My prefered Marshall so far . . .

[duesentrieb]

A guy wanted me to mod his 2 channel JMP a bit more. It had a clean channel(eq on the back) added ages ago. I've maxxed out the gain for the crunch, added a 4th gainstage, a second master and now its a three channel fucker.

That thing sounds huge Those old transformers are unbelieveable good.

Here are the guts "after" I've crapped the shit out of it

Posting that esp. for Psychodave - to tell him that adding this kind of turretboard on top of the original board stands IMO is a cool way to expand an amp without drilling even more (you wanted to install a loop, right?). And there's enough room for switching and circuitry.

 

[maiden_fan]

Hey olaf, you seem to be quite the modding guru.

Is it possible to do the soldano mod you recommended for the 1980 jmp 100?

Or do you have recommendations for the jmp in terms of mods, other than a PPIMV?

cheers tony

 

[1big1]

hi olaf. i wish i had your knowledge and skills when it comes to tweaking amps.. but then i wouldn't be me!
nice job.. per usual. rawk on.

 

[duesentrieb]

Guru for the poor

Hi Tony,

I'd rip a 2205/2210 completely apart und install a whole new PTP board with 2.5 channels, keeping the clean (using a Fenderish approach) - and something like in this amp, two masters, two gainpots, one eq and crunch/lead switchable with 3/4 gainstages. And a loop of course.

Jeff Seal, who at least was a regular at HCAF knows much more about modding 2205/2210s, but the latest stuff I saw from him were also full rebuilds - keeping the transformers only.

There are some mods for it out there (I had two for mods here, but I gave up fast - while the poweramp can be changed to "normal" specs pretty fast (the PI is different), the whole preamp needs to be changed.

 

[duesentrieb]

Hey olaf, you seem to be quite the modding guru.

Is it possible to do the soldano mod you recommended for the 1980 jmp 100?

Or do you have recommendations for the jmp in terms of mods, other than a PPIMV?

cheers tony

A "normal" 2203, Tony?

 

[duesentrieb]

hi olaf. i wish i had your knowledge and skills when it comes to tweaking amps.. but then i wouldn't be me!
nice job.. per usual. rawk on.

Hi Dave, thanks a ton. have a great weekend !

 

[simbasa]

Very nice!!! I want!!!

 

[maiden_fan]

its a non master volume jmp that is in the HC classifieds.

sorry about the editting lol, thought i could change it before you posted.

After reading up on the 2205/10's i dont think i would like them in comparison to my old superbass.

 

[duesentrieb]

You can do a million things to a non-MV, Tony.

Keeping it as it is and just install Larry's version of a PPIMV, which is nice in two gainstage amps, which are bright - the PPIMVs fucks the presence, which is ok for these bright monsters. I pretty much prefer the Jose master in those and keep the negative feedback, which IMO is a huge part of the Marshall sound.

The full Jose mod is nice too (with the diodes) - but both have the prob. that he amp is pretty limited to what you do with your axe - its just one/two sounds at different levels, you know . . .

I like the multi designs better, adding a good real clean, a meaty crunch and a lead which is more a beefed up crunch with its own master - just keep in mind that you don't have too many ways to change the amp due to its chassis. Of course one still could do this, like the Über-Guru did:

And I prefer to mod already hacked/modded JMPs. I'd be in tears if I had to drill into a clean JMP, you know . . .

 

[Cornfordcrunch]

God I wish I knew how to tweak my own stuff...Of course that would then open an entirely new bag of "seeking" and that would be bad.

 

[MrDan666]

Nice work Olaf as always!!!! I like the idea of adding that turret board there like you did, to save adding more holes

 

[maiden_fan]

I was trying to keep the mods as reversible, ie when i had the PPIMV on my superbass i used one of the speaker line out holes to do it.

Im just trying to get ideas at the moment, the tone im aiming for is similar to John sykes recent live tone. I saw him in thin lizzy and his tone was epic, really huge and just the right sizzle if you get my drift. These are the kind of marshall tones i like

https://www.youtube.com/watch?v=QgU-bygBlvM

https://www.youtube.com/watch?v=fHmu9k6W ... re=related

https://www.youtube.com/watch?v=TWUwP8LZrAg

Any hints or guides would be great im ok with a soldering iron and can navigate my way around a circuit diagram
many thanks

 

[maiden_fan]

What would be the differance tone wise between the 'jose master' and the 'rich mod' in which both i assume are PPIMV type mods?

