Hi, im going to build an amp, and well, i want to use it without any pedals, kinda a amp to carry around, but the original schematic doesnt include a gain pot, possible due to few gain stages, it has just 2 gainstages in the preamp.
so what im thinking is to add an extra tube, so adding 2 more gainstages and between the two put a pot to control the gain.
now my doubt is, can i "just" add like that? or i have to see if, i dont know, the transformers will suporte the extra efford or something...
thanks 

Hey, i've build a ruby amp some time ago, but now i wanted to used it too drive some headphones. my doubt is if i connected "directly" the ruby to some headphones would i "kill" the speaker?? do i have to in some way soften the signal? i wanted to control also the distortion so the connection would be made after the chip... dont know if im making any sense.. 
thanks all

hello all! i have some doubts about where to place the effect loop in an amplifier. the only thing i know is that the signal circuit should be away from the power, but where exatly should i put the effect loop? right next to the input jack? a bit far away, after the eq. pots?
many thanks

Hello all, i have a pcb layout from a schematic that i done in the diy layout creator, and when i was to print it, using the option render PnP, the image it creates its too big! how do i put it to "real" size??
thanks