Mike M.

Hi,

I love the chunk of my JCM800 2203x R.I., but it's still a bit too too harsh and brittle when played at low volumes. I've seen where the brite cap can be removed. There's a pretty good explanation of what it is and how to do that at the link below:

Tales From The Tone Lounge; The Ultimate JCM800?

When you remove the cap, do you just snip it off and leave it that way? Do you put a different cap in its place? It seems pretty easy to do but I ain't exactly an electronics wiz, so I want to be sure of what I'm doing before I do it and make sure it's worth it.

For those of you that have done it, does it help?

Any help would be greatly appreciated.

Thanks.

PaoloJM

This cap can be removed completley. Removing the bypass cap on the 470k for the low input is up to taste so do one at a time and see how you like it. Trying different cap values in their place is a also a great idea. Higher values pass more bass but don't go too high or you'll render the volume pot useless!!
I also changed the 470k value but that value's going to remain a secret!!
If I was you I'd de-solder the cap properly so that it can easily be replaced later and restore the amps stock value.
Another common mod, to restore full tone at low volume, is to install a 100k resistor on the wiper of the master volume pot. This lessens the bass freq roll-off at lower volumes.

Mike M.

Thanks PaoloJM. I'll probably just start with removing the brite cap and see what that gets me, then go from there if I have to. Sounds like a pretty simple job.

Good reminder on desoldering it completely!

mmorse

I've clipped the brite cap and replaced the treble peaking circuit with a 68k carbon comp resistor ala Tone Lizard. I was thinking of doing the 100k resistor on the master volume pot also. Can you tell me what 2 tabs on the master volume to solder the resistor to? I'm assuming the middle tab on the pot gets one leg. Where does the other leg of the resistor get soldered to? The left tab or the right tab? Or does it go someplace else?

thanks