----------



## Codyjohns

//


----------



## Codyjohns

nnn


----------



## Valvelust

Michael RT said:


> I learned all I know about the Major from John "Dawk" Stillwell.
> 
> When it comes to the Major, Dawk is the best guy to direct your extreme technical questions too.
> 
> Here's the link. www.dawksound.com - Home



Yes I've got list of parts and info copied and stashed as you know he took them down and wont offer direct his mods any longer after a fallout with a member


----------



## Valvelust

Michael RT said:


> I learned all I know about the Major from John "Dawk" Stillwell.
> 
> When it comes to the Major, Dawk is the best guy to direct your extreme technical questions too.
> 
> Here's the link. www.dawksound.com - Home



Yes I've got list of parts and info copied and stashed as you know he took them down and wont offer direct his mods any longer after a fallout with a member several years ago


----------



## Codyjohns

\hj


----------



## Valvelust

Michael RT said:


> Yeah I know that....... that makes me probably the only person on the net sharing Major gain mods.
> 
> Thank goodness it's a very rare amp series from Marshall or I'd be swamped with questions.



I've got a Major PA that I want to set up with different voicing on the channels so I'm about to tear into it


----------



## Codyjohns

nnm


----------



## Valvelust

Michael RT said:


> That sounds like fun.
> 
> I would love to know how things go for ya, keep me posted.



Any suggestions appreciated!


----------



## Codyjohns

Valvelust said:


> Any suggestions appreciated!



What kind of sound are you looking for ??

Do you want the amp to growl ??


----------



## Codyjohns

m,,


----------



## MartyStrat54

Michael. Did you see this one?

http://www.marshallforum.com/lets-t...an-you-tell-me-about-marshall-major-head.html

http://www.marshallforum.com/lets-t...t-can-you-tell-me-about-marshall-cabinet.html


----------



## Codyjohns

m


----------



## Codyjohns

///


----------



## Valvelust

Michael RT said:


> What kind of sound are you looking for ??
> 
> Do you want the amp to growl ??



Yes and also to the other end a more saturated sound but since I have all those channels I would like to make them each different.


----------



## Codyjohns

,,


----------



## Codyjohns

,.


----------



## Valvelust

Me?? or ?? LOL

I haven't played this baby for awhile. It's not the prettiest Major and can't remember how "cobbed up" the guts are but I'll get some pics shortly. And no I won't be drilling any holes!


----------



## Codyjohns

Valvelust said:


> Me?? or ?? LOL
> 
> I haven't played this baby for awhile. It's not the prettiest Major and can't remember how "cobbed up" the guts are but I'll get some pics shortly. And no I won't be drilling any holes!



I would love to see pic's !! 

I believe you have 3 Majors 

The other two models are ???


----------



## Valvelust

Michael RT said:


> I would love to see pic's !!
> 
> I believe you have 3 Majors
> 
> The other two models are ???



Yup two other 1967's
This one is kinda special with a PPIMV and NOS vintage Gold Lion glass. It sat in a studio in Burbank with groups such as Stones, AIC, Chili Peppers etc. recorded many albums and this amp had been used in some of those songs.
The cab is a 1970 mdl 1981 4X15 (cast frame greenbacks)


----------



## Codyjohns

Valvelust said:


> Yup two other 1967's
> This one is kinda special with a PPIMV and NOS vintage Gold Lion glass. It sat in a studio in Burbank with groups such as Stones, AIC, Chili Peppers etc. recorded many albums and this amp had been used in some of those songs.
> The cab is a 1970 mdl 1981 4X15 (cast frame greenbacks)



Beautiful amp and cab !! 
Prefect speakers for this amp.
The Major preamps sound soooo great cranked up and tamed with a PPIMV.

You can't go wrong with that setup.

More  please !!


----------



## Valvelust

Michael RT said:


> More  please !!


----------



## Codyjohns

bb


----------



## Valvelust

Michael RT said:


> That is glorious, it looks like you have '69 Major Plexi (model# 1967) and it's mint.
> 
> Those power tubes are worth big-bucks, I wish I had a set.
> 
> Thank you for taking the time to post the pic's.
> 
> I found with my '68 Major Plexi the PPIMV mod was still not a enough gain for me but with "the one wire mod" add with the PPIMV the amp head just screamed over the top "tons of gain".
> 
> I like the one wire mod because it's just adding a piece of wire and a 1meg resistor, very simple mod without harming the value of the amp head.



This amp I've just left alone, pulled it once to take a peek and put it back.

Here is the back side of the cab....let me tell ya, those babies will make the hair on your legs dance


----------



## Codyjohns

What a monster !! 

I can't believe the condition of the cab and speakers, it's like new. 

It must sound awesome with the Major cranked up.

I want one of these cabs.


----------



## Valvelust

Michael RT said:


> What a monster !!
> 
> I can't believe the condition of the cab and speakers, it's like new.
> 
> It must sound awesome with the Major cranked up.
> 
> I want one of these cabs.



They are a breed of their own for sure and have a unique spectrum of the way they project guitar.

Put the Major and this beast together and we have a whole new world of Marshall few get to experience...


----------



## Codyjohns

...


----------



## Valvelust

Michael RT said:


> I totally agree with ya, we own some of the rarest equipment Marshall has ever made.
> 
> I hope to experience the 4x15 cab with my Major one day.
> 
> I can imagine it would sound just amazing, the headroom would be incredible.



Not only the headroom but the way they take those notes at certain frequencies and give them character where a 12" wont


----------



## Codyjohns

[,,


----------



## Codyjohns

//


----------



## Valvelust

Laptop speakers don't quite cut it...

You do have the chops!


----------



## Codyjohns

mm


----------



## Codyjohns

jmk


----------



## Valvelust

Michael RT said:


> Hopefully those who are suffering from G.A.S. won't venture into this thread.
> 
> J/K



no sh_ _! haha

Here's the PA Beast


----------



## Codyjohns

,.


----------



## MartyStrat54

Valvelust-You have a very rare 415 cab. Those 15's are fantastic. I worked in a pro audio repair shop in Phoenix and I only came across that cab two times. Don't ever damage one, as you'll never get a suitable recone. 

Thanks for sharing your rig and your amp stash.


----------



## Valvelust

MartyStrat54 said:


> Valvelust-You have a very rare 415 cab. Those 15's are fantastic. I worked in a pro audio repair shop in Phoenix and I only came across that cab two times. Don't ever damage one, as you'll never get a suitable recone.
> 
> Thanks for sharing your rig and your amp stash.



Thank you!
Yes I always wanted the 15's and then to go with a major I had just bought, I caught this for sale down at Andrews amp lab a few years ago.. Jeff was great and it actually was quite an amazing find and also an amazing feat to get it packed properly and shipped here from Georgia to Oregon through FEDX as if I remember it made it by 1/8" for max. 

They are some fantastic special speakers and always keep my eyes open for them.


----------



## MartyStrat54

If you ever get the time would you post a picture of the back of the speaker so everyone can see the info?


----------



## Valvelust

MartyStrat54 said:


> If you ever get the time would you post a picture of the back of the speaker so everyone can see the info?



I had this on file but not the greatest


----------



## Codyjohns

Check out this find.
I wish I had the money right now, damn.

1969 Marshall 4x15 cab (Holy Grail) rare... - City of Toronto Musical Instruments For Sale - Kijiji City of Toronto Canada.


----------



## MartyStrat54

Those were rated at 50 watts, correct?


----------



## Codyjohns

MartyStrat54 said:


> Those were rated at 50 watts, correct?



Yeah I'm pretty sure they are, you'd think they would be rated higher being 15".


----------



## Valvelust

MartyStrat54 said:


> Those were rated at 50 watts, correct?



I'll get a better picture up soon.
They are G15M 50 watts 55Hz 16 ohm


----------



## AlvisX

Michael RT said:


> Yeah I'm pretty sure they are, you'd think they would be rated higher being 15".



Back in those days that was "hi-power"......


BTW your amp sounds killer .....like it could launch a man to the moon ...


----------



## stilllifer

Michael RT said:


> Check out this find.
> I wish I had the money right now, damn.
> 
> 1969 Marshall 4x15 cab (Holy Grail) rare... - City of Toronto Musical Instruments For Sale - Kijiji City of Toronto Canada.



Michael. I posted the link to this in the Classifieds...outstanding looking cab. The guy actually said he'd trade me this cab + $800 for my 1960B with original G12-65's...tempting but I don't have $800 at the moment...


----------



## Codyjohns

AlvisX said:


> Back in those days that was "hi-power"......
> 
> 
> BTW your amp sounds killer .....like it could launch a man to the moon ...



That's so true Alvis, I was thinking that after I post the comment. 

I really appreciate ya checking out the clip, this amp is like a monster with all the headroom it has.


----------



## Codyjohns

stilllifer said:


> Michael. I posted the link to this in the Classifieds...outstanding looking cab. The guy actually said he'd trade me this cab + $800 for my 1960B with original G12-65's...tempting but I don't have $800 at the moment...



I totally agree with you, outstanding cab. 

I'm in the same vote as you, don't really have the money right now for more gear.


----------



## Codyjohns

mm


----------



## jack daniels

I posted this in your other thread but here it is. I've got one of two output tube types for you to try, check them out.

https://www.tubedepot.com/products/t...er-vacuum-tube

AND

https://www.tubedepot.com/products/t...er-vacuum-tube


----------



## Codyjohns

jack daniels said:


> I posted this in your other thread but here it is. I've got one of two output tube types for you to try, check them out.
> 
> https://www.tubedepot.com/products/t...er-vacuum-tube
> 
> AND
> 
> https://www.tubedepot.com/products/t...er-vacuum-tube



That's really cool, those KT150's has got my attention. 

Have you tried these power tubes out in any guitar amps before ??


----------



## jack daniels

Michael RT said:


> That's really cool, those KT150's has got my attention.
> 
> Have you tried these power tubes out in any guitar amps before ??



No, because I don't require that much power and headroom however, you may have given me an idea. I also own a Traynor YBA200 bass head w/matching cabinet that COULD benefit from a KT120 or KT150 swap.


----------



## jack daniels

As the description of these tubes iterate, it's important that one find out what their amp's filament supply is capable of delivering prior to their purchase of either one of these tubes.


----------



## Codyjohns

..


----------



## jack daniels

If you want you're amp to run cooler, have more power and headroom, want tubes that can handle screen grid voltages, and take less risk of arcing and zapping your original OT it's definitely a head scratcher isn't it?


----------



## Codyjohns

,..


----------



## Codyjohns

,,


----------



## AntonPlaysRock

Nathan Brown said:


> I could do a 200W Major combo!



What would the point of that even be?


----------



## damienbeale

AntonPlaysRock said:


> What would the point of that even be?



