I've been using the DB Audio Labs Tranquility followed by the Tranquility SE NOS DAC for the last few years. Originally, all my music files were AIFF CD quality (44.1 kHz/16 bit) managed by iTunes/PM. Currently, my system includes a Mac Mini (2011, 2.7 GHz core i7, 8 GB RAM), El Capitan, PM3 software and a wywires USB cable.
More recently, I started downloading and accumulating higher resolution AIFF files, so I begun contemplating a DAC that could read them. Since I have no plans on getting into DSD that playback capability was not an issue. My good experience with the very musical Tranquility plus the idea of no digital filters led me to Metrum Acoustics.
The Octave, Hex, Pavane and Musette models have all received favorable reviews. I called Hi-Fi Heaven, the US distributor and when they offered me a very reasonable trade-in for my Tranquility SE decided to order the Musette.
The Musette comes in a very simple but attractive box about the same size as the Tranquility. It has more digital connection options including USB (hiFace TWO, 44.1-384 kHz). Included in the package are a USB stick with instructions, a generic power cable and a USB cable.
My first negative surprise after plugging in the Musette, connecting the USB cable and choosing the USB input on the front was the fact that the hiFace option didn't show up in System Preferences. Then, after switching the power on/off on the Musette and rebooting the Mac without a different result slight panic started to set in. I vaguely recalled reading about El Capitan and USB.
Next, I changed USB cables and decided to try the generic "high-speed USB" cable supplied with the Musette and to my great surprise hiFace TWO showed up in System Preferences Sound Output. The music was back like magic. However, this is not the end of this story. After the Musette worked well all evening and I shut down my system at night (the Mac goes into sleep mode) the following morning there was again no DAC option in System Preferences. All my rebooting, turning the DAC on/off had no effect. The only thing that worked was physically unplugging the USB cord and plugging it back in.
But when the Musette worked how did it sound. Well, my only comparison is the Tranquility SE. Without burn-in the Musette's overall character is equally musical and more refined even with CD quality material. The highs are more extended and the bass seems to reach a little lower. One very noticeable trait in my system is the spaciousness of the sound. The end effect for me was even on 44.1/16 material a sense of being more resolving.
And even without burn-in I could hear absolutely no harshness.
The high resolution files I have (mostly 96/24 and 88.2/24) are a treat. There is no comparison. The Musette is much more detailed, musical and refined. I really like the tone. On complex classical music the instruments are more fleshed out and the timbre just seems right.
Finally, I contacted the distributor about the El Capitan USB issue. Cees Ruijtenberg of Metrum responded within a day. He stated that it was an issue with Xmos USB chips and how Apple has changed the audio handling within the operating system. His advise was changing back to Yosemite or Mavericks. This didn't seem a good option for me.
Another email from the distributor explaining how the Xmos chip functions revealed, however, a simpler solution for me. If you shut off the computer, the next time you start it up the Xmos chip (in its' own sleep mode) receives the 5V charge and is reset to connect and becomes visible to the operating system. The System Preferences then recognizes the DAC and all is well.
So, in summary, sorry for the long post but let me say that I love the Musette.