Finest dac I have ever heard PERIOD. I wrote quite a bit about it and my findings but the powers at AGON killed the thread. In my opinion upsampling has NEVER EVER sounded right (even when all the magazine gurus were busy telling us how superior upsampling was) and that includes the 64 bit upsampling in my beloved Pure Music. No other dac has sounded as real or pure as the Metrum. The Concert fidelity dac (USD 10K) is a fine unit and it pales in comparison to the Octave and it has tubes in the output stage; not that that means a thing :) Tubes are no panacea and most times they can obscure purity with a false fattening of the musical event. Now I also have an AMR DP777 with about 11 days on it and I will state that it is nearly equal to the Octave (remember the AMR is NOT yet fully run-in). The AMR is an awesome sounding unit and a huge value for the money.
You absolutely can't go wrong with the AMR or the Ocatave, I have heard a great number of very very expensive dacs and most of them are nothing more than the stock circuit (supplied by the manufacturer) of the dac chip employed with little changed and in some cases it is verbatim. Don't let anyone fool you. A fully run in Octave (minimum of 4 weeks) will go head to head with anything I have heard in 14 years of being involved in this hobby. The only thing I have heard thus far to come close to it is the AMR.
You absolutely can't go wrong with the AMR or the Ocatave, I have heard a great number of very very expensive dacs and most of them are nothing more than the stock circuit (supplied by the manufacturer) of the dac chip employed with little changed and in some cases it is verbatim. Don't let anyone fool you. A fully run in Octave (minimum of 4 weeks) will go head to head with anything I have heard in 14 years of being involved in this hobby. The only thing I have heard thus far to come close to it is the AMR.