...and who the **** could lift it off the ground!


----------



## damienbeale

Nathan Brown said:


> Simple, use castors.



Castors carry the amp around for you and lift it in and out of the car for you do they?

The whole idea is just plain stupid. A major head on it's own weighs more than your frontline combo. Add a rugged cabinet and two huge speakers (or four not so huge ones) and you have got possibly the most ridiculous combo ever made by anybody anywhere.

There is usually a good reason why certain things have never been done before.


----------



## Valvelust

Nathan Brown said:


> I'd get a Superlead or something and do the same mods. Or I would build my own circuit based on the Major. Got a schematic on the computer. but I don't have a PCB. Hmmmmm..... I could do a 200W Major combo!






:frown:


----------



## Codyjohns

damienbeale said:


> Castors carry the amp around for you and lift it in and out of the car for you do they?
> 
> The whole idea is just plain stupid. A major head on it's own weighs more than your frontline combo. Add a rugged cabinet and two huge speakers (or four not so huge ones) and you have got possibly the most ridiculous combo ever made by anybody anywhere.
> 
> There is usually a good reason why certain things have never been done before.



Yeah I agree, can you imagine taking a Major combo up & down a flight of stairs.


----------



## damienbeale

Even my 1960TV A cab is bad enough. But I'd still rather carry that than my old 2X12" 4104 combo. A major combo is just unthinkable. The cabinet would have to have some serious bracing too. I can feel a hernia coming on just thinking about it.


----------



## Codyjohns

The Marshall Major is a roadies nightmare.


----------



## Codyjohns

Nathan just buy a late 70's JMP 2x12 combo and stop dreaming.


----------



## levelx43

Nathan Brown said:


> ... an A chord but without the B string on the chord. That was a chord I recently learned ...



Isn't that a variation of an A5 chord?


----------



## Codyjohns

//


----------



## Appetite4distortion

Why limit yourself with 4x15" 200w combo? Go the extra mile, full-stack-combo, 8x15"


----------



## Marshall Art

Michael RT said:


> So anyways back on track,
> 
> V3 (12AU7 or 12AT7) in the Major is really not a phase inverter, it's a parallel gain stages for a differential signal.
> The Major's PI is the second half of the second 12AX7. It's called a "cathodyne" or split load.
> 
> The 12AU7 (or in my case 12AT7) get 350v and usually higher on it's plates.
> The 12AX7's don't run efficiently with this type of voltage on it's plates and can cause damage to the amp.
> 
> Because of the 12AU7 in V3, there is a large gain loss.
> 
> So to make this amp growl over the top and make it plug and play at any volume, you have to install a PPIMV mod.
> 
> Because of V3 in a Major, I like to add "the one wire mod" as well.
> cascade (series)
> The amp really screams in series instead of in parallel (stock)



You should charge people for reading this post.


----------



## Codyjohns

Marshall Art said:


> You should charge people for reading this post.



I was just trying to keep the theme of the thread rolling and thought it was time to talk about some important facts about this ultra-linear amp design. (free of charge)


----------



## damienbeale

A thousand facepalms wouldn't be enough...


----------



## Codyjohns




----------



## AlvisX

Aside from the tomfoolery......that was some useful info .I never studied the Major circuit with any depth ,to know that v2-v3 stuff ....enlightening (which is what *I* perceive this forum to be about) THANKS Michael

I've always been more interested in the Major as a bass amp than anything else....
My straight 100 watters are WAY too loud for guitar already. I only use 'em outdoors these days .If I do use _them_ inside ,it's almost always for bass


----------



## Appetite4distortion

I have a 1971 major "1978" bass circuit, that I use with a germanium treblebooster and a strat in a Deep Purple tribute band (it' s the "made in Japan" setup used by Blackmore before switching to lead majors in '74).
It's totally stock and without a boost is honestly not that louder than your typical 100W amp: it's moore clean "oomph", and in its stock form it does not crunch "seriously" if not at earthquacking volume levels. "1967" lead models push the front end earlier.
The beauty of this amp IMO is its natural compression and sustain on clean and crunch sounds, and how complete and lushy they are. Like a Fender Twin on steroids, crossed with a Hiwatt but with enough of that gnarly marshall mids.
On a typical superlead with split cathode preamp, the clean sounds are slimmer and plinky, you can feel amp is clearly calling for higher crunch levels to "fill" the bass.
On the majors the output tubes provide more compression than saturation. 

These clips prove this design works equally well in a hi gain application too thanks to the clean and powerful OT stage, you can pump the preamp and it will never sound fizzy!
That's similar concept I think like in the 80s many used hi gain preamps (or, a plexi to 10 and then in a dummy load) and then slammed into huge SS poweramps, to have definition and depth of sound (and also you could do wet/dry/wet).
Major however have their own character, not so neutral like SS amps-so it's very good for a pumped plexi tone with lot of depth and character!


----------



## Codyjohns

//


----------



## damienbeale

Appetite4distortion said:


> Why limit yourself with 4x15" 200w combo? Go the extra mile, full-stack-combo, 8x15"


Hmmmm, I have a feeling I recognise that truck...

Nope wait, I think the one at Marchwood was bigger. Numpty's did this THREE TIMES to the same truck.


----------



## damienbeale

Nathan Brown said:


> Besides, I love the way your Major sounds and I want to sell these off based on your modifications and price them at $1,245.00 so you'd be getting a good deal of a Major.




So you don't think not having any qualifications or liability insurance might not get in the way of this then?

Let alone that you would barely be able to buy the components and raw materials to build a Major head for $1245 Aus.


You really need to stop dreaming, and wake up to reality. Nobody wants to build and sell Majors because they are a liability. It's easy to mis-use them and blow them to smithereens. Warranty periods have to be honoured by law. It is the stupidest idea that anyone could come up with.

Michaels mods do not make the amp more stable, or safer, merely easier to get great tone at lower volumes.


----------



## Codyjohns

It's just a "68 trailer queen" but I love it.


----------



## damienbeale

Michael RT said:


> It's just a "68 trailer queen" but I love it.


I'd love one too. But I don't think I'd ever take one out on stage. Gigs are too unpredictable.


----------



## Codyjohns

damienbeale said:


> I'd love one too. But I don't think I'd ever take one out on stage. Gigs are too unpredictable.



Yeah, I agree. 

I'm just using mine for home recording or maybe in a studio soon. 

My Major would make a great house amp for any decent studio.


----------



## AlvisX

damienbeale said:


> I'd love one too. But I don't think I'd ever take one out on stage. Gigs are too unpredictable.



That's why I like to have a cheap solid state peavey bass head around ....just in case 

Speaking of fire extinguishers ......I forgot, not to encourage any nonsense , but I _did _whip up a homebrew "major" a few years ago in Europe 

I found this amp at a place in Northern Germany where I started buying gear back in '02. I didn't know what it was. Had no logo or brand markings on it . I just saw 4x el34's thru the top vent .I thought it was a Stramp ,the price was right ,so I bought it 

Got it back to my then tour base in Switzerland and opened it up . Had a huge ass unsafe lookin pwr tranny and a giant UL output ......."But hey where are the rest of the fckn tubes ?" It had one 12ax7 ,which I figured was a PI ,but that was it ....turns out the sumbich had a transistor preamp I was bummed. The guys at the store said they had no idea and offered to take it back , but _Mr. Up For The Challenge _decided to keep it.I dont remember what I was thinking . But somehow a idea came together 





There was a metal cowling shielding the transistors that I visualized mounting a couple tube sockets on and a tag board .So I took that cowling back to the USA with me and got started. I wired up a *bassman* preamp which would basically "plug in" to the existing PCB mounted phase inverter . So the next time I went to Europe ,I took the new preamp back with me & wired it in . 12ay7 in v1 , a 12at7 in the PI and 4 x 6550 





In the meantime I found out the brand name was Maquis, a name given to French guerrillas who fought the Nazis in WWII. I could totally dig that in that Im all for fightin Nazis AND I've been described in my PR as a"Garage Guerrilla" due to my tendency to use DIY music gear ......

http://www.radiomuseum.org/r/schumannkg_maquis_gv150gv_15.html





So I got it all put together ,plugged it into a stack of JCM 800 1935 cabs on one end , p-bass on the other end . In a true Frankenstein moment ....threw the standby ........SHE's ALIVE! Big bouncy round bottom rock n roll bass 

Last thing was the back panel , which was completely solid ....there is a top vent ,but i could use more ventilation . I found some steel mesh at the Swiss hardware store & started cuttin 





While we were on the road with Gary Moore one of the old filter cap let go in mid set .Luckily we had a Markbass hybrid head standing by 
It was down for about 2 days ...me fixing it in a hotel room on a day off. Germny has some great electronic component stores ......fckn V2 rocket parts , hell yeah , I really felt like a scientist


----------



## Codyjohns

Thanks for sharing that Alvin. 

That's a really cool amp. 

That's what I want to do one of these days, pickup a decent bass rig.

I enjoy playing the bass now & then.


----------



## AlvisX

Michael RT said:


> Nathan just buy a late 70's JMP 2x12 combo and stop dreaming.



If ever there was a guy in need of a Lead 12 ....I think he's it 

Or perhaps .....

Dummy Empty Marshall Plexi Superlead Head (head box with no amp in it ) | eBay


----------



## damienbeale

Don't be daft. It's way overpriced. Even with an empty chassis and rear faceplates it'd still be overpriced


----------



## Codyjohns

AlvisX said:


> If ever there was a guy in need of a Lead 12 ....I think he's it
> 
> Or perhaps .....
> 
> Dummy Empty Marshall Plexi Superlead Head (head box with no amp in it ) | eBay



I think he should start here first.


----------



## Codyjohns

I like the way this picture turn out.


----------



## damienbeale

Ugh, on a big screen I can now see just how rough that red dummy headcab is. Recovered badly in godknowswhat. That's a £30 piece of junk if ever I saw one.


----------



## Codyjohns

damienbeale said:


> Ugh, on a big screen I can now see just how rough that red dummy headcab is. Recovered badly in godknowswhat. That's a £30 piece of junk if ever I saw one.




Dude, I think the joke went right over your head.


----------



## Blokkadeleider

I like the fact that that amp still seems to have it's original impedance selector. 
How is the mains connector, Bulgin?


Gr,

Gerrit.


----------



## mickeydg5

AlvisX said:


> If ever there was a guy in need of a Lead 12 ....I think he's it
> 
> Or perhaps .....
> 
> Dummy Empty Marshall Plexi Superlead Head (head box with no amp in it ) | eBay


 


Michael RT said:


> Dude, I think the joke went right over your head.


Ahh, haa, haa, ha.


