PPIMV isn't always the best choice!

[Dallas Marlow]

Hey all,

I just had an amp tech put a pre-phase inverter standard master volume on my Heritage Colonial, and I have to say it's everything I was EVER looking for in this amp. My original plan was to get a PPIMV but he told me they didn't sound as good in this kind of amp as a PreMV so I trusted his judgment against everything I've seen/read here and other forums etc, and man I don't regret it for a moment, I have no idea how much different the PPIMV would sound but honestly I can't imagine the amp sounding any better than this one does right now, it's simply incredible. It sings, it's got amazing feel, it's just so 3d and beautiful and all at decent volumes!!! This amp now has the Marshall tone in my head, the most pure amazing incredible tone I've always wanted is now available at a decent volume, this thing simply SMOKES now, it's not grainy or buzzy, it does everything you expect a master volume to do, and the guy did a killer install job and had it done with a one day turn around. I'm going to try and get some clips up for ya'll soon, but honestly it's the best sounding classic Marshall sound I've ever heard.

But I just want people who do their own amp mods etc. to know that the PPIMV isn't necessarily the "best" one I don't feel I've had any tone suck what so ever and when the pot is on 10 it sounds as far as I can tell exactly like it did when it wasn't even in the circuit, but now I can actually get a bit of grind and crunch out of the amp with out having it at ear bleeding volumes.

Hope this will help someone who's looking into a MV mod, oh and btw this amp is a jtm/plexi/bassman clone with switches to change the circuits to their different values of the amps, and it has a negative bias feedback knob to change the feel as well.

Let me know your thoughts on this stuff!

Dallas

 

[Anonymous]

I'm glad you like the master the tech put in, however, a PPIMV would sound great in that amp as well. I don't know why the tech would say it wouldn't sound as good - that doesn't make sense. PPIMVs work great in Super Lead/JTM style circuits.

Of course a PPIMV is going to be a lot more work to install than a pre-phase master, so maybe that was why he dissuaded you.

Either way - if you like it, it doesn't matter...

Steve

 

[Rufus Leaking]

I've got as JTM50 clone here in which I'd like to install both at once - a pre and post PIV master.... I just need to figure out how

I've had both a Lar/Mar and Rich mod PPIV installed in Marshalls before and found they get too farty / wooly with a lot of gain. I've heard the pre PIV type are a bit tighter.

 

[Dallas Marlow]

I hear ya. I like the PPIV master because I can max out the pre-amp to get the needed gain. A "pre" phase inverted doesnt allow it. If I didnt use the PPIV master, I would use a Jose master with diodes. Glad you are liking the amp.

Yea for sure, I imagine you can get a good bit more gain out of a post phase inverter, but I gotta tell you man, I can get some incredible crunch outta this amp and it sounds NATURAL, very much unlike the way a master on a JCM800 sounds this thing works perfectly!!! Thanks dude, yea all that matters is it works great for this amp, they are all different beasts!

 

[dstroud]

I've had both a Lar/Mar and Rich mod PPIV installed in Marshalls before and found they get too farty / wooly with a lot of gain. I've heard the pre PIV type are a bit tighter.

I never liked any PPIMV that I've had.

+1. I got 2 amps with PPIMV's and I don't like using either one. I just leave 'em on 10 and use an attenuator. Sounds much better IMO...

 

[Dallas Marlow]

I'm glad you like the master the tech put in, however, a PPIMV would sound great in that amp as well. I don't know why the tech would say it wouldn't sound as good - that doesn't make sense. PPIMVs work great in Super Lead/JTM style circuits.

Of course a PPIMV is going to be a lot more work to install than a pre-phase master, so maybe that was why he dissuaded you.

Either way - if you like it, it doesn't matter...

Steve

Hey Steve, hope all is well with you and that new amp build is looking killer can't wait to hear some clips of it!!!

He told me general consensus on the Hoffman amp forum and his experience, at least, was that regular master volume sounded better, and obviously this is one of those things that is to taste, but I have the schematic for a PPIMV, and he knew exactly where to put it in and all when we were looking at the amp, and it's really not THAT much more work, you just move the two resistors off the board and onto a dual gain pot, but what he did was very clean and simple and really didn't take many wires at all, so yes it is less work but neither is horrible haha. He took pics of the work he did inside the amp and it looks like it's been there the entire time, even had the right chicken head knob to match so I can't complain He's a pretty stand up guy and I don't think he'd do that at all!

Haha and you nailed it as long as I dig it, doesn't matter in the end, I just wanted to people to know Pre-MV can sound fantastic, it sounds incredibly natural!!!

 

[Dallas Marlow]

I've had both a Lar/Mar and Rich mod PPIV installed in Marshalls before and found they get too farty / wooly with a lot of gain. I've heard the pre PIV type are a bit tighter.

