Mod JVM or sell it?

[ShatteredVitreous]

Yeah, but the tone is still always in the next thing you don't have, right.

True, but he is not chasing the next tone, he is chasing the JCM800 and if I am not wrong, the best amp to do that is a JCM800.

The tone chasing will never stop, I agree, but if you want 20 “close enough” tones, go digital.

 

[saxon68]

This guy modded his JVM and its awesome in my opinion.

He’s a helluva player also that don’t hurt.

 

[Len]

So here's the story:
I currently own a JVM410H together with an AFD100 and recently added a mesa mark V to the collection.

The AFD is currently on sale, and now I'm stuck with the following dilemma: do i sell the JVM as well, and get a SC20H for classic marshall tones or do i get the JVM modded to loosen up, and sound more old-school?

My major gripe with the JVM is the fact that it sounds very compressed (especially the crunch channel), but love the fact that it's so versatile.
The SC20 on the other hand is plug and play, but needs an overdrive pedal in front to get into thrash territory.

I'm looking for classic/old-school Marshall tone (guns 'n roses, ac/dc, iron maiden, ...), that crunching Marshall sound.
For modern heavy stuff I'll be using the mesa mark V.

Your input is greatly appreciated.

I tried for years to mod a JVM for a more classic Marshall tone, but never got there. I say sell it. Life’s too short.

 

[Moony]

If you have enough money on hand maybe just buy a SC20H and then compare it to your JVM and see which one you like better.
Then sell what you don't want to keep.

I personally wouldn't trade a JVM for a SC20H.
The JVM is Marshall's flagship amp since ~15 years for a reason.

 

[spacerocker]

The AFD didnt get the old school tones? I was gonna say Id sell the JVM but maybe it would be better to just use the money from the AFD sale to get an SC or 2203/04 (marshall or clone) and see if they will work for you before you ditch the JVM.

I'm sure the OP would like the rhythm sound of a 2203/4 - but then he would be into the rabbit hole of adding all sorts of transistorised pedals in an attempt to get a decent lead sound, and would lose all the versatility of the JVM

I know JVMs are cheaper in Europe but here in the states it just seems weird to me to have to mod a amp that costs so much. I would also worry about resale and just whether the mods would make things less reliable.

Yes - it does seem weird - but at the end of the day, there isn't any other amp around with the capability to sound as close to an 800, after a few simple mods! The JVM circuit in Crunch Orange IS the 2203 circuit (with a few component value changes), as is the power amp....

Mods (done properly) will have zero effect on reliability, and can easily be reversed back to stock - so no effect on re-sale value either!

I just did the neg feedback to mine, very simple, and it opens it up more, channel 2 is not overly compressed. The only mod I did. I would try that first, cheap n easy just need a pot.

You don't even need a pot! The effect can be checked by just disconnecting the little 2 pin connector on the speaker output PCB, or by soldering a resistor in series with R86 (91K for 2203 level neg FB, I use 300K)....

 

[spacerocker]

Btw, does anyone have some sound clips of their modded JVM? I'm interested in the NFB and anti compression mods to let the amp breathe a bit more

True, but he is not chasing the next tone, he is chasing the JCM800 and if I am not wrong, the best amp to do that is a JCM800.

For those who think a JVM can't "Do" 800 tones, have a listen to this clip - This clip is a comparison of my 1980 2203 and my JVM410H in Crunch Orange. The clip is in two parts, one is JVM, the other 2203. Can you tell which is which? More importantly, which one to you prefer?





My JVM at this point only had 1 or 2 mods....

 

[maxxi]

For those who think a JVM can't "Do" 800 tones, have a listen to this clip - This clip is a comparison of my 1980 2203 and my JVM410H in Crunch Orange. The clip is in two parts, one is JVM, the other 2203. Can you tell which is which? More importantly, which one to you prefer?





My JVM at this point only had 1 or 2 mods....

If I had to guess, I'd say part 1 is the 2203. Part 1 is also the sound i prefer out of the two, but only slight. If part 2 was indeed the JVM, it seems like it would be better to get it modded. Do you remember what mods had been done at the time of recording this?

 

[spacerocker]

If I had to guess, I'd say part 1 is the 2203. Part 1 is also the sound i prefer out of the two, but only slight. If part 2 was indeed the JVM, it seems like it would be better to get it modded. Do you remember what mods had been done at the time of recording this?

Part 1 was in fact the JVM410 on Crunch Orange. Part 2 was the 2203. Both recordings were done with the same cab (a 1968 4 x 12), without moving the mic. I like Part 1 better too!....

I didn't have many mods done at the time. If I remember it was just the "Plexi mod" (which is quite subtle) a 10H Choke, and the "anti-compression mod" (which only affects the OD Channels Orange and Red modes anyway!) Since then I have added the negative feedback mod and the AFD mod (which are great mods, by the way!)...

 

[scozz]

Part 1 was in fact the JVM410 on Crunch Orange. Part 2 was the 2203. Both recordings were done with the same cab (a 1968 4 x 12), without moving the mic. I like Part 1 better too!....

I didn't have many mods done at the time. If I remember it was just the "Plexi mod" (which is quite subtle) a 10H Choke, and the "anti-compression mod" (which only affects the OD Channels Orange and Red modes anyway!) Since then I have added the negative feedback mod and the AFD mod (which are great mods, by the way!)...

I got it right,…. even listening on my phone I could hear the difference! And I don’t have that great of an ear either, but just as soon as you hit the very first chord, I said that’s NOT an 800.