----------



## damienbeale

Michael RT said:


> Dude, I think the joke went right over your head.




Most of them do.

But alas, this was just my rubber brain going off on tangents.


----------



## Codyjohns

Blokkadeleider said:


> I like the fact that that amp still seems to have it's original impedance selector.
> How is the mains connector, Bulgin?
> 
> 
> Gr,
> 
> Gerrit.



Yip. original impedance selector.

No, I don't have the disconnect main in mine, it's hard wired internally.

Most of the '68 Majors I have seen were hard wired mains.

Here's a picture of another '68 Major, looks more stock.


----------



## wakjob

So, 715p Polypropylene capacitors... Concertina PI @ v2.... Beam Power Tubes...

I think Leo would have approved of this amplifier.


----------



## Codyjohns

wakjob said:


> So, 715p Polypropylene capacitors... Concertina PI @ v2.... Beam Power Tubes...
> 
> I think Leo would have approved of this amplifier.



I love the sound of those orange drops. 

Concertina (split-load) PI, I think it's very similar to the fender tweed design. 

Tetrode


----------



## wakjob

Michael RT said:


> I love the sound of those orange drops.
> 
> Concertina (split-load) PI, I think it's very similar to the fender tweed design.
> 
> Tetrode



Been fooling around with my Fenders lately. I'm really warming up to the OD caps.

Oh yeah, cathodyne PI's are what gave a lot of the old Orange & Hiwatt amps their sound.

If kt88's are the same construction as 6550's, then yeah, they are both beam tetrodes.


----------



## Codyjohns

wakjob said:


> Been fooling around with my Fenders lately. I'm really warming up to the OD caps.
> 
> Oh yeah, cathodyne PI's are what gave a lot of the old Orange & Hiwatt amps their sound.
> 
> If kt88's are the same construction as 6550's, then yeah, they are both beam tetrodes.



KT88 is a beam tetrode. 
It a kinkless tetrode, that's what the "KT" stands for.


----------



## AlvisX

Scored a Major Plexi PA .........of course modded 
But not all bad Channel 1& 2 are normal .He stuck some kind of master in ch1 vol hole. Gonna have to look under the hood and see if that's cool or not 

And looks like someone did some kind of cascade thing with the tube on Ch 3&4 . Haven't been able to crank that mod channel yet to see if it has a sweet spot . Right now it sounds somethin like stock 2204 brite cap values (which I dont like) But if its a good job ,I may just tweak it for TONE ,rather than obsess about it not being stock

NOW, the reason I even care about a Major ......BASS ! I plugged my Gibson SB-450 into the un-modded channels .......perefct ! And this is outa my 65 equipped Jubilee cab ...not even out of a proper bass cab yet . I'll probably put a 12ay7 on that channel....killer bass tone


----------



## Codyjohns

That's awesome Alvin, Congrats !! 

What year is it ??

You could probably set the amp up to play lead guitar through one channel and bass through the other. 

If you get a chance, please post some pic's.


----------



## AlvisX

Michael RT said:


> You could probably set the amp up to play lead guitar through one channel and bass through the other.



Yeah ,Im guessin that was the intent of the mod .....although I dont think the "lead" channel sounds very good ....a little gain-y ,in an uncontrollable way.....but I can tweak it for some tone 
He threw a rotary switch back there for an impedance selector ....not tooo sure about that 

Still haven't opened it up to look at the work (maybe better to wait til it fails ) Sprained my ankle last week so I dont feel much like liftin this chassis ....

My phone cam is broken so pics not very good but here's a couple starters


----------



## Codyjohns

AlvisX said:


> Yeah ,Im guessin that was the intent of the mod .....although I dont think the "lead" channel sounds very good ....a little gain-y ,in an uncontrollable way.....but I can tweak it for some tone
> He threw a rotary switch back there for an impedance selector ....not tooo sure about that
> 
> Still haven't opened it up to look at the work (maybe better to wait til it fails ) Sprained my ankle last week so I dont feel much like liftin this chassis ....
> 
> My phone cam is broken so pics not very good but here's a couple starters



Thanks so much for posting the pic's, it looks like a '68. 
Holy Grail Material my friend. 
I hear ya about pulling the chassis, what a bitch it is taking this thing in & out of the box. 

When you do take out the chassis, please post some pictures.
I want to see what's going on in there.


----------



## AlvisX

Used the beast for last nite's gig ....The bass rig from Hell,with a Marshall DBS series 2x15 cab ..Murder !

Hey Michael, did yours come with a back panel ?


----------



## Codyjohns

AlvisX said:


> Used the beast for last nite's gig ....The bass rig from Hell,with a Marshall DBS series 2x15 cab ..Murder !
> 
> Hey Michael, did yours come with a back panel ?



Yeah, the Major's just do everything awesome. 

No mine didn't come with a back panel, I bought a replacement panel at mojotone.

http://www.mojotone.com/amp-parts/B...Head-Backpanel-w-Gold-Metal-Mesh#.U2a5nYFdUdw


----------



## AlvisX

Michael RT said:


> No mine didn't come with a back panel, I bought a replacement panel at mojotone.
> 
> Mojo Back Panels; Marshall Style Large Box Head Backpanel w/ Gold Metal Mesh



Cool , I was thinkin about mojotone . I need 3 back panels ......WhoTF loses a Marshall back panel .....?

Hey you guys ,we have a cabinet called MA....


----------



## Codyjohns

LOL, You should call that rig "Big MaMa".


----------



## Valvelust

AlvisX said:


> Cool , I was thinkin about mojotone . I need 3 back panels ......WhoTF loses a Marshall back panel .....?
> 
> They take em off to keep em cool and forget where they put em....


----------



## Codyjohns

Valvelust said:


> They take em off to keep em cool and forget where they put em....



It could be a sign that a lot of amps are not biased properly.


----------



## Valvelust

Michael RT said:


> It could be a sign that a lot of amps are not biased properly.



I know my '73 Orange OR120 even biased conservative runs like friggin pizza oven where the back is burnt and brittle, You see a lot of those with missing panels...


----------



## Metroman

I almost bought 1 ( Marshall Major ) last week off of Ebay for 3295 but got a slightly used ( -20 hours ) Metro GMP45 Limited Edition with NOS tubes mustard caps ect for 2450. 1200 or so less than brand new.

I im not capable of modding the Marshall so I got the Metro.

I probably could have had Richie or Dana Hall mod it for me as I live 10 minutes away from Hallamplification and have known them most of my life.

Its a Purple 200 Watt Major and looked in really good shape for 1968. Nobody bought the Marshall and if anyones interested a guy at ebay bkparks has it. I have no affiliation.


----------



## Codyjohns

Metroman said:


> I almost bought 1 ( Marshall Major ) last week off of Ebay for 3295 but got a slightly used ( -20 hours ) Metro GMP45 Limited Edition with NOS tubes mustard caps ect for 2450. 1200 or so less than brand new.
> 
> I im not capable of modding the Marshall so I got the Metro.
> 
> I probably could have had Richie or Dana Hall mod it for me as I live 10 minutes away from Hallamplification and have known them most of my life.
> 
> Its a Purple 200 Watt Major and looked in really good shape for 1968. Nobody bought the Marshall and if anyones interested a guy at ebay bkparks has it. I have no affiliation.



Do you have an ebay link, I'd loved to see the '68 Major. 
There's not many '68 Majors left in the world and I'm trying to account for how many are left in existence. 

I'm guessing their's only about 40 left out of the 150 that were made that year. Most of the '68 Majors have blown up unfortunately.


----------



## Tone Slinger

I know that a George Metropoulos JTM 45 clone is an amazing thing.........but, you had the dough to procure a '68 Plexi Major.......I DEFINATELY would have went that way. Listen to MichaelR/T's clips for sonic verification as to how BADD ASSED that amp is


----------



## Codyjohns

Tone Slinger said:


> I know that a George Metropoulos JTM 45 clone is an amazing thing.........but, you had the dough to procure a '68 Plexi Major.......I DEFINATELY would have went that way. Listen to MichaelR/T's clips for sonic verification as to how BADD ASSED that amp is



and $3,295 is a good price for a '68 Plexi Major, they can run as much as $4,000 to $5,000 depending on the condition.


----------



## Metroman

This 1 looked to be in really good shape.

Here is the link. And I have 0 idea if it has been modded ect.

1968 Marshall Major Plexi with Purple Tolex eBay

I got the Metro for $2450 and over $1300 in NOS GEC KT66's and Mullards alone. Less than 1 year old and only 20 hours on it. This Metro I got costs about 4000 with all NOS tubes and caps so I got the Metro at about 1500 off.

so I got the amp for 1000 and the tubes were 1350 =2450 and that included shipping from California to Ky.

I feel I got the best deal on an amp Ive ever got. It sounds wicked through 2 JBL E120's with Hemp cones.


I also have 4 different cabinets to run it through... Or at least I will when I get the bottom cabinet of the Metro GMP 45/100

I have 2 x 15 Altec 418-8h... a 4 x 12 with JBL E120's and 2 x 1 x 12 Theile type cabinets for JBL E120's with hemp cones. These also have a 3 piece back and can be used semi open, open, sealed or ported. They are 100% 3/4 in. Baltic Birch inc. baffle.

at the end of summer I will get the empty bottom cabinet of the Metro GMP 45/100 for 4 x 12 1972 Celestion G12M with Pulsonic cones

I just got the speakers in the mail today from another member here. They are in mint condition.

The funny thing is when I was when I found this amp ??

I was looking for an Acoustic Guitar. A really nice 1. 3500 dollar-4000 range.

I saw this amp and bought it on the spot.

I then came and registered here to see any reviews on the Metro and saw the 4 celestions and jumped on them.

I had seen the Premier Guitar JTM45 shootout from 2009 and while all amps were good . they said the 2 metros sounded the most like the original control amp which was a 65 JTM45. And Ive seen nothing but good? Great reviews on Metro

It will be a while before I get an acoustic now.

a friend of mine has the Very First 1967 10,000 series Plexi sold in West Virginia. and also his 1 owner 62 Les Paul with the Vibrola.

The Amp came from Mack and Daves in Huntington WVA.


----------



## Codyjohns

This is the only '68 Major on ebay that I can find and it's not purple.

1968 Marshall Major Plexi Vintage Sound OF Choice 200 Watts Year | eBay

Do you have a ebay link of the purple '68 Major ??


----------



## Metroman

copy and paste this in google search engine........ 1968 Marshall Major Plexi with Purple Tolex eBay


The sale is over and nobody bought it.

here is the info he provided.



