Transistor Q691 is turned OFF by the overload detection circuit. This puts
R691 and R692 in series with the B- for the driver IC's. The resulting
voltage drop causes an imbalance of the power supplies to the drivers. When
the signal swing bumps up hard against that rail, the signal is then
asymmetrical enough to trigger the DC detect circuit. Kind of ass-backwards,
but it gets the job done. In practice you would really have to get all those
speakers jumping (in surround mode only, really) to trigger the thing.
Like I said, it's a "feature" , not a malfunction.

Mark Z.


"Jimmy" wrote in message
...
How would you go about finding the voltage drop on the one - rail?

I didn't follow you on: "The voltage drops on the one rail to the drivers,
not the outputs."

My thoughts on removing the driver(s) was just to check and see if the
voltage would still drop.

Thanks
Jimmy