Hi. I try to build a 100 W guitar amp. I purchased the Project 27 board from Rod Elliot which works fine when I use a frequency generator or an iPod as input. But when I connect the preamp to it, it starts oscillating. First I thougth the preamp layout is bad, but the funny thing is that the preamp works fine on its own. So when no load is connected to the preamp it works fine, no oscillation. I measured it with an oscilloscope and it does exactly what it should. But as I said the whole thing starts oscillating when the pre- and the poweramp are connected. I used shieled leads as input, as connection between pre and power, and also as output to the speaker jack.
Its my first DIY amp and I really dont know what to do. Could you help me ? Should I post pictures from the whole thing ?
Its my first DIY amp and I really dont know what to do. Could you help me ? Should I post pictures from the whole thing ?