« Reply #6 on: March 06, 2007, 05:01:57 PM »
Those TI opamps would be pretty easy pickins. Still not sure what those bjt devices are doing - sourcing some current for something.
The transistors are the front end, and, I believe, providing all the gain.
My opinion is that the circuit is not that good. Yes, the BJTs provide low noise, but the chosen circuit is not that good from a sound quality point of view. This might be fine for film, but not great for music.
AFAICT there are four transistors per channel. The transistors are in a differential arrangement, two transistors on each side (for more gain)? There should be two more transistors per channel for a constant current source, but they are not there. I would like to know more about this circuit. Anyone care to trace it? I *might* even consider replacing it with a high quality opamp front end. This might make it sound better (at the expense of a bit more noise).
Anyway, plussssssssssT for getting in there and messing around!
Richard
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