Music Hall a15.2 Loud Buzz

cozger

New Member
Hello everyone!

I recently picked up this amplifier to give it a go to repair it. I used to play around with audio equipment and I figured this would be a good return! I am certainly not an expert but hopefully I'll learn a thing or two on the way.

Anyways, the amplifier turns on but it starts to make a very loud buzzing sound after couple seconds. It feels like it starts when the amplifier engages the speakers. The buzz is carried out to the speakers but I only tried for couple seconds since I didn't want to damage the speakers. It is coming from the right channel of the amplifier and most likely from the transistor area but I can't pinpoint what component. I've taken some measurements of the transistors and the voltage on this channel seems to be slightly lower. I can also feel the vibration around that area when I touch the heatsink. I touched up some of the connections around the transistor area just to make sure but I don't think this is due to a bad connection. Can anyone help me to understand what is going on here? Is it the caps? Or the white ceramic component that I am not exactly sure what it does? Thanks for helping out an amateur!

Please see the pictures and the video
YvoNRhk
https://imgur.com/a/YvoNRhk
YvoNRhk

 
Last edited:
Back
Top Bottom