hello, i build a jfet based preamp and i found that on a transistor amp the signal gets about doubled but wen i plugged it into my jcm900 it was louder when i putted it on passive than when i used it! so i pluged my guitar in the effect loop on the back and there it was louder on the preamp again!
howe is this possible? (on the normal input it was less loud then the passive but i did lose quite a bit of hum from the long cabele and stuff.)