I think i might just do one of these and see how the amp sounds from there.

thanks

 

[MrDan666]

What would be the differance tone wise between the 'jose master' and the 'rich mod' in which both i assume are PPIMV type mods?

I think i might just do one of these and see how the amp sounds from there.

thanks

Tony,

the Jose master isnt a Post phase inverter master, its a pre phase inverter master. So its earlier in the circuit, just before the tone stack.

I find the PPIMV to be looser on the bottom end and darker sounding, whereas the Jose Master to me sounds much better for high gain tones and stays pretty tight. Even sounds a little bit gainier to my ears, i would imagine with the diodes it adds a bit more hair too! Sykes's Jose modded 800 probably has the Jose Master or atleast a variation, as Jose did that type of master quite a bit.

Here's a Jose Arredondo modded 2203 schematic, which Mark Cameron said will get somewhere close sounding to Sykes's amp and it uses the Jose Master with the diodes.

https://img.photobucket.com/albums/v485/mrdan666/arredondo1.jpg

 

[duesentrieb]

I was trying to keep the mods as reversible, ie when i had the PPIMV on my superbass i used one of the speaker line out holes to do it.

Im just trying to get ideas at the moment, the tone im aiming for is similar to John sykes recent live tone. I saw him in thin lizzy and his tone was epic, really huge and just the right sizzle if you get my drift. These are the kind of marshall tones i like

https://www.youtube.com/watch?v=QgU-bygBlvM

https://www.youtube.com/watch?v=fHmu9k6W ... re=related

https://www.youtube.com/watch?v=TWUwP8LZrAg

Any hints or guides would be great im ok with a soldering iron and can navigate my way around a circuit diagram
many thanks

Over at Metro is a thread where Mark Cameron joined and said that going into Sykes direction the Jose mod wold be close to be perfect. Add a tube, cascade, add the post-CF master with the diodes and in a Superbass I'd decrease the PI coupling caps from 100nF to 22nF.

There's isn't a layout for that yet, but a schem. Let me know if you have probs to "understand" it.

 

[duesentrieb]

LOL - I was just preparing diner for the kids . . . Thanks Dan !

 

[MrDan666]

LOL - I was just preparing diner for the kids . . . Thanks Dan !

No probs Olaf I hope i got the info right there.. im still learning as i go along with this stuff!! I was totally new to amps and mods about a year and a half ago, and now im finally starting to truly understand how it all works.. with the help of guys like yourself!!

 

[MrDan666]

Olaf, quick question for ya

my 50w JCM800 has an extra hole punched in the chassis for an extra preamp tube. Its placed between the stock v2 and v3 tube sockets.

If i wanted to add an extra tube infront of V1 like in the Jose mod, could i move all the tube sockets along and use the original v1 socket for the extra stage? i mean like move v1 to v2, v2 to the extra hole and leave v3 where it is... then use the original v1 socket for the new tube.

 

[duesentrieb]

Olaf, quick question for ya

my 50w JCM800 has an extra hole punched in the chassis for an extra preamp tube. Its placed between the stock v2 and v3 tube sockets.

If i wanted to add an extra tube infront of V1 like in the Jose mod, could i move all the tube sockets along and use the original v1 socket for the extra stage? i mean like move v1 to v2, v2 to the extra hole and leave v3 where it is... then use the original v1 socket for the new tube.

Of course you can do that, Dan. I suggest to get one of the 220x layout by Billy Batz to get the wiring correct.

 

[duesentrieb]

What would be the differance tone wise between the 'jose master' and the 'rich mod' in which both i assume are PPIMV type mods?

I think i might just do one of these and see how the amp sounds from there.

thanks

Definitely. The PPIMV adds compression and at lower levels disengages the Presence. The Jose-Master is a bit more transparent than a standard post-tonestack master (think 2203) and keeps the presence.