vintageHIWATTconvention.com

Hello All,
Newbie here with a question. I came across this Hiwatt 50 dated to 1980 with this crazy mod on the front panel. After a few hours scouring the web, i could not find anything about it...so here i am and i would like to thank anyone who helps me in advance

The mod is a selector switch with 5 positions and as I turn the knob counter clockwise it increases the gain for both channels but brings the level down for the master. Im not sure how this is supposed to work...
I have included pictures of the chassis and mod in hopes that someone here can identify it. Maybe tell me who did it? Looks like it was done factory...
Thank you!
David

Well, that's definitely not factory (although neatly done). Interesting paint-covered circuit board in the middle. It looks like "Glyptol," an old insulating paint/covering used in the middle 70s.

Thanks!
Yeah... i didnt want to take the red stuff off until i had some eyes on it. If i cant get any answers here i will take it to my amp guy and ask him to decipher it for me. It looks like some kind of slave for the master volume...