I never liked any PPIMV that I've had.

+1. I got 2 amps with PPIMV's and I don't like using either one. I just leave 'em on 10 and use an attenuator. Sounds much better IMO...

Yes this MV is very tight sounding, isn't wooly or farty at all, and when it's at 10, it sounds just like the amp sounded before, way to clean and louder than piss haha. I'm glad others have heard some of the same things about PPIMV as well, I think it just really depends on how much gain and stuff people are going for, and I've also heard that some amps sound HORRIBLE with PPIMV where as others sound great, and some sound really bad with a pre-MV as well where as obviously ones like this one just come to life. This amp was so loud before it was borderline unusable, now it's probably going to take the #1 spot ahead of my diezel as my main amp.

 

[dstroud]

I've had both a Lar/Mar and Rich mod PPIV installed in Marshalls before and found they get too farty / wooly with a lot of gain. I've heard the pre PIV type are a bit tighter.

I never liked any PPIMV that I've had.

+1. I got 2 amps with PPIMV's and I don't like using either one. I just leave 'em on 10 and use an attenuator. Sounds much better IMO...

Yes this MV is very tight sounding, isn't wooly or farty at all, and when it's at 10, it sounds just like the amp sounded before, way to clean and louder than piss haha. I'm glad others have heard some of the same things about PPIMV as well, I think it just really depends on how much gain and stuff people are going for, and I've also heard that some amps sound HORRIBLE with PPIMV where as others sound great, and some sound really bad with a pre-MV as well where as obviously ones like this one just come to life. This amp was so loud before it was borderline unusable, now it's probably going to take the #1 spot ahead of my diezel as my main amp.

I didn't have any problem with the quality of distortion, it was more the voicing of the amp. When I turn down the PPIMV, I lose a lot of mids and low mids - the amp starts sounding more scooped. That's my issue with the 2 amps I have ppimv's on. they are both Marshall superlead type circuits. I'm glad your's worked out - I'd love to like the ppimv!

 

[Dallas Marlow]

I've had both a Lar/Mar and Rich mod PPIV installed in Marshalls before and found they get too farty / wooly with a lot of gain. I've heard the pre PIV type are a bit tighter.

I never liked any PPIMV that I've had.

+1. I got 2 amps with PPIMV's and I don't like using either one. I just leave 'em on 10 and use an attenuator. Sounds much better IMO...

Yes this MV is very tight sounding, isn't wooly or farty at all, and when it's at 10, it sounds just like the amp sounded before, way to clean and louder than piss haha. I'm glad others have heard some of the same things about PPIMV as well, I think it just really depends on how much gain and stuff people are going for, and I've also heard that some amps sound HORRIBLE with PPIMV where as others sound great, and some sound really bad with a pre-MV as well where as obviously ones like this one just come to life. This amp was so loud before it was borderline unusable, now it's probably going to take the #1 spot ahead of my diezel as my main amp.

I didn't have any problem with the quality of distortion, it was more the voicing of the amp. When I turn down the PPIMV, I lose a lot of mids and low mids - the amp starts sounding more scooped. That's my issue with the 2 amps I have ppimv's on. they are both Marshall superlead type circuits. I'm glad your's worked out - I'd love to like the ppimv!

I know exactly what you mean I played a JCM800 that way, where it was nearly a useless extra nob, and it was just this thin brittle harsh sound when you keep it at lower volumes. And yea it def sounds very scooped, so I 100% know what you mean, I wonder why some amps agree with that mod and others don't? Interesting stuff tube amps are!

 

[johnny q]

I've had both a Lar/Mar and Rich mod PPIV installed in Marshalls before and found they get too farty / wooly with a lot of gain. I've heard the pre PIV type are a bit tighter.

Hmmm...I feel the same way about my 1972 Superlead w/ the Rich Mod, the bass really farts out. The strange thing is, I still crank the thing to unGodly volumes to get the tone I want, so why even bother having a MV....might just get it DE-modded.

 

[Dallas Marlow]

I've had both a Lar/Mar and Rich mod PPIV installed in Marshalls before and found they get too farty / wooly with a lot of gain. I've heard the pre PIV type are a bit tighter.

Hmmm...I feel the same way about my 1972 Superlead w/ the Rich Mod, the bass really farts out. The strange thing is, I still crank the thing to unGodly volumes to get the tone I want, so why even bother having a MV....might just get it DE-modded.

I HIGHLY recommend you at least try the Pre-MV mod that was done to my amp, it was the most simple mod I've ever seen it only took like two wires and an extra pot, that may be an exaggeration but seriously the before and after pics, barely anything changed, it's just like a line run off the middle of the treble pot and and then another line run some where else, I'm not a tech so I can't tell you exactly but it's just a normal old school MV and it sounds great, I can dial in everything from Hendrix to AC/DC to any classic marshall tone now, add in a boost pedal and I can hit damn near anywhere. It's not a TON of gain, but it's great!