Detailed Item Description 
The amp that is for sale in this auction is of the second series variant made in 1968, the Marshall Major with plexiglass front and rear chassis panels and “Marshall Major” silk screened on the back panel. This amp has a reproduction head cabinet covered in purple Marshall tolex with a recent small gold 6 inch Marshall logo, period correct replacement reissue Marshall control knobs. Transformers are 100% original. Speaking of transformers, the transformers on the Marshall Majors are absolutely massive and are the heart of the loud, punchy, chest-pounding volume that only a Marshall Major can deliver. Over the amps 46 year lifetime, a few capacitors, resistors, and normal channel volume potentiometer have been replaced; this type of maintenance is not unexpected given the age of the amplifier. The back right of the chassis where the power chord is attached is slightly dented, but this does not create a problem at all with the amps operation and could be easily straightened back out once the plexi rear panel is moved. Also, I believe the two speaker out jacks have been replaced along with a couple of the switches on the front panel and maybe the fuse holders or fuse holder caps(?). As for the tonal description of this amplifier… it has all of the classic Marshall plexi era tone… only louder… and I do mean LOUDER!! This is by far one of the loudest amps I have ever heard, and more importantly, FELT. The additional power will make your speakers move some air. If you happen to be running this through a vintage Marshall 4x12 cabinet loaded with 25watt Celestion Greenbacks, I would strongly advise that you hook up two cabinets to this head so that you do not accidentally blow any speakers… it is that powerful and has tremendous output available. Plain and simple, this is a full grown man’s amp.


----------



## Codyjohns

Metroman said:


> copy and paste this in google search engine........ 1968 Marshall Major Plexi with Purple Tolex eBay
> 
> 
> The sale is over and nobody bought it.
> 
> here is the info he provided.
> 
> 
> 
> Detailed Item Description
> The amp that is for sale in this auction is of the second series variant made in 1968, the Marshall Major with plexiglass front and rear chassis panels and “Marshall Major” silk screened on the back panel. This amp has a reproduction head cabinet covered in purple Marshall tolex with a recent small gold 6 inch Marshall logo, period correct replacement reissue Marshall control knobs. Transformers are 100% original. Speaking of transformers, the transformers on the Marshall Majors are absolutely massive and are the heart of the loud, punchy, chest-pounding volume that only a Marshall Major can deliver. Over the amps 46 year lifetime, a few capacitors, resistors, and normal channel volume potentiometer have been replaced; this type of maintenance is not unexpected given the age of the amplifier. The back right of the chassis where the power chord is attached is slightly dented, but this does not create a problem at all with the amps operation and could be easily straightened back out once the plexi rear panel is moved. Also, I believe the two speaker out jacks have been replaced along with a couple of the switches on the front panel and maybe the fuse holders or fuse holder caps(?). As for the tonal description of this amplifier… it has all of the classic Marshall plexi era tone… only louder… and I do mean LOUDER!! This is by far one of the loudest amps I have ever heard, and more importantly, FELT. The additional power will make your speakers move some air. If you happen to be running this through a vintage Marshall 4x12 cabinet loaded with 25watt Celestion Greenbacks, I would strongly advise that you hook up two cabinets to this head so that you do not accidentally blow any speakers… it is that powerful and has tremendous output available. Plain and simple, this is a full grown man’s amp.



Thanks for posting this. 
That's a really cool looking '68 Major.
If I had the money, I'd take it home with me.


----------



## Codyjohns




----------



## Tone Slinger

Your killing me man ! That is simply one of the best distorted Marshall tones as I've ever heard. I know EXACTLY what I'd do if I had 3 or 4K


----------



## Codyjohns

Tone Slinger said:


> Your killing me man ! That is simply one of the best distorted Marshall tones as I've ever heard. I know EXACTLY what I'd do if I had 3 or 4K



Thank you so much Andy. 

I hope one day you can purchase one of these monsters, that would be so cool.


----------



## weepman3

Question about the Major. I know that you can't use overdrives with this amp, but what about fuzz pedals or modulation/delay/reverb with them?


----------



## Codyjohns

weepman3 said:


> Question about the Major. I know that you can't use overdrives with this amp, but what about fuzz pedals or modulation/delay/reverb with them?



I think delays and reverbs are OK, I run a MXR phase 90 through my Major once in awhile.
But a fuzz pedal make me nervous, overdrives and boost pedals in most cases is not good in front of the Major.

It's just not worth the risk, I'd hate to see anymore of these amps blow up.
Many of them went to the dump because of this problem.


----------



## Codyjohns

Nathan Brown said:


> Oh to be around in those times when Majors were being thrown away! I'd haul home three or four of them and fix them up! Sell 1 and keep the other three! I'd be in Marshall heaven!



You need to get a job and start saving up your money, instead of waiting around for peoples garbage all the time.


----------



## mott555

There's a 1968 Major on ebay right now.

1968 Marshall Major Plexi Vintage Sound of Choice 200 Watts Year | eBay

I wish I was a working musician, I'd love to add this to my collection just for the history and rarity alone. And maybe use it as the clean amp in a clean/dirty bi-amp setup with my 2204.


----------



## Codyjohns

mott555 said:


> There's a 1968 Major on ebay right now.
> 
> 1968 Marshall Major Plexi Vintage Sound of Choice 200 Watts Year | eBay
> 
> I wish I was a working musician, I'd love to add this to my collection just for the history and rarity alone. And maybe use it as the clean amp in a clean/dirty bi-amp setup with my 2204.



I know, I want that amp badly.

If I had the money it would be sitting in my basement right now.

I want one more '68 Major.


----------



## Viking62

I bought mine 2 years ago from a rare guitar shop (now gone bust) in Sydney. He wanted $3000 for it I got him down to $1600 it had been modded since 1971 and now put back to original specs by Marshall amp tech Terry, so its got a few extra holes round the back. Tolex and cosmetically its in amazing condition considering its vintage, I'm guessing the previous owner/s kept in a road case. I had the polarity switch made into a half power switch. I run an OCD clean boost along with a Dunlop Univibe no probs.. Apart from its awesome power its a real tone machine!


----------



## Codyjohns

Viking62 said:


> I bought mine 2 years ago from a rare guitar shop (now gone bust) in Sydney. He wanted $3000 for it I got him down to $1600 it had been modded since 1971 and now put back to original specs by Marshall amp tech Terry, so its got a few extra holes round the back. Tolex and cosmetically its in amazing condition considering its vintage, I'm guessing the previous owner/s kept in a road case. I had the polarity switch made into a half power switch. I run an OCD clean boost along with a Dunlop Univibe no probs.. Apart from its awesome power its a real tone machine!



That's a sweet amp and it is in great cosmetic condition. 

It looks like a D in your serial number which would make it a 1972, not a 1971.

The letter C in the serial number would make it a '71.


----------



## Viking62

Michael RT said:


> That's a sweet amp and it is in great cosmetic condition.
> 
> It looks like a D in your serial number which would make it a 1972, not a 1971.
> 
> The letter C in the serial number would make it a '71.



Cheers thanks for that, shall correct.. still a TONE MACHINE!


----------



## Codyjohns

Viking62 said:


> Cheers thanks for that, shall correct.. still a TONE MACHINE!



Yip, they are Tone Machines !! 

I love them.


----------



## AlvisX

weepman3 said:


> Question about the Major. I know that you can't use overdrives with this amp, but what about fuzz pedals or modulation/delay/reverb with them?



Im pretty sure Ronson used a Tone Bender or Fuzz Face around the "Spiders" era ....It dont get any more MAJOR than Ronson !!!


----------



## Codyjohns

AlvisX said:


> Im pretty sure Ronson used a Tone Bender or Fuzz Face around the "Spiders" era ....It dont get any more MAJOR than Ronson !!!



Ronson was using the first Marshall 200 built in '67 (The Pig), not the same amp as the '68 to '74 Majors.
The '67 200 watt Marshall's also used Partridge transformers and not Dagnalls like the '68 to '74 Majors.


----------



## AlvisX

Michael RT said:


> The '67 200 watt Marshall's also used Partridge transformers and not Dagnalls like the '68 to '74 Majors.



Were those UL as well ?


----------



## Codyjohns

AlvisX said:


> Were those UL as well ?



I don't know a lot about "the pig" but from what I know it's not an ultra linear design.


----------



## Appetite4distortion

Also, the pig had active EQ as well! with only three knobs..master volume, bass, and treble.
It is surely one of the rarest marshall ever made.

Here's couple of clips of a lucky guy who owns one..very thick, raw and politically uncorrect:

[ame="http://www.youtube.com/watch?v=qHav_y8doTg"]The MARSHALL 200 aka 'The Pig' - YouTube[/ame]

[ame="http://www.youtube.com/watch?v=YUH9oEpjtfk"]The MARSHALL 200 plays "I'm Waiting For The Man" - YouTube[/ame]


----------



## Codyjohns

Appetite4distortion said:


> Also, the pig had active EQ as well! with only three knobs..master volume, bass, and treble.
> It is surely one of the rarest marshall ever made.
> 
> Here's couple of clips of a lucky guy who owns one..very thick, raw and politically uncorrect:
> 
> The MARSHALL 200 aka 'The Pig' - YouTube
> 
> The MARSHALL 200 plays "I'm Waiting For The Man" - YouTube



Thanks for posting the clips, the amp sounds awesome. 

I wish I had one.


----------



## AlvisX

Is this it ?
My eyesight is not what it used to be , but looks like there are UL taps? 

http://www.drtube.com/schematics/marshall/200w.gif


----------



## Codyjohns

AlvisX said:


> Is this it ?
> My eyesight is not what it used to be , but looks like there are UL taps?
> 
> http://www.drtube.com/schematics/marshall/200w.gif



No that's not it.

That's a schematic of my '68 Major model #1978 bass circuit, which is UL and has the passive tone controls.


----------



## AlvisX

Right, I didn't look at the front end


----------



## Appetite4distortion

There's also a world-class blues legend guitar hero who is strange to believe, but he really used Majors often in combination with other amps: Mr. Stevie Ray Vaughan!!!!

https://www.youtube.com/watch?v=wonLLnblQik&feature=related


----------



## Codyjohns

That's a cool interview. 

I remember seeing this picture of SRV awhile ago and saying "look at that Major be hide him" !!


----------



## AlvisX

So .....I thought I finally healed up enough to crawl inside the '68 PA 
Oh,what an awkward beast.......But STILL easier to work on than an ampeg ....