 

[marshallmellowed]

In a recording, or mic 'd, I can make just about any Marshall I own "sound" like a 2203. Hell, my Axe Fx sounds like a 2203 in recordings or direct live. It's when you're standing in front of a 4x12 that the difference becomes obvious. My opinion, not the opinion of others, so no need to get crazy here.

 

[scozz]

My view, or approach, is probably different from many here, I much prefer simple amps, amps without a lot going on as far as switches and buttons, and the like. I’ve always preferred one channel amps, I like to use the guitars volume.

I’m sure Jvms are great amps, but I don’t want or need a 4 channel amp. Same deal with a 6100, just looking at all those buttons and controls make me think, there’s so much to go wrong or bad. Lol.

I never liked switching channels in the middle of a song either, it’s not, and never was optimal imo. It’s just my personal preference, I like simple single channel amps with minimal buttons and switches.

I’m just “old school” I guess, is that still a thing?

 

[Jethro Rocker]

You don't even need a pot! The effect can be checked by just disconnecting the little 2 pin connector on the speaker output PCB, or by soldering a resistor in series with R86 (91K for 2203 level neg FB, I use 300K)....

Yeah, I just used a pot so it is variable. At about 11 oclock on the dial it is about where an 800 is in NFB.

I’m just “old school” I guess, is that still a thing?

I guess. If you're old!!

 

[spacerocker]

In a recording, or mic 'd, I can make just about any Marshall I own "sound" like a 2203. Hell, my Axe Fx sounds like a 2203 in recordings or direct live. It's when you're standing in front of a 4x12 that the difference becomes obvious. My opinion, not the opinion of others, so no need to get crazy here.

I agree to a point - but I spent 23 years standing in front of my 4x12 powered by my 2203, and 13 years standing in front of a 4 x 12 powered by my JVM. There is no significant difference (when using a comparable channel/mode). Just my opinion, of course (based on my experience with both amps.....)

My 2203 is on a shelf behind me. My JVM410 is the amp I play through live....

 

[spacerocker]

Yeah, I just used a pot so it is variable. At about 11 oclock on the dial it is about where an 800 is in NFB.

Yes - to be honest, I did as well!

I was just making the point that you can do the mod without a pot, which makes it more easily reversible....However, I n practice, I never adjust it, and it is set permanently at 500K. When I modded my 205C, I just used a 300K resistor in series with R58!

 

[Moony]

If the JVM410H was 1200 bucks in the US (like it is in the EU and UK) almost everyone here would buy one.

I personally don't like the JVM with much less nfb.
I've once talked to Dan Gower he also prefers the stock value.
I have only slightly less nfb on mine, not in 800 territory.
But that's a matter of taste of course. Doesn't hurt to try it out.

 

[spacerocker]

If the JVM410H was 1200 bucks in the US (like it is in the EU and UK) almost everyone here would buy one.

I personally don't like the JVM with much less nfb.
I've once talked to Dan Gower he also prefers the stock value.
I have only slightly less nfb on mine, not in 800 territory.
But that's a matter of taste of course. Doesn't hurt to try it out.

Absolutely! I like mine with even less negative FB than a 2203! But I play classic and space rock, and like the looser, wilder feel of less FB. I also like a 10H choke for the same reason! But I am well aware that everyone has different tastes, and a lot of folk like the harder, super-tight feel of the stock amp - particularly for modern metal!

 

[Moony]

But I am well aware that everyone has different tastes, and a lot of folk like the harder, super-tight feel of the stock amp - particularly for modern metal!

To be fair I need to say that I play the 50W JVM2 so that's not as stiff as the JVM4 to begin with.
Iirc I have a 100k or a 120k instead of the 82k - tried the whole range and then saw what I like and settled on a fixed resistor.

 

[marshallmellowed]

I agree to a point - but I spent 23 years standing in front of my 4x12 powered by my 2203, and 13 years standing in front of a 4 x 12 powered by my JVM. There is no significant difference (when using a comparable channel/mode). Just my opinion, of course (based on my experience with both amps.....)

My 2203 is on a shelf behind me. My JVM410 is the amp I play through live....

Yeah guess it also depends on the 2203, as they varied in tone over the years. The JVM's I've played through all sounded pretty much the same, as later Marshalls are much more consistent in their quality control. I had a 2203 from the 80's that didn't have near the punch of my 2203x reissue. Neither my modded 410H or modded 410HJS had the punch of the 2203x. Like you stated, just depends on personal experience.

 

[maxxi]

Absolutely! I like mine with even less negative FB than a 2203! But I play classic and space rock, and like the looser, wilder feel of less FB. I also like a 10H choke for the same reason! But I am well aware that everyone has different tastes, and a lot of folk like the harder, super-tight feel of the stock amp - particularly for modern metal!

is 176K (jcm800 value) that loose? I would prefer not to drill into the chassis to mount an extra pot, so i would simply ask my tech to replace the resistor. Thus getting the value right the first time is quite necessary 😅 Also, the tone from the video posted earlier is the ballpark tone I'm aiming for, the guy did have his transformers replaced by MM ones how much would that affect his tone?

 

[Moony]

the guy did have his transformers replaced by MM ones how much would that affect his tone?

Before you consider swapping the transformers please watch a few demos of the 2203 KK (Kerry King JCM800) - it has the same transformers as the JVM410H.
I need to point that out every now and then because the 2203KK is considered to be "one of the best 800s ever made" also by guys who usually prefer the "vintage stuff" and say that the transformers of the JVM are "crap".
So it's more the circuit that makes a difference!