Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => Preamps and Effects => Topic started by: slobrain on February 21, 2007, 06:41:40 PM

Title: Peavey Renown, Preamp mods for gain channel, Any one have?
Post by: slobrain on February 21, 2007, 06:41:40 PM
Hello,
I'm new to the forum but an old ampager for the tube amp stuff. I wanted to ask by chance if any one here has ever modded any peavey preamps namely the distortion channel?

I've tried different dual op-amps but this doesn't seem to change the distortion character
but I haven't tried different clipping diodes.

Thanks

SLO
Title: Re: Peavey Renown, Preamp mods for gain channel, Any one have?
Post by: joecool85 on February 21, 2007, 07:41:33 PM
Diodes is where it's at for modding distortion.  I haven't done anything with peavey preamps, but I've played a ton with a transistor based overdrive of my own and diodes is where it's at.  If you want a mean metal type distortion/overdrive, try using LEDs.  Different color LEDs react differently (to an extent), I use RED ones.
Title: Re: Peavey Renown, Preamp mods for gain channel, Any one have?
Post by: slobrain on February 21, 2007, 09:10:21 PM
Hey Joecool,
Yeah, the red LED's are good to try. Seems I remember the rockman using led clipping to get a good distortion. Actually the amp does have a pretty good distortion but its kinda dated in a sense. The funny thing is..there is a diode bounding circuit in the preamp like the tube screamer. I've also seen this used in modding Marshall tube amps to get a better distortion. I tried that same circuit In a JCM800 clone and the diode bounding circuit worked well getting the JCM800 to a higher and smoother distortion as well.

The diode bounding circuits I've seen use anything from germanium to 1n4148 to 1n4003's and zener diodes. Lots to play from... :tu:

SLO
Title: Re: Peavey Renown, Preamp mods for gain channel, Any one have?
Post by: teemuk on February 24, 2007, 08:35:58 AM
Try the usual variations:
- Different gain
- Different clipping threshold
- Different amount of high/low cut post/pre/within the clipping stage