When I was talking to the guy on the phone (pre-purchase) I asked him what were the mods ,as advertised
He said he didn't exactly know but ,"they added some distortion" 
Im thinkin...Oh hell...gain-i-ac...can o' worms . But Im usually up for a challenge when a Marshall is concerned ...so I bit it

So I finally got that chassis out 
Power section looked pretty good ,was re-capped in '08  ,whoever re-capped it did a great,clean job
Someone put in a PPIMV as well

On to the preamp section. 
So at some point ,someone had done a cascade mod using channels 3 & 4
As I said before , I found it to be waaay too over the top ....Gain aint no good if you dont have the TONE to go with it 
They had 820ohm/330uf on one cathode (the stock cap would've a 250uf...shared) and a 2.7k /.68uf on the other. .001uf cap across the pot and a 470pf over the mixer resistor ...ewwwwwwww mosquitos
I decided to go with 2203/4 values and put a 10k resistor in place of the 820/330 combo. Pulled the cap of the pot ,left the one on the mixer for now. Using a 5751 in this slot
NOW,it sounds like a Marshall and not an 85 lb Boss pedal ...hahahahaha
Nice n fat ,good crunch ala 1976. I'll have to a/b it with the 2203 at some point 
Man i wish I had made a little clip of the _before _sound , but really .... I couldnt stand it 

The other channels I intend to use for bass. I put a 12ay7 in that slot. They have shared cathode 820ohm/250uf. I added a .001 cap across one volume pot & jump the channels just like I would do with guitar . Having that brite channel adds a little articulation ....not so it sounds like the bass player on Seinfeld ...I hate that sh*t. It still sounds like a Marshall

Hey Michael RT, you have a Bass model ,correct? Did you leave the .47uf output couplers in ?


----------



## Codyjohns

Sounds like you had to tame a beast. 

I'm on the same page as you, I like gain but it's got to be articulate sounding. 

My '68 is a bass model (1978) 

Yip, my PI couplers are the stock .47uF.

One thing I found that sounded really good in this amp was to change the slope resistor from a 56K to a 47K. 
It tighten things up and gave it some sweet sounding mids.


----------



## AlvisX

Hey Michael, when you got your back panel,did you have to give them dimensions ?
Thx


----------



## Codyjohns

AlvisX said:


> Hey Michael, when you got your back panel,did you have to give them dimensions ?
> Thx



No I didn't give them my dimensions for the back panel.
I ordered the 100w Super Lead panel from Mojo and it fit perfectly. 

I know for a fact that Mojo makes them all from scratch so you should be able to give them your dimensions, yours might be a little different because it's the two channel version. 

Mojo doesn't drill the 4 holes for the screws, so you won't need those measurements.


----------



## AlvisX

Michael RT said:


> No I didn't give them my dimensions for the back panel.
> I ordered the 100w Super Lead panel from Mojo and it fit perfectly.
> 
> I know for a fact that Mojo makes them all from scratch so you should be able to give them your dimensions, yours might be a little different because it's the two channel version.
> 
> Mojo doesn't drill the 4 holes for the screws, so you won't need those measurements.



Excellent ....for some reason I always though the Major box was taller ...... but it's just deeper . My SL panel fits fine .Thx for the info


----------



## Codyjohns

AlvisX said:


> Excellent ....for some reason I always though the Major box was taller ...... but it's just deeper . My SL panel fits fine .Thx for the info



The Major's head cab is taller to accommodate the output transformer but it's not taller by much. (about 1inch)
I think Marshall designed the back of the Major's head cab to fit the 100w panel, probably to save time and money.


----------



## Appetite4distortion

I like so much the deeper cabinet size of the major, it gives a mighty aura..
Also it fits exactly the top of a 1960A cabinet, while the 100W heads leaves spare room around. Somewhat skinny/slim in comparison
Seems a match made in heaven! 

The only thing I don't like of the major is: its weight when I have to carry it around  but it's definitely worth its monster tone.


----------



## AlvisX

Appetite4distortion said:


> I like so much the deeper cabinet size of the major, it gives a mighty aura..



That's right . There was a guy in Switzerland about 10 years ago had a Major stack ....two 4x15 cabs . I really wanted that rig for my bass rig in Europe, but just wasn't able to swing it at the time ...it was taller than I am (6'5")

I had a picture of it somewhere around here


----------



## Codyjohns

Appetite4distortion said:


> I like so much the deeper cabinet size of the major, it gives a mighty aura..
> Also it fits exactly the top of a 1960A cabinet, while the 100W heads leaves spare room around. Somewhat skinny/slim in comparison
> Seems a match made in heaven!
> 
> The only thing I don't like of the major is: its weight when I have to carry it around  but it's definitely worth its monster tone.



I have to agree with you, my 100w JMP looks tiny compared to the my Majors monster size. 
Majors just look wicked. 
They are heavy as hell but worth dragging out for a live gig because they sound so damn good.


----------



## Codyjohns

AlvisX said:


> That's right . There was a guy in Switzerland about 10 years ago had a Major stack ....two 4x15 cabs . I really wanted that rig for my bass rig in Europe, but just wasn't able to swing it at the time ...it was taller than I am (6'5")
> 
> I had a picture of it somewhere around here



I would love to have one of these monster stacks be hide me on stage, they're just so powerful. 

If you find the picture post it up.


----------



## AlvisX

Ok
Dropped a camera and broke it ,so Im using my computer . Finally got a little bit of audio of the '68 PA. Forgive if levels not very good ....new "rig"
This is the result of my DE-gain-ing the cascade mod that was in there when I got it 
I wish I had made some audio / video record of the "before" sound ,but you know how it is .....you open up an amp and get to workin on it ,you forget about doing things for documentary's sake .......
Now 2.7k / .68uf on one cathode and 10k on the other
Actually enjoying playing guitar out of it for a change . I've been obsessed with tuning the other channels for bass ,as we've been using it for my band's bass rig 

[ame="http://www.youtube.com/watch?v=VKsE-z7BQRY"]1968 Marshall Major PA & VOS Les Paul Junior - YouTube[/ame]


----------



## Codyjohns

AlvisX said:


> Ok
> Dropped a camera and broke it ,so Im using my computer . Finally got a little bit of audio of the '68 PA. Forgive if levels not very good ....new "rig"
> This is the result of my DE-gain-ing the cascade mod that was in there when I got it
> I wish I had made some audio / video record of the "before" sound ,but you know how it is .....you open up an amp and get to workin on it ,you forget about doing things for documentary's sake .......
> Now 2.7k / .68uf on one cathode and 10k on the other
> Actually enjoying playing guitar out of it for a change . I've been obsessed with tuning the other channels for bass ,as we've been using it for my band's bass rig
> 
> 1968 Marshall Major PA & VOS Les Paul Junior - YouTube



The guitar sounds awesome through it, very cool classic Marshall growl.
Love it. 
Sounds like you might want to use this as a lead guitar rig now.


----------



## AlvisX

Michael RT said:


> Sounds like you might want to use this as a lead guitar rig now.



Tempting .....but then I'd have to dig out the SVT to keep up with it


----------



## Codyjohns

AlvisX said:


> Tempting .....but then I'd have to dig out the SVT to keep up with it



Yeah, it's one helluva loud lead guitar rig.


----------



## Tone Slinger

AlvisX said:


> Ok
> Dropped a camera and broke it ,so Im using my computer . Finally got a little bit of audio of the '68 PA. Forgive if levels not very good ....new "rig"
> This is the result of my DE-gain-ing the cascade mod that was in there when I got it
> I wish I had made some audio / video record of the "before" sound ,but you know how it is .....you open up an amp and get to workin on it ,you forget about doing things for documentary's sake .......
> Now 2.7k / .68uf on one cathode and 10k on the other
> Actually enjoying playing guitar out of it for a change . I've been obsessed with tuning the other channels for bass ,as we've been using it for my band's bass rig
> 
> 1968 Marshall Major PA & VOS Les Paul Junior - YouTube




More proof of how bad assed these amps are. I'm really jonesing. The foundation tone is very similar to Michaels,though Michael has squeezed a bit more gain out of his. The PA and Bass models must have some circuit similarities huh ? I will someday have one


----------



## Appetite4distortion

AlvisX said:


> Ok
> Dropped a camera and broke it ,so Im using my computer . Finally got a little bit of audio of the '68 PA. Forgive if levels not very good ....new "rig"
> This is the result of my DE-gain-ing the cascade mod that was in there when I got it
> I wish I had made some audio / video record of the "before" sound ,but you know how it is .....you open up an amp and get to workin on it ,you forget about doing things for documentary's sake .......
> Now 2.7k / .68uf on one cathode and 10k on the other
> Actually enjoying playing guitar out of it for a change . I've been obsessed with tuning the other channels for bass ,as we've been using it for my band's bass rig
> 
> 1968 Marshall Major PA & VOS Les Paul Junior - YouTube




So thick and warm! Like it!
What's the curly cable brand? Curious


----------



## AlvisX

Well , to tell ya the truth , if I wasn't so hung up on ol' school tube bass tone , I probably woun't have such a beast . I've been using my 100 watters for bass for awhile .When I stumbled upon this behemoth, I thought the little xtra kick would make a cool bass amp 
It sounds so much better for my music than any kind of modern bass rig ('cept the SVT ,which really aint modern)
I also like having amps on the road that I can work on ...Marshalls are pretty easy if you know what you're doing . The bulk of my electronics training was actually hi powered tube radio...so....guitar amp's not a stretch

For live performance ,guitar-wise , I usually use anything from a tweeded champ to a 50w Marshall on indoor gigs , depending on the venue size ....and knowing what I can get away with . Outdoors I tend to let it rip with a hunderd watter . I try to remember Im a singer 1st so I gotta watch it, drownin myself out because of a lust for a loud screamin ass guitar amp....

Yes, the bass model major & the PA have .47uf output coupling caps.......great contributors to the thickness . My cascaded channels are more or less tuned to your regular ol' 2203/4 specs. I had a lot more space to go on the gain knob , that was actually more than I would prefer . I got a newborn livin next door so I try to be a little considerate . I would've actually liked more master and less preamp on that clip , but I beat the sh*t outa my neighbors for about 7 hrs a day when Im around . I think it was adequate to illustrate what's goin on with the amp
Man ,it's a LOUD mthafckr!

