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Re: JCM800 4210 - post-PI MV, switchg Xtrs

10/5/2005 1:48 PM
Doug	Re: JCM800 4210 - post-PI MV, switchg Xtrs I don't have a resistor after the gain pot before the grid, might try it out, I yanked out the bright cap. As far as the cathode follower, I would have used one but I wanted that tube to be the third gain stage before the eq. The old circuit sent the boost channel and the clean channel through valve 3a (a shared gain stage) I routed the boost channel around 3a right into the .022 coupling cap off the 3a plate. I also put a 3n3 cap in series with the presence, I found that mod somewhere on the web, now it acts like a deep bass resonance. I don't know the science, I just tinker til it works. Did you pull out the clipping diodes? I put in a toggle switch so I can add them back between stage 2 and 3 of the boost channel. Also stage 1 bypass cap is now a 22uf, that sweetened the whole thing up and I put a .68 bypass on stage 3. Doug

10/5/2005 1:48 PM

Doug

Re: JCM800 4210 - post-PI MV, switchg Xtrs

I don't have a resistor after the gain pot before the grid, might try it out, I yanked out the bright cap.

As far as the cathode follower, I would have used one but I wanted that tube to be the third gain stage before the eq. The old circuit sent the boost channel and the clean channel through valve 3a (a shared gain stage) I routed the boost channel around 3a right into the .022 coupling cap off the 3a plate.
I also put a 3n3 cap in series with the presence, I found that mod somewhere on the web, now it acts like a deep bass resonance. I don't know the science, I just tinker til it works.

Did you pull out the clipping diodes? I put in a toggle switch so I can add them back between stage 2 and 3 of the boost channel.
Also stage 1 bypass cap is now a 22uf, that sweetened the whole thing up and I put a .68 bypass on stage 3.
Doug