Help with amp mod!

[Notuern]

Pleading to you guys who know your stuff about amps to help me modding my Randall RM100 module!

Its the SL+(Hotrodded JCM800.), that i want tighter / more modern sounding.

Here is the schematics: http://dl.dropbox.com/u/876568/SL_1.pdf

Now, the mod im considering now is the following:

R31 changed to 33K
C13 changed to 470pf
C3 changed to 22u

IF possible, i would like to the tone-stack voiced more like the Soldano SP77(And some more attack would be nice.): http://www.freeinfosociety.com/electronics/schematics/audio/soldanosp77preamp.pdf

I really dont know that much about this stuff, but i figured since its a modular amp, i cant hurt my self tinkering with the module it self.
And IF i f*ck it up, i can just give it to the local TV-repair man(Does jobs like that cheap as Jesus purple nippled tits.).

 

[Notuern]

Bump? ;(

 

[ChrisTanakaCanwell]

Bump? ;(

;(

 

[Wolfeman]

Are you sure that schematic is correct? I see a lot of missing values... And a schem with the tube board on it would help.

Edit- Ok I see it lists the values on the tube board.

Are all the parts labeled 'NP' not on the board? Check the actual module and get back to me. Then I could be some help.

 

[Wolfeman]

Ok yeah they use the same pcb for most modules, so the parts listed as NP aren't in yours.

For the tone stack to be more Soldano, change-

C14- 470pF
R31- 47k

That's it for that. I'll post back with some more stuff that you were asking.

 

[Wolfeman]

Can you get me the resistor values that are 0 on the schem?

Edit- Never mind, they use the 0 ohm resistors as jumpers.

 

[Notuern]

Wow!
Thanks ALLOT! Much appreciated!

Im sorry i wasnt here to reply to your questions!

 

[Wolfeman]

No problem, those values will make it the same as the reissue JCM800 tone stack, which is the same thing in the SLO, SP77, Avenger, etc.... It will probably just change the midrange a bit.

What else were you looking for? More gain? Less gain? Tighter? Less tight?

 

[Notuern]

Thank you kind master!

The gain is pretty much where i want it to be.
What im aiming for is a modernized version of this tone:


Neil Kernon claims it was a stock Marshall 1969.. so yeah, a mix between that one and a Soldano is basically what i want!

Tight, dynamic AND great separation.
I use allot of dynamics when riffing, and i really like it to "pop" when i hit the strings HARD.

If it helps, i could record a few clips of it tomorrow, to "show" what i want changed.
Thanks again!

 

[Notuern]

So i got to record a short clip today:

http://dl.dropbox.com/u/876568/whatitsound.mp3

All knobs set at noon, recorded through the fx-loop and i used s-preshigh for cab-sim.

 

[Metaltastic]

So i got to record a short clip today:

http://dl.dropbox.com/u/876568/whatitsound.mp3

All knobs set at noon, recorded through the fx-loop and i used s-preshigh for cab-sim.

WAY too much flubby lows IMO, and undergained :/

 

[Notuern]

WAY too much flubby lows IMO, and undergained :/

Actually, its not under gained, its because of that preamp getting such insane amounts of low end it sounds weak and flubby.
Basically, thats what i want to fix with it.

(If it wasnt clear, that was the unmodified module.)

I think that both the brown and SL+ modules are undefined as f*ck.. thats why i was so disappointed by this amp.
BUT the SuperV sounds AWESOME(Based on Lynch's modified Vox AC30): http://dl.dropbox.com/u/876568/voxmodule.mp3
This is boosted as f*ck with the SD-1 though, i use it for lower gain stuff.. but think a mix of that tone and a Soldano, thats what im aiming for(Im not planning on playing Thrash or anything on it. ).

 

[Metaltastic]

Ah, I didn't realize that was the unmodified one, cool - and I can definitely imagine some sort of low-cutting OD pedal would help, but I can definitely hear potential with it, so I'll be curious to hear how it sounds after the mod!

And yeah, that Vox model sounds pretty sweet indeed; a touch metallic, but not unbearable (could be from the pickup)

 

[onqel]

Since it's modular it gets a little complicated, if it was a "normal" amp you could reamp your DI's through spice with different tonestack setups to find the values you're looking for (close at least) but you need the schematic of the host system to do that with your randall

 

[Notuern]

Well then, bring it on! >;D

http://mtsforum.grailtone.com/viewtopic.php?t=4324&sid=a3d53d85dde03b45483a225346f06eb6

 

[Wolfeman]

The issue isn't with the tone stack, it's the filters between the stages that need to be modified.

 

[Notuern]

Truth.
So Spice cant render the differences there? ;(
But yeah, ive been recommended to drop C3 down all the way to 01u.. do you think thats a good idea? Or is it too bright then?