The output buffers are Non-feedback. For low impedance, we applied a diamond output stage which is quite less colored than most conventional circuits.
The low gain says it uses diamond differential. If that's correct, I guess that means you can use the NFB-11 to compare ACSS vs diamond differential. The discontinued ref 3 (and their cd players) had transistor vs acss, and I thought it was an interesting comparison, with transistor being more exciting but less trufhful. If you think the high gain is too revealing, I suggest trying out the low gain stage.