The Audinst HUD-MX1, as always, sounds very musical. With the 2-ch Beta22 and the Hifiman HE5LE, I noted no deficiencies in the Audinst’s sound output. The sound is slightly warm, there is a good body and musicality in the music. The soundstage information is very good, separation very good. For sure, the Audinst still remains a very good performing DAC for the price it’s selling for.
Moving to the MusicStreamer II, the first impression that strikes me is how soundstage has been improved. Most notably is the soundstage depth, where the MS2 is much more three dimensional than the Audinst. The width and the open-ness of the sound is also improved on the MS2. I am liking the improvements a lot, as soundstage performance is very important to me. The instruments are more alive and independent, where the HUD-MX1 still maintains everything fairly close together.
Furthermore, the two DACs are also different in terms of sound signature, the Audinst HUD-MX1 has a more relaxed and slightly warmer sound signature. The MS2 is more neutral, and doesn’t quite have the coloration of the Audinst. The MS2 is also more lively and energetic. Treble is more decisive on the MS2, and bass is tighter and punchier. I’m not saying that the Audinst is highly colored, because it’s still mostly a neutral sounding DAC, but it’s warmer and more relaxed in comparison to the MS2. Depending on system synergy, some people may prefer the Audinst’s more relaxed and warmer sound. The MS2 is more forward, although with a Beta22 and the HE5LE, I don’t feel the HUD-MX1 to be overly laid back.
Again, little differences between the two DAC. The HUD-MX1 has slightly more low end presence, but bass punch is less tight and less punchy, where on the MS2, even guitar plucks sound more decisive and snappy than the HUD-MX1. Vocal is slightly more forward on the MS2, with richer texture, where the HUD-MX1 is smoother and slightly more laid back.
Going up to the $345 model, the MS2+, does yield some nice improvements, although they are more subtle and more in the small refinements. The MS2+ has an even bigger soundstage, a more refined treble, and slightly more midrange body for a more musical sound than the MS2. The subtler improvements is very appreciated on a highly transparent system such as the Beta22 and HD800/HE5LE that I’m using, and the MS2 sounds quite less refined and a little harsh than the bigger brother. On lesser transparent systems, I’m not sure if the difference is going to be that noticeable.
What matters more in this comparison, (at least from a practical standpoint) is how the Audinst come with quite a decent headphone out that’s able to drive big impedance cans such as the HD650 and the HD800. That makes it a very convenient unit, as you don’t need the clutter of another headphone amplifier. The Music Streamer II, on the other hand, is more of a purist approach. If you own a high quality headphone amplifier, you’ll probably like the Music Streamer approach better, as it just give you a high quality digital to analog conversion for pairing with your headphone amplifier. Otherwise, the Audinst would be preferable, because you don’t need to worry about getting an amplifier, as the built in amp is quite competent.