Evh 100 resononce mod

[Jd267]

hi guys quick question that I hope some one will be kind enough to help me with . I modded my Evh 100 to 50w chan 2 and now want to mod the amp for resononce pots for each channel have any of you guys done this ? Would love some info and pics would be awesome !

[dirty dog]

Check out the schematic on the EVH gear site it will give you the resonance for the 50 watter.

[Jd267]

Check out the schematic on the EVH gear site it will give you the resonance for the 50 watter.

How will that help with the 100 watt?

[projectx102]

The three negative feedback resistors get changed to 1 meg linear pots. That simple.

[projectx102]

R4,R5,R6 get the wires that go to the pots.

[Jd267]

The three negative feedback resistors get changed to 1 meg linear pots. That simple.

Yes that's what I was thinking but I seen how R6 has two wires and also looks like the blue wire is jumped from each pot . That pic does not show what I need . Kind of got confused after seeing that pic lol

Your pic shows 4 wires going to the three pots . That's what I do t get . Maybe the r6 pot has two wires , r5 pot get a wire from r6 pot (jumped) one to wiper and same for r 4 pot . That's what I'm thinking if you can could you confirm that? That would be killer man..

[Jd267]

Any other help would be awesome man . Is that your amp? Do you have any detailed pics of the wiring

[projectx102]

The blue wire is the ground.You only need it in that one spot because the grounds are tied on the board. Then you just tie the grounds of the three pots together.

[projectx102]

The amp pictured is not mine. Mine is modded to full Stealth specs.

[dirty dog]

It will show you how the resonance is configured. As projectx102 has said its the case of changing the fixed resonance resistor to a potential divider (pot) so its adjustable.

[Jd267]

The blue wire is the ground.You only need it in that one spot because the grounds are tied on the board. Then you just tie the grounds of the three pots together.

That's pretty much what I was trying to say . So the blue wire is ground, so on the pots center prong is the wiper so left prong is ground or right prong? Or it don't matter? I guess I could mess with my meter to figure that out.

Think I may get the idea thx for the help guy!

So only two lugs on pot will be used wiper and one of the other lugs

[Jd267]

Seems the blue wire goes to wiper and jumps to other two pots . Got it working . Wish I had some better pics but after I confirm my mod is correct I'll post actual pics of the mods so others can use it . I also bypassed r37 cathode resistor with 22uf like stealth made a good difference .

[Jd267]

The three negative feedback resistors get changed to 1 meg linear pots. That simple.

It's an audio taper pot not linear .

[Jd267]

figured I would share my mod I did to my 100 watt 5150iii R4, R5,R6 are the Fixed resistors for resonance , remove those resistors and replace them with three 1 meg audio taper pots . See my wiring as its a little weird do to the traces on the board to make a long story short .

[projectx102]

You are correct. I did use audio taper pots. There are however,a few more changes to bring the amp to stealth specs.