if they are on the bottom sounds like maybe some LNFB (local negative feedback loop). Although i don't believe the regular OTS amps have them, but you said you had extra switches added, so that may be the case. The adjust the frequency response of the amp.

Gregg

They're not standard, and as such don't have a standard setting. You're going to have to get in touch with the person who built the amp, or the person who added them, and find out what the different settings are for.

Search for pickmaster mods. Its his originally. I have them on mine. Installed them myself.

Thanks that was very helpful.  I was wanting a fat amp and very scared of it being too high pitched because I love bass and smooth mid with a little compressed overdrive/gain similar to a Santana or some of Warren Haynes Mesa sounds.  Nik did build the amp and answered my request by installing 3 way bright switch, 3 way mid boost, and "snubber switches V2".  Those snubber switches must be just what they are.  My question then can I flip these while the amp is on to test out the sound?  I apologize if these are stupid questions.  I am a player and play very well but I am not an electrical engineer.  At least I am trying right   I know this amp will be perfect for my playing needs and I understand most of how to operate other than a few things and like I said before I just don't want to blow anything up. Any of you coming to Indianapolis?  Drinks on me!!!!!