Audio Research DSI 200 integrated amp

That's very interesting, thanks. I wonder if was running out of headroom or something.

Yes. The dynamic headroom was indeed restricted. It was just a poor match for my speakers, MBL 121,which were a bear to drive - low sensitivity at 84 dB with impedance dropping to 2 ohms at times. The Mac power does not double with halving of the impedance.

I did a lot of testing with the final conclusion that the ARC DSi 200 is pretty much unbeatable in its price range.  The best thing to do is to listen and not be influenced by the circuit's topology.  Many people speak without listening and speak ill out of pure prejudice.

I own one and really like it