soundstream

[Hexhclass]

This amp blew the rail caps.I replace all the TO.92 transistors on the driver board along with R79 and the 10k that normally burns.The 150k test ok.The rail voltage increases when gain it turn up.Any suggestions?

 

[seankane]

Well usually a bad driver can cause a rise in rail, but you stated you replaced them all. There should be a regulation circuit for the rail voltage which has something out of tolerance. I wish I could be of more help, not very familiar with these amps.

 

[Perry Babin]

Are both rails increasing in magnitude or only one?

Black probe on negative speaker terminal.

 

[Hexhclass]

Only negative rail goes up.