The curly cord in the clip is the cheap Radio Shack variety, my "playin around the house" cable . My actual stage cable is a Lava cable though , if you're lookn for a good curly cord


----------



## Codyjohns

AlvisX said:


> Well , to tell ya the truth , if I wasn't so hung up on ol' school tube bass tone , I probably woun't have such a beast . I've been using my 100 watters for bass for awhile .When I stumbled upon this behemoth, I thought the little xtra kick would make a cool bass amp
> It sounds so much better for my music than any kind of modern bass rig ('cept the SVT ,which really aint modern)
> I also like having amps on the road that I can work on ...Marshalls are pretty easy if you know what you're doing . The bulk of my electronics training was actually hi powered tube radio...so....guitar amp's not a stretch
> 
> For live performance ,guitar-wise , I usually use anything from a tweeded champ to a 50w Marshall on indoor gigs , depending on the venue size ....and knowing what I can get away with . Outdoors I tend to let it rip with a hunderd watter . I try to remember Im a singer 1st so I gotta watch it, drownin myself out because of a lust for a loud screamin ass guitar amp....
> 
> Yes, the bass model major & the PA have .47uf output coupling caps.......great contributors to the thickness . My cascaded channels are more or less tuned to your regular ol' 2203/4 specs. I had a lot more space to go on the gain knob , that was actually more than I would prefer . I got a newborn livin next door so I try to be a little considerate . I would've actually liked more master and less preamp on that clip , but I beat the sh*t outa my neighbors for about 7 hrs a day when Im around . I think it was adequate to illustrate what's goin on with the amp
> Man ,it's a LOUD mthafckr!
> 
> The curly cord in the clip is the cheap Radio Shack variety, my "playin around the house" cable . My actual stage cable is a Lava cable though , if you're lookn for a good curly cord



The .47uF output couplers is one of the things that really set this amp apart from the rest, the tight thickness. 

I'm really surprised how good a six string sounds threw a bass Major circuit.
What a beautiful classic tone. 
It is one loud mother but these Majors sound amazing when ya crank them up. 
The louder you turn it up and back the gain off, the better it sounds.


----------



## whamo6

I have a major 200 watt that I have owned for 25 years. The chassis has a date written on it 2-18-69. I used this amp constantly up until about 3 months ago. Looking to sell it. Should I take it to someone to get appraised? not sure what it is worth. Any advice would be greatly appreciated.


----------



## Codyjohns

whamo6 said:


> I have a major 200 watt that I have owned for 25 years. The chassis has a date written on it 2-18-69. I used this amp constantly up until about 3 months ago. Looking to sell it. Should I take it to someone to get appraised? not sure what it is worth. Any advice would be greatly appreciated.



My honest opinion is the amp head is worth between 4 to 5,000 bucks. 

Do you have pictures of the amp head you can post so I can have a good look at it ??


----------



## Tone Slinger

Michael RT said:


> My honest opinion is the amp head is worth between 4 to 5,000 bucks.
> 
> Do you have pictures of the amp head you can post so I can have a good look at it ??



C'mon Michael,dont tell him that , how are all of us 'Majorly want a MAJOR' guy's gonna be able to afford one. Shoulda said, "Oh, maybe a Grand to a grand and a half .

Ha, Ha, just kidding, those things are EXPENSIVE cause they are both RARE and sound AMAZING


----------



## whamo6

I will take some pics thursday. I will say this. it is road worn and I do not have the original knobs or marshall emblem. Bought it from a friend that owned a music store in the early 90's. I will post some pics. Thanks.


----------



## Codyjohns

Tone Slinger said:


> C'mon Michael,dont tell him that , how are all of us 'Majorly want a MAJOR' guy's gonna be able to afford one. Shoulda said, "Oh, maybe a Grand to a grand and a half .
> 
> Ha, Ha, just kidding, those things are EXPENSIVE cause they are both RARE and sound AMAZING



I really want you to get Major my friend, if and when you do get one we can clone my '68 circuit. 



whamo6 said:


> I will take some pics thursday. I will say this. it is road worn and I do not have the original knobs or marshall emblem. Bought it from a friend that owned a music store in the early 90's. I will post some pics. Thanks.



Yeah, if it's beat up badly it will affect the price.
Does it have the original transformers in it ?? 
Pictures will help determine its value better.


----------



## AlvisX

Another shot o' the Major as I had a bad audio cable on that last clip 

[ame=http://www.youtube.com/watch?v=y2pQMO8PnwM]Marshall Major PA '68 Alvin Youngblood Hart - YouTube[/ame]


----------



## Codyjohns

Sounds awesome Alvin !! 

You did a great job on that '68. 

What speakers are you using in the clip ??


----------



## AlvisX

Cheers
Those are WGS ET-65's


----------



## Codyjohns

AlvisX said:


> Cheers
> Those are WGS ET-65's



I use to have a Marshall 4x12 with Celestion G12-65's in it.
I should have kept the cab but I sold it awhile ago. 
I always liked 65's, nice sounding speakers.


----------



## Codyjohns




----------



## Codyjohns

Hey guys, just wanted to share this great info with everyone here. 

John "Dawk" Stillwell (Richie Blackmore's old amp tech) shared this info about the Major with me just recently so I thought I would pass it along.
Nobody knows this amp better then Dawk,
And I Quote :

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

DAWK SAYS:

OK,,, HERE THE RESEARCH ON THE ''DAGNALL'' OUTPUT TRANSFORMER I DID...

SO WHY DID ''MARSHALL'' MAKE THE MAJOR'' ?? 

IT WAS REALLY ''MARSHALL'S'' ANSWER TO THERE COMPETITION ( THE SUNN 2000/S )...


THE ''SUNN'' USED ( DYNACO ) TRANSFORMERS...

THE DYNACO COMPANY'S MADE VERY HIGH QUALITY TRANSFORMERS THAT ( DIDN'T NOT BLOW UP )...

ON THE OTHER HAND THE ''MARSHALL / DAGNALL'' TRANSFORMER WERE ((( CRAP )))...


THE PROBLEM IS: ''DAGNALL'' WOUND THERE WINDING ON TOP OF WINDINGS AND THAT WHAT CAUSING,,,

THE ( SMOKE ON THE WATER ) EFFECT...


CAUSES: NOW INSIDE THE ''DAGNALL'' TRANSFORMER THERE IS ONLY VERY THIN LAYER OF INSULATION ON THE WIRES... ( WIRE ON TOP OF WIRE )

WHERE IN THE ''DYNACO'' HAS A LAYER OF MYLAR INSULATION WOUND BETWEEN EACH LAYER OF WINDINGS...

THIS KEEPS THE HIGH VOLTAGE FROM ''ARCING OVER'' FROM LAYER TO LAYER...


ALSO THE POWER AMP SECTION WAS NOT DESIGNED BY ''MARSHALL'' BUT,,, BY ( GEC ) THAT MADE THE REAL ( KT-88'S )...


TO GET THE RATING OF ''200 WATTS '' ( GEC ) BOOSTED THE ( B+ ) TO OVER ( 625 ) VOLTS,,,

AND THAT'S WHAT CAUSES THE ( S, O, T, W ) EFFECT...


YEAH,,, SO NOW,,, THE ( KT-88'S ) ARE BEING PUSHED TO WHAT ''I'' CALL,,, ''WAR EMERGENCY POWER''...

RATINGS: THE ( KT-88 ) ((( MAXIUM RATING))) IS ( 450 VOLT OF B+ ) WITH THE PLATE DISSIPATION OF 35 WATTS...

MORE LATER...........

YOURS,,, JOHN ''DAWK'' STILLWELL...


----------



## dslman

Wow, I hope the reissue 2203 Dagnall is a better design.


----------



## Codyjohns

dslman said:


> Wow, I hope the reissue 2203 Dagnall is a better design.



Dawk is specifically talking about the 200w OT that Dagnall made for Marshall many years ago.

The 100w and 50w OT's never experienced these types of problems because the B+ was much lower in most cases, including your reissue.


----------



## dslman

Michael RT said:


> Dawk is specifically talking about the 200w OT that Dagnall made for Marshall many years ago.
> 
> The 100w and 50w OT's never experienced these types of problems because the B+ was much lower in these amps, including your reissue.


I see , Thanks Michael, The current ones in the 2203x are huge , and heavy, very lopsided as far as weight distribution. It sounds great though. 
Sorry for the butt in .:cool2:


----------



## usednabused

majors are just insane...
kinda scary volume if you ask me...
kinda... drunk with power volume!


----------



## Codyjohns

usednabused said:


> majors are just insane...
> kinda scary volume if you ask me...
> kinda... drunk with power volume!



Definitely not an amplifier for the faint of heart.

They have been known to scare the shit out of people from time to time.


----------



## usednabused

again...VULGAR DISPLAY OF VOLUME!!!!


----------



## Codyjohns

You can never have too many youtube sound clips in one thread.


----------



## Codyjohns

.


----------



## Codyjohns




----------



## Codyjohns

.


----------



## Codyjohns




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## mAx___

Deleted post.


----------



## munger77

Michael RT; your amp sounds awesome;

I still have my '68 or early '69 Major (1967 model) in my basement with a layer of dust on the tolex - I'd like to do the exact same modifications and see how it compares to yours. Any help would be much appreciated regarding the correct mods.


----------



## clusterstudios

Found these on the web. Major mods on the Major. Anybody have any idea what these mods are? Looks like an extra preamp tube and MV plus some extra tone shaping Mods.


----------



## clusterstudios

more gut shots...


----------



## mAx___

What a mess!


----------



## Codyjohns

clusterstudios said:


> Found these on the web. Major mods on the Major. Anybody have any idea what these mods are? Looks like an extra preamp tube and MV plus some extra tone shaping Mods.



I have no clue my friend.
Kinda messy if you ask me.


----------



## Codyjohns

.


----------



## Codyjohns

.


----------



## strato2009

Those amps even look intimidating, pure power.

Michael, did you use any pedals or attenuator in the clips?


----------



## Codyjohns

strato2009 said:


> Those amps even look intimidating, pure power.
> 
> Michael, did you use any pedals or attenuator in the clips?



No Sir, no pedals or attenuators, plugged straight into the amp head. (plug & play)


----------



## strato2009

Do you wear ear protection and where do you keep the volume knob?

Very nice tone.


----------



## pleximaster




----------



## Codyjohns

strato2009 said:


> Do you wear ear protection and where do you keep the volume knob?
> 
> Very nice tone.



Thank you!!
I can get that cranked-up sound at low volumes because of the PPIMV I have installed in my beast.


----------



## Codyjohns

pleximaster said:


>



Those look like the Marshall 15 inch Celestion cabs, man I wish I owned a set of those cabs, prefect match for my Major.


----------



## pleximaster

Yes they are 4x15 imported to Sweden together with the consecutive serial numbers. Not mine but a good friend of mine just got this setup!

plexi


----------



## strato2009

Michael RT said:


> Thank you!!
> I can get that cranked-up sound at low volumes because of the PPIMV I have installed in my beast.



How high do you dial the MV usually?


----------



## Codyjohns

strato2009 said:


> How high do you dial the MV usually?



I mostly have the master set around 9 o'clock, I'm very careful not to blow my speakers up. 
I already lost one greenback and I don't want to lose another.


----------



## Codyjohns

It is with great sadness that I announce the passing of John "Dawk" Stillwell.
Thank you for giving us the chance to understand the technology behind Ritchie Blackmore's sound. 

All my prayers to the family, RIP John.