 

[Rufus Leaking]

I've had both a Lar/Mar and Rich mod PPIV installed in Marshalls before and found they get too farty / wooly with a lot of gain. I've heard the pre PIV type are a bit tighter.

Hmmm...I feel the same way about my 1972 Superlead w/ the Rich Mod, the bass really farts out. The strange thing is, I still crank the thing to unGodly volumes to get the tone I want, so why even bother having a MV....might just get it DE-modded.

I HIGHLY recommend you at least try the Pre-MV mod that was done to my amp, it was the most simple mod I've ever seen it only took like two wires and an extra pot, that may be an exaggeration but seriously the before and after pics, barely anything changed, it's just like a line run off the middle of the treble pot and and then another line run some where else, I'm not a tech so I can't tell you exactly but it's just a normal old school MV and it sounds great, I can dial in everything from Hendrix to AC/DC to any classic marshall tone now, add in a boost pedal and I can hit damn near anywhere. It's not a TON of gain, but it's great!

Can you post pics?

 

[JTyson]

I've heard both that sounded good, so I'm officially on the fence

 

[steve_k]

Doesn't Jerry at FJA do this on the Plexi mod? Sounds pretty good to me.

Steve

 

[Dallas Marlow]

I've had both a Lar/Mar and Rich mod PPIV installed in Marshalls before and found they get too farty / wooly with a lot of gain. I've heard the pre PIV type are a bit tighter.

Hmmm...I feel the same way about my 1972 Superlead w/ the Rich Mod, the bass really farts out. The strange thing is, I still crank the thing to unGodly volumes to get the tone I want, so why even bother having a MV....might just get it DE-modded.

I HIGHLY recommend you at least try the Pre-MV mod that was done to my amp, it was the most simple mod I've ever seen it only took like two wires and an extra pot, that may be an exaggeration but seriously the before and after pics, barely anything changed, it's just like a line run off the middle of the treble pot and and then another line run some where else, I'm not a tech so I can't tell you exactly but it's just a normal old school MV and it sounds great, I can dial in everything from Hendrix to AC/DC to any classic marshall tone now, add in a boost pedal and I can hit damn near anywhere. It's not a TON of gain, but it's great!

Can you post pics?

Lemme call my tech today, he was supposed to email the pics he took and showed me at his house but I think he got busy, I'll let you know asap. I'm looking online because I know I saw the schematics for what he told me he did, honestly it's really basic... I'll update it for you when I find it ok man?

 

[Dallas Marlow]

I've heard both that sounded good, so I'm officially on the fence

That's the crazy part, I've heard different types of MV sound anywhere from amazing to horrible on different types of amps, I was reading some where it's kind of a crap shoot because you never know what your going to get haha.

 

[Dallas Marlow]

Can someone help me out with a wiring diagram for him, I can't find it for the life of me but this is just a simple pre phase inverter master volume it's just a couple wires and a pot?

Thanks,

Dallas

 

[Rufus Leaking]

Can someone help me out with a wiring diagram for him, I can't find it for the life of me but this is just a simple pre phase inverter master volume it's just a couple wires and a pot?

Thanks,

Dallas

Thanks, but don't go to any trouble. I know all that stuff is out on the Metro forum, I just have to get off my ass and do some searching...

 

[MrDan666]

Can someone help me out with a wiring diagram for him, I can't find it for the life of me but this is just a simple pre phase inverter master volume it's just a couple wires and a pot?

Thanks,

Dallas

It's the same Master Volume that's in the JMP/JCM800 2203 amps, just a 1M pot (Audio Taper) fed off the Treble wiper and the Master's wiper goes to the .022uF PI Input cap.

Here's the schematic:
http://www.drtube.com/schematics/marshall/2204prem.gif
http://www.drtube.com/schematics/marshall/2204pwrm.gif

 

[Dallas Marlow]

Can someone help me out with a wiring diagram for him, I can't find it for the life of me but this is just a simple pre phase inverter master volume it's just a couple wires and a pot?

Thanks,

Dallas

It's the same Master Volume that's in the JMP/JCM800 2203 amps, just a 1M pot (Audio Taper) fed off the Treble wiper and the Master's wiper goes to the .022uF PI Input cap.

Here's the schematic:
http://www.drtube.com/schematics/marshall/2204prem.gif
http://www.drtube.com/schematics/marshall/2204pwrm.gif

Sweet thanks MR Dan much appreciated, hopefully this is what he needs, btw do you have your channels jumpered? because this amp has both ch on at the same time already and I just turn their volume up equally.

Dallas