# For more GAIN, The one wire mod.......



## superleadfixer

Ok I received a few PM asking to explain how to do it, here is the basic procedure for making that modification to your amp.

It will put you pre amp section in cascade (series) to add gain....

Gain factor will be multiplied when in series instead of adding itseft in parallel (as it is normaly know, stock)...

This is for Super Lead type amp but you can do it on similar amp also... If you want to maximise this mod do a swap of caps before you begin.....The VOLUME II channel should use the .0022uF for coupling cap and the VOLUME I bright channel should use a .022uF coupling cap...also you should use the tone stack withthe 250pF on the treble with 56K slope resistor...also use .1uF for the PI caps.... 

Go to the VOLUME II pot....unsolder the wire in the center terminal of the pot wiper...then solder this wire to GROUND, you can just solder it to the next pin on the same pot that is grounded... 

the mod itseft:*Take a 1 MEG resisitor and solder it to the center wiper.... then take the other end of the 1Meg resistor and solder it to the junction of the 68K input resistors of CHANNEL 1 .........ie you solder it where the two 68K resistors are joined together for channel 1 ... Now yo are done.... now plug guitar into channel II then turn the Channel I and Channel II volume to 10 then keep the MAster Volume to control the volume.... You should now have a good amount of gain and crunch.... Now to add extra gain and crunch you will need a 1/4 male jack only with no cable attached to it.....take this plug and stick it into channel 1 jack and you will now get even more gain..... *

_*For those wanting to try this mod it is imperative to have a Master Volume with your amp, if not it will work but won't sound very good, The MV will limit and control it, etc, Post Phase inverter master volume will do it perfect.....!!! *_

For those not familiar with amp work don't try this unless you know a little what you are doing, *VERY HIGH VOLTAGE HERE, YOU MUST KNOW HOW TO DISCHARGE FILTER CAPS BEFORE PLAYING UNDER THE CHASSIS....*

Have fun, will try to get a pic for that with the explanation, a little later!!

here's the pic, click on it:


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## Guv'nor

Thanks a lot for the detailed info.

You rock!!!!


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## ROBWAGNER1231

Hey Superleadfixer Do You Have Any Mods For Marshall Valvestate 100h Or Vs100h? Thanks


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## rockgod212

hi,
will this mod work with a 1959 circuit 100 watt plexi with a (bainzy mod)switchable extra tube added for gain? it is a metro amp that i built.


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## Wilder Amplification

rockgod212 said:


> hi,
> will this mod work with a 1959 circuit 100 watt plexi with a (bainzy mod)switchable extra tube added for gain? it is a metro amp that i built.



There'd be no point. That mod is for Super Lead Plexis with the stock valve count. Yours has the extra valve stage in it already cascaded.


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## theamericanpsycho

Will this work on a 1978 Marshall JMP 2204 MV? If not, what mod would be the closest to achieving this type of sound and gain increase?


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## shooto

theamericanpsycho said:


> Will this work on a 1978 Marshall JMP 2204 MV? If not, what mod would be the closest to achieving this type of sound and gain increase?


 
^ just saw this...would it work for a 78 JMP 2204?

thanks!


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## jblguy




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## Australian

robwagner1231 said:


> hey superleadfixer do you have any mods for marshall valvestate 100h or vs100h? Thanks



lol


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## brp

Well it's a 6 year old thread, OP last activity was 5 years ago, so you may not get an answer.


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## Australian

brp said:


> Well it's a 6 year old thread, OP last activity was 5 years ago, so you may not get an answer.



Then I'm safe from confrontation. 
I'm pissed off that it doesnt let you do capitals when you increase the size of the text. Why is that? _LOL_ looks so much better in capitals .


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## brp

Was talking to jblguy but I see he edited his post.
Ya, the no caps filter is annoying sometimes, when it interferes with comedic effect.


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## Australian

OIC. Necroposters cause so much confusion.


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## Australian

Hey cool. Jon Wilders back... oh oh... its a 2010 post. False alarm guys. Back to your amp kit making.


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## RickyLee

That one wire mod is quite cool. I am wondering if there is a way to do that to a 1987/1959 type amp, but make it switchable? Anyone tried that? In fact, is that not what the Randy Rhoads model Marshall does - switch between that one wire mod and a stock 1959 circuit?





theamericanpsycho said:


> Will this work on a 1978 Marshall JMP 2204 MV? If not, what mod would be the closest to achieving this type of sound and gain increase?



And for anyone wondering about the question posted above about doing this mod to a '78 JMP 2204, that amp is already set up with cascaded gain stages.


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## Ken

I've heard of the "one wire mod" and have always been curious to try it. 

But I suppose I'll have to buy a Super Lead first though, right? 

Ken


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## Papus

I've had the equivalent of the one wire mod done on my 2061x.
In other words, turned V1a/V1b into a cascading circuit.
It kicks ass.
I highly recommend it for any Plexi-based amp.


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## Csquare4

RickyLee said:


> That one wire mod is quite cool. I am wondering if there is a way to do that to a 1987/1959 type amp, but make it switchable? Anyone tried that? In fact, is that not what the Randy Rhoads model Marshall does - switch between that one wire mod and a stock 1959 circuit?
> 
> 
> 
> 
> 
> And for anyone wondering about the question posted above about doing this mod to a '78 JMP 2204, that amp is already set up with cascaded gain stages.



Ricky,

I have one of my Traynor YBA-1's that is converted to a 1959 circuit with the "one-wire" mod fully switchable. I used a Push/Pull DPDT pot on Channel 1 for the switching. Essentially, you plug into Channel 2 and pull the Channel 1 volume pot which then becomes a Gain control. The Channel 2 is then more of a Pre-amp Volume. Also, the Channel 2 is a SPDT push/pull with a bright capacitor on one side. I can get some wicked crunch out of this amp. If both the Gain and Channel 2 are cranked I get some unwieldy feedback, so once you get beyond about 2'oclock on both you are into uncharted territory, lol. Use it judiciously! By that point we are in ear bleed mode.

Here is a photo of the one wire mod and bright switches.








I also installed a Power Scaler circuit, which I was turned onto by a friend in Europe who designed it. It includes a 1/2 power switch for the power tubes/bias, then a Scaler pot for going from 1/2 power to zero volume. I tweaked it to fit, installed dual-bias supply and what KOC calls an "Improved Dual Bootstrap" Master Volume. 

Here is a photo of the Power scaling/dual bias circuit, pre-wired. I designed the circuit board and etched it myself.






This thing is now sexy as hell. 

Craig


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## GIBSON67

I plan on adding a MV and then this mod, but a cap job is in order, first.


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## dreyn77

I've looked inside the 1959rr and there is 2 resistors missing and 2 capacitors missing and there are wires missing and lots of wires going to one post. so more changes than you might think!


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## dreyn77

Was the cascade on the old 50 watt jmps repeated on other amps?


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## Les Moore

RickyLee said:


> That one wire mod is quite cool. I am wondering if there is a way to do that to a 1987/1959 type amp, but make it switchable? Anyone tried that? In fact, is that not what the Randy Rhoads model Marshall does - switch between that one wire mod and a stock 1959 circuit?
> 
> 
> 
> 
> 
> And for anyone wondering about the question posted above about doing this mod to a '78 JMP 2204, that amp is already set up with cascaded gain stages.


 
Is this what you mean?
http://www.marshallforum.com/workbench/36317-what-hell-kind-mod-do-i-have.html


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