----------



## AlvisX

I heard that too, the Master of The Major ...RIP

http://www.thehighwaystar.com/thsblog/2015/12/23/john-dawk-stilwell-r-i-p/


----------



## Codyjohns

AlvisX said:


> I heard that too, the Master of The Major ...RIP
> 
> http://www.thehighwaystar.com/thsblog/2015/12/23/john-dawk-stilwell-r-i-p/



Yeah, it's so sad.
I learned so much about the Major and mods from John as he was so kind and helpful towards me over the years.


----------



## Codyjohns

Gear Used:
Ibanez Jem with Seymour Duncan SH-4 bridge.
1968 Marshall Major Plexi 200 watt.
Marshall Full Stack with Celestion G12M greenbacks.


----------



## strato2009

I almost had a heart attack when you started playing after sitting so quietly in the start


----------



## Codyjohns

strato2009 said:


> I almost had a heart attack when you started playing after sitting so quietly in the start



I know, I should have put a viewer warning out on this one.


----------



## Codyjohns

Here's the amp that started it all and an awesome clip of it.


----------



## Codyjohns

I think I'll sneak this in here.


----------



## Codyjohns

.


----------



## Codyjohns




----------



## myersbw

Hi Michael,

A first post for me here. I've recently had a local player bring me what seems to be a 1968 Major. It's in the ridiculous clean mode for now. Some breakup and some mods (MV, but haven't traced to where yet.) Note the Chicago PT there!  The chassis just barely slides into the box. Anyhow, I'm trying to glean your thread for notes to cascade the stages, etc. My background is EET and I'm into a couple years of tube amp build/repair/mod now (retiring the day job in 4 years so starting my second part-time career in advance!)

Do you happen to have a pdf or word doc or (?) that would give a bucket list of all the mods you've made for the Major? I'm seeing everything from PPIMV to OneWire mod to mustard caps, etc. Would be nice to have a list to check off as I step through it. 

Also, I'm not seeing the 39ohm power resistors in your chassis? Where they removed or just never existed in your version? I'm hoping to either upload some files or post photos of this chassis as it is. I was quite amazed with the transformer. It's currently set to run 6550's and is using the lower 370-0-370 tap on the PT.

if someone could point me to the process of uploading files or sharing photos it would be so much appreciated...I'm just not finding it anywhere. And, can't seem to find how I can populate the media gallery with photos either (or make an album). Thanks!!!

Brad


----------



## Codyjohns

myersbw said:


> Hi Michael,
> 
> A first post for me here. I've recently had a local player bring me what seems to be a 1968 Major. It's in the ridiculous clean mode for now. Some breakup and some mods (MV, but haven't traced to where yet.) Note the Chicago PT there!  The chassis just barely slides into the box. Anyhow, I'm trying to glean your thread for notes to cascade the stages, etc. My background is EET and I'm into a couple years of tube amp build/repair/mod now (retiring the day job in 4 years so starting my second part-time career in advance!)
> 
> Do you happen to have a pdf or word doc or (?) that would give a bucket list of all the mods you've made for the Major? I'm seeing everything from PPIMV to OneWire mod to mustard caps, etc. Would be nice to have a list to check off as I step through it.
> 
> Also, I'm not seeing the 39ohm power resistors in your chassis? Where they removed or just never existed in your version? I'm hoping to either upload some files or post photos of this chassis as it is. I was quite amazed with the transformer. It's currently set to run 6550's and is using the lower 370-0-370 tap on the PT.
> 
> if someone could point me to the process of uploading files or sharing photos it would be so much appreciated...I'm just not finding it anywhere. And, can't seem to find how I can populate the media gallery with photos either (or make an album). Thanks!!!
> 
> Brad



Well first off,
Welcome to the forum Brad.
I'm sorry but I do not have any schematics on my Major modifications and I don't really plan on sharing my all secrets with everyone who asks me. I will do a Major with my mods but I need to have it in my hand first because so much can easily go wrong with these amps and I don't want to be responsible for very costly damage.
My screen grid resistors are there, you just have to look a little closer.
As far as sharing picture I just use photobucket and upload my picture there than copy & past the share links and past them here on the forum. Works great for.
However, I would like to see some pictures of the Major you're working on, I'm sure I can be of some help to you.
Actually this video I made might be helpful to you, but this is about as far as I've gone with things.


----------



## myersbw

Michael RT said:


> Well first off,
> Welcome to the forum Brad.
> I'm sorry but I do not have any schematics on my Major modifications and I don't really plan on sharing my all secrets with everyone who asks me. I will do a Major with my mods but I need to have it in my hand first because so much can easily go wrong with these amps and I don't want to be responsible for very costly damage.
> My screen grid resistors are there, you just have to look a little closer.
> As far as sharing picture I just use photobucket and upload my picture there than copy & past the share links and past them here on the forum. Works great for.
> However, I would like to see some pictures of the Major you're working on, I'm sure I can be of some help to you.
> Actually this video I made might be helpful to you, but this is about as far as I've gone with things.





Thanks for the response, Michael. Ha, "I publicly release you from any damage I might inflict on this amp or myself".  I wasn't after a schematic...just a rundown of changes. I certainly won't move this up North given the shipping costs on the beast. But, I'll spend the time blowing up the images assuming you're portraying the amp circuit in final state...?  In any case, thanks much for your time spent.

JUST as I was uploading to photo bucket, they took a maintenance dive. Sooooo, here's some Google Photos of the amp to browse a bit. Let me know what you think of this one, if you don't mind. 

https://goo.gl/photos/aEcD2nKUjBPBRaD58


----------



## Codyjohns

myersbw said:


> Thanks for the response, Michael. Ha, "I publicly release you from any damage I might inflict on this amp or myself".  I wasn't after a schematic...just a rundown of changes. I certainly won't move this up North given the shipping costs on the beast. But, I'll spend the time blowing up the images assuming you're portraying the amp circuit in final state...?  In any case, thanks much for your time spent.
> 
> JUST as I was uploading to photo bucket, they took a maintenance dive. Sooooo, here's some Google Photos of the amp to browse a bit. Let me know what you think of this one, if you don't mind.
> 
> https://goo.gl/photos/aEcD2nKUjBPBRaD58



It look like a early 70's Major model# 1978 bass circuit. It look all stock other than the PPIMV and PT. Most of the PT's blew in these amps because of the UL design and also people weren't using them the way they were intended to be.
I'm going to direct you to this thread with tons of great info on the Major and mods, definitely ask your questions there and they will help you out. 
http://el34world.com/Forum/index.php?topic=17548.0


----------



## myersbw

Maybe a bass circuit, but built/tested in 1968 (see link), Michael. Thanks for the head's up on the EL34 site...been a while since I've been there. BTW, did you yank the 39 ohm resistors out of yours or did they not exist? 

https://goo.gl/photos/FGCqsGitzouc5f8LA

Thanks,
Brad


----------



## iron broadsword

Every time you turn this amp on, polar bears weep.


----------



## coldengray

Brad - that's a 70s board.


----------



## Codyjohns

iron broadsword said:


> Every time you turn this amp on, polar bears weep.



It would kinda sound like this.


----------



## myersbw

coldengray said:


> Brad - that's a 70s board.




Well, the chassis tag says tested in 1968. So, since the transformer isn't original, what do you think? Might someone have actually replaced the board? A bit extreme, but not if a fire ensued?? lol Unless Marty McFly was involved. So the mystery continues...

I suppose the way some blow up, I can see fast trade-ins leading to a couple in some shop where a would-be tech cobbles one working amp from two...?


----------



## Codyjohns

coldengray said:


> Brad - that's a 70s board.



You are 100% right.
It is not a 1968 Marshall Major Plexi.
It's a early 70's metal face Marshall Major.
I don't even think they used those service tags in '68 on the Majors. 
But regardless even the circuit changes and parts tell me it's definitely an early 70's Major.

What letter is in the serial number??


----------



## myersbw

SN is A0863C


----------



## Codyjohns

myersbw said:


> SN is A0863C



There should be only one letter in the SN and not two so it's probably C the last letter which is 1971.

Yup, it's definitely a 1971 Major.


----------



## myersbw

Technically, the 'A' is part of the "serial number"...just a designator it's a Major. https://goo.gl/photos/X5MucnNDGmVSkjgM7

Now the paper tag get's interesting, eh? Were those placed on the chassis? Or, do you think someone doctored that a bit? Hmmm


----------



## Codyjohns

myersbw said:


> Technically, the 'A' is part of the "serial number"...just a designator it's a Major. https://goo.gl/photos/X5MucnNDGmVSkjgM7
> 
> Now the paper tag get's interesting, eh? Were those placed on the chassis? Or, do you think someone doctored that a bit? Hmmm



The A stands for 200w model and the stamped C stands for year 1971.
Yes, the tags were placed on the chassis and I would say that someone must have doctored it a bit.


----------



## myersbw

Michael, I suppose the other possibility is a reworked 68 chassis. ? I can also see someone cobbling two together at some point. From the looks of the paper tag, it doesn't look like a fake regarding the tag. Not really important I suppose.


----------



## Codyjohns

In your power stage the 56mA of platecurrent will run through the cathode ( + a few mA's for the screen )

This gives you around 2,184v across the "39 ohm" cathode resistors ( 39ohm x 0.056A) = V


----------



## myersbw

Not quite an 1/8 watt, eh? You using a 1/4 or a 1/2 watt for those?


----------



## Codyjohns

myersbw said:


> Not quite an 1/8 watt, eh? You using a 1/4 or a 1/2 watt for those?



Yeah, I don't think so. 

It's my understanding the early model Major's don't use this configuration but I am very familiar with it's use in the later models like yours.


----------



## myersbw

Well, one things for certain...glad I'm just modding it and don't own it. At 57, I'm a bit tired of amps that make me feel I'm carrying a corpse! :O I do have a hybrid project I'm about to start...an 18watter TMB married to a JTM45 output stage for a bit more oomph. I incorporated channel switching into my last 18w build (used Mojo's relay kit, fine if you use high grade shielded wire). I may do the same with this mod...not for certain yet.


----------



## Codyjohns

myersbw said:


> Michael, I suppose the other possibility is a reworked 68 chassis. ? I can also see someone cobbling two together at some point. From the looks of the paper tag, it doesn't look like a fake regarding the tag. Not really important I suppose.



There is nothing in this amp that says '68 Major Plexi to me other than the tag which is a false representation of this Major. The chassis in '68 were all plexi front and back panels and not metal like on your '71. So that rules out the possible of a reworked '68 chassis.
Anyways, I wish you the best of luck with your '71 Major and your modifications, hopefully it will behave for you over the years like my '68 has for me.

Best sounding amp I've ever owned and played threw.


