Sony STR-6065 clipping positive peak right channel
Hello fellow audiokarma members,
This is only my second post. I could really need some help from anyone out there in audiokarma land. I've been using this great site to repair my babies.
I'm in a bit of a jam. Let me explain. I'm getting postive clipping on the right channel speaker output (at around +10 v ). Left side a-o-k, right side buzzing at roughly at around 1 pm on the volume knob. Volume below 1pm, left and right are ok.
Here's the main amp schematic (left side here as Sony decided to leave the right side blank) :
So at the (R) main amp input differential (Q751 Base -> Q701 on the drawing above), my test 1khz sine wave is all good - no clipping. The damn cllipping seems to start at he VAS transistor (Q753 Collector -> Q703 on the drawing above).
The thing is I replaced the output power transistors with some MJ21196G's from Digikey (so no chance of counterfeits, right ?). Could my driver transistor top end 2SC895 be the cause of the clipping ? Could it be the top end power transistor MJ21196G ? Maybe a predriver ?
I sure could use a good samaritan right now,
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