I got to compare the A21, Coda # 8 and Krell 300xd in my system. I landed on the Krell, to me it was the best of Pass and the best of Coda rolled together. All Class A, Krell kept its legendary ability to drive almost any speaker with grip, control alive with the XD gear along with a silky, grainless, smooth presentation. There is also a touch of warmth, tube magic to the Krell XD gear. Prior to the comparison I owned the A21 and Coda at the same time, had lots of time I compare the 2. I preferred the Coda but was based on my taste, the A21 for around half the price of the Coda was really hard to beat form a dollars / performance ratio.
I like you loved the KRELL Duo 175XD that I sold to buy the CODA #16. I have had the following amps in the house with essentially the same system
- Parasound A21+
- CODA #8
- CODA #16
- KRELL Duo 175XD
- Schitt Wotan ($2k)
- Benchmark AHB2
My favorite is the CODA #16 because it is almost the best on top (AHB2), it is the most powerful and overall has the best sound. The next 2 would be the KRELL Duo 175XD and the Schitt Wotan. I am not sure which I like better so call it a tie.