----------



## myersbw

I don't know, Michael. I think it's a moot point to belittle the dates unless proven otherwise. My take is that it's a combination of perhaps older and newer (for the day) and for reasons neither you or I know. Removing that tag would be inappropriate as much seems valid including the glue/varnish/lacquer used to adhere it. The other perspective is...the amps have a history of meltdown, so I doubt it uncommon to see the broken ones collected and abandoned in pursuit of more practical stable builds.

There's no question about the faceplates and dates, but that could also suggest that the "cheap plastic" ones were abandoned for some "cool metal ones" during the resurrect process. And, the rebuilt is absolutely supported by the transformer changes, etc. Heck, if I were a 20-something kid with cash in the early-to-mid 70's...guess which faceplate I'D want! Not the crappy plastic one.  Another thought...if this monster steel chassis took a major fall, my guess is the chassis would suffer enough that it warrants scarfing up a chassis out of an old dead one sitting in a corner. Just sayin'

I think its best to leave it all as it is. It shows a diverse troubled history that's plagued this amp series. And, the bottom line is, this amp...your amp...every modded amp...falls into the category of "misrepresenting" the amp in it's true original state (which almost nobody playing wants).

It's not my amp...I'm simply hired to mod it for their practical use. So, I'm spending time gleaning pages for changes people have liked to do in making this a practical and safe amp...nothing more. But, I do find it's jaded and controversial design past a bit fascinating.

Thanks for all the input you folks have shared regarding it. One day I hope someone will bucket-list the changes for many to see. It's not like taking this info to the grave ever serves any purpose except for the lack of one being a willing teacher. As for some folks trademarked mods? I typically have a chuckled at that when I see the old Fender Bassman circuit in an early Marshall JTM. 

Keep on modding and teaching folks....it's the only way the classic tube monsters will survive. 

Cheers!
Brad


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## Codyjohns




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## coldengray

The odds of someone changing the date on the tag (to make it seem more valuable) are much, much higher than someone changing every part to 70s pieces. I would bet $1000 every pot code is 70s. My 2 cents.


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## myersbw

Could be!  But, if I spend much more time pursuing it...I lose money.  The nice part of this is the danger zone has dropped. B+ with this transformer puts it at 512V, 6550's are in it now...dropping down to 250V right at the V1 plates. The PPIMV just lacks the pair of 220K resistors...easy enough to insert. I'll do the OWM to it...may even setup a channel switcher for it. Replace the caps, insert 1ohm bias resistors, tweak a little and done. Will check the pot dates for kicks when time. Actually may end up replacing a few anyways. Somewhere along the way there was a nasty little fire inside it...no one did much for cleaning it up. Here we go!


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## Codyjohns

.


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## Codyjohns




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## myersbw

Hi Folks!

Well, after a parts order, I finally got the OWM mod (and then some) done on this '71 Major. I did away with the Ch1 jacks (sort of) and left Ch2's input jacks. If you visit my DropBox link below, you can see the bucket list and hear a sample. (Mind you, ignore the haphazard playing...and the recording device was nothing more than my iPhone about 2' from the speaker. But, you can hear the difference).

https://www.dropbox.com/sh/gkfmktq795xjdei/AABbRhLxIV3oiQrKnzWuSUr4a?dl=0

Here's a summary of what I did...

- Used the Major schematic with OWM/PPIMV floating around the net (in the link)
- I did drop the 250uF cap down to 50uF (V1 cathode circuit)
- This pcb had a shared 820/250uF cath circuit on V1, so I added a 2.2K/.68uF cath for V1b
- Used a TPDT switch and the 3rd pole was used to switch on an LED indicator when the cascaded stage is engaged. The LED was mounted into one of the original 1/4 jacks for a bit of a nostalgic touch.
- used other PT taps and now the amp B+ is at a preferable 550V with a nice safety margin for the caps and it's loaded with 6550's

- Adding the indicator led - this was fairly easy. If you zoom in on the circuit board shot, to the right of the V1 cath circuits you'll just spot two diodes mounted right into two existing board holes vertically & secured by caulk (they'll be fine with just 6mA going through them). I did a half-wave rectifier and bridged a 330uF, 16V cap across the diodes. The twisted white/green wiring wraps around to the re-used jack now hosting the LED in it's interior. The diodes are dropping right down into V1's 6.3vac heater and the rectified/slightly filtered to the LED is 7VDC measured (after diodes) with an 820ohm resistor in series with the LED.

At first I considered some "noise insurance" given the switch, but since this was a mod I didn't want to spend the extra time dressing up shielded wiring if I needed to change it. So, I used the 22 gauge on hand and have no hum (despite the close proximity of the LED power circuit and modest filtering).

Since you can't see it, the sound file reflects a PRS Santana SE with Mojotone Levelhead pickups straight into the amp's hi input.

The switching is pop-less. Simply set the clean channel to taste, flip the switch and adjust the gain ch volume to suit. The owner picks it up tomorrow and I'm thoroughly sold on the circuit enough to incorporate it into a custom 5881 build I'm doing next. Yeehaw! Thanks for all your input here folks!!!

-Brad


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## Codyjohns

Looks good Brad, nice work.

It looks like you got a lot of good ideas from the Hoffman thread I shared.


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## myersbw

Michael RT said:


> Looks good Brad, nice work.
> 
> It looks like you got a lot of good ideas from the Hoffman thread I shared.



Thanks, Michael! Not sure if I saw that particular thread? But, I gleaned a lot. The re-write of the Major schematic (with mods) gave me a tabloid-sized print for sketching out changes I wanted to make. Then, I had to document some mods someone already did make. I didn't change the slope resistor for this one...once the preamp mods were made (and, by golly, the switch/mod/LED lamp actually worked the 1st time! ...rare) I just stopped. This one received an entire cap job at the same time.

I did catch your comment on turning the polarity switch into a toggle in/out. In reality, when I decided to do the switch, it just seemed logical to park the switch in one of the unused input jacks...parks it close to the preamp and no shielded cable was needed for any of it. Made it pretty quick and simple. Parking the indicator LED right next to it was a no-brainer. But, I will say...it was really nice how "just a little electrical tape" wrapped on the back part of the LED enabled it to snug in tightly into one of the original input jacks. 

By the time I scoped out the "original" circuit, I found so many changes that it no longer had much "vintage value" in retaining the circuit. I have to agree with y'all in here...it's a smokin' preamp when done this way!

Thanks again!


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## Codyjohns

So when are we going to hear this bad boy??


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## myersbw

Michael RT said:


> So when are we going to hear this bad boy??



Try that DropBox link again. An audio file should be there.  An m4a at the bottom. Let me know if you can't play it back.


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## myersbw

...just in case anyone can't playback an m4a. Nothing edited about this file, sorry. It was originally meant to send to the client.


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## Codyjohns

myersbw said:


> Try that DropBox link again. An audio file should be there.  An m4a at the bottom. Let me know if you can't play it back.


OK, I heard it and l like it but, you need to tighten up the bottom-end a little bit.
Other than that, it sounds really good.


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## myersbw

I know what you're hearing. It's much better "in person" vs. the iPhone recording. But, for sure...I didn't play with the slope resistor. The guy loves it as-is...else I'd tinker more. I'll certainly play a bit more with it on my personal build. dual 5881 version I'm planning.


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## Codyjohns

myersbw said:


> I know what you're hearing. It's much better "in person" vs. the iPhone recording. But, for sure...I didn't play with the slope resistor. The guy loves it as-is...else I'd tinker more. I'll certainly play a bit more with it on my personal build. dual 5881 version I'm planning.



Well good job my friend, I'm really glad it all worked out for everyone. 
Thank you for posting the clip, that was really cool.


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## Codyjohns

.


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## Valvelust

[QUOTE="Michael RT

It is with great sadness that I announce the passing of John "Dawk" Stillwell.
Thank you for giving us the chance to understand the technology behind Ritchie Blackmore's sound. 

All my prayers to the family, RIP John.

I just learned of his passing being out of the loop with my own medical issues
..... ditto the statement above.
I was fortunate to have had the opportunity to learn a lot from his input and his modifications he did so well with.

RIP


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## Codyjohns

Yeah I know, I'm still bummed out about his death. 
It is a tremendous loss.


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## Codyjohns




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## Filipe Soares

Greetings my marshall maniac friends!

My name is Filipe, I'm from brazil and I'm currently living in mexico city. When I've moved from brazil to mexico I've brought my major with me. 

This amp is not working for a while right now, I'm looking for a technician to bring it to life again but I'd like to improve the amp to modern KT88 and somehow avoid the whole burning thing in my life. 

Since Dawk passed away his material is not available in his former website. does anyone have it??? could you please share it with me?

Thank you all


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## paul-e-mann

Filipe Soares said:


> Greetings my marshall maniac friends!
> 
> My name is Filipe, I'm from brazil and I'm currently living in mexico city. When I've moved from brazil to mexico I've brought my major with me.
> 
> This amp is not working for a while right now, I'm looking for a technician to bring it to life again but I'd like to improve the amp to modern KT88 and somehow avoid the whole burning thing in my life.
> 
> Since Dawk passed away his material is not available in his former website. does anyone have it??? could you please share it with me?
> 
> Thank you all


Hows it going bud, I think you gotta find an amp tech in Mexico City, its a big city theres gotta be one around. Good luck to you and welcome to the forum. Let us know how you make out.


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## Filipe Soares

pedecamp said:


> Hows it going bud, I think you gotta find an amp tech in Mexico City, its a big city theres gotta be one around. Good luck to you and welcome to the forum. Let us know how you make out.



that´s the ideia. A friend suggested me his tech, it seems to be ok. but I´m an enginer, project manager, so I hate leaving my scope loose. I´d like to get to the tech, have a few words to see if he has experience with major, and in any case deliver the dawk material and say ¨I want you to take this in consideration while revamping my amp, also I´d like to mod A, B and C¨.

My experience is when you leave people too free to be creative you´ll be fucked.


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## Mitchell Pearrow

Filipe Soares said:


> Greetings my marshall maniac friends!
> 
> My name is Filipe, I'm from brazil and I'm currently living in mexico city. When I've moved from brazil to mexico I've brought my major with me.
> 
> This amp is not working for a while right now, I'm looking for a technician to bring it to life again but I'd like to improve the amp to modern KT88 and somehow avoid the whole burning thing in my life.
> 
> Since Dawk passed away his material is not available in his former website. does anyone have it??? could you please share it with me?
> 
> Thank you all


Welcome to the forum new brother! Cheers Mitch


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## Filipe Soares

Hi guys, does anyone know the capacitor values for the major?


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## Codyjohns

Filipe Soares said:


> Hi guys, does anyone know the capacitor values for the major?



Which model number Marshall Major are you referring to?


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## Codyjohns




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