| pat allen |
Among all the things i already asked on this board, i have a Infinity BU1 amplified subwoofer that is also burned.
It is almost all SMT design so some transistors dont have part number on them.
Is there a schematic available somewhere?
I have done several mesurements, tested almost all the transistors and resistances in it...it plays, but with a lot of distortion and one of the output, the one that is on the b+ gets very hot.
Did try to locate the bias circuit but no results.
The preamp seems to be part of the global amp feedback. If i inject signal after the preamp stage, it plays with no distortion, but still get very hot on the b+ q and barely get 1w of output power.
I have changed 2 of the smt op amp wich are plain 4558.
Something went wrong with the psu as the po did add big caps and changed the power transformer.
Any help would be very appreciated.
Pat Allen |
|
|
|
