Mytek 192-DSD DAC vs NAD M51, Levinson 36, Phasure

Many people seem to like the Mytek 192-DSD, a very well regarded professional quality DAC at an affordable price point. See, for example:
http://forum.audiogon.com/cgi-bin/fr.pl?ddgtl&1357569392

A new option in this same price range is the Stereophile A-rated NAD M51. In this post, I share comparisons of these two new DACs with two others: an oldie-but-goodie Levinson 39 used without the CD player, so it's basically the same as the 36 + 38 analog preamp, and which is in roughly the same price range; and with the very expensive Venture Audio Phasure NOS1, which served as as our reference DAC.

Since speakers matter a great deal in any test, the two sets of speakers used were B&W 801-series III and a pair of Dale Harder handmade TLS-1, which are new remakes of the original Walsh Fs. The 801s, being a traditional dynamic speaker, ported bass, three-way system with directional tweeters are a rich sounding speaker and still, in my personal opinion, are superior to currently made 802s with the exception that they lack detail in the bass reportedly on account of a lousy crossover. The Walsh-Fs are extremely precise and unparalleled for imaging and reveal copious detail. Some feel these routinely best $100K WATTs, etc, in competitions. They do not have a flat response, however. I think they roll off pretty severely in the 10K and up range and also have a weak spots in the low midrange, but these are subjective opinions.

In the interest of full disclosure, the Walsh-Fs were driven by Spectron III and the 801s by McCormak DNA-1 -- two very differently made, but both very clean and transparent amplifiers.

As a matter personal bias, I should say up front that my preference is for enormous detail, moderate imaging, and accurate timbre, but not at such an extreme that one sacrifices silkiness. In that sense, I am predisposed to like highly detailed DACs as opposed to more tubby sounding systems.

The Mytek DAC was able to resolve layers of instruments better than any other DAC I tried. The NAD was and Phasure were roughly tied for second, which was a pretty remarkable achievement for the NAD. The Levinson garbled on complex passages, but it's a much older and lower-bandwidth DAC. This was a big plus for the Mytek and very exciting.

With the ultrasonic filter set to sharp, the Mytek was closest to the Phasure in spatial resolution and placing instruments distinctly on the sound stage. The NAD and Levinson both sufficient but unremarkable in this regard. The MYTEK put everything in front of the speakers. The NAD put everything well behind the speakers.

I'm inclined to believe that ultra-high frequency and phase information play important roles in imaging, and the Mytek's very fast and untempered performance in the treble provided an aggressive, live-performance realism. The sound stage was not quite as wide as the Phasure, but the Mytek was considerably more crisp in how it placed instruments on the sound stage.

With respect to timbre, the Mytek generally disappointed except with percussion. It reproduced Iz Kamakawiwoʻole's fingernail tapping on his ukelele, string buzz from violin pizzicato, and the copper overtones of timpani drums with accuracy that no other DAC matched - one could actually determine that it was fingernails and not just an arbitrary tapping. Percussion went from being simply acoustic events to having detailed, recognizable timbres. On the other side, the Mytek consistently lacked the very important woodiness of piano, cello, bass violin, and clarinet. Those wood tones give music its soul, and this was a disappointment. In heavily percussive tracks, like Pantha du Prince's "Bohemian Forrest", the Mytek basically destroyed the music by rendering the percussion perceptually about 2-3 dB louder than the melody lines, making the track an uninteresting percussion solo.

Listening fatigue with the Mytek was the worst of the four, and I presume this is the trade off for accuracy. In general, the Mytek's presentation was extremely forward and etched out and seemed almost to have an imperceptible high-frequency hiss. I thought this might go away when we moved from the 801s with dedicated tweeters that beam out treble to the Walsh Fs style TLS-1s that have very diffuse treble and roll off severely in the ultra-high frequency range. Unfortunately, the harsh quality persisted with the Walsh Fs as well and now seemed layered on top of everything. By comparison, the NAD was very laid back, silky smooth. The NAD was weighted too heavily to the upper-bass for the 801's juicy bass reflex, but turned out to be just right for the Walsh Fs.

By comparison, the Levinson and Phasure provided a nicer balance that worked well on both systems. I suspect these differences have something to do with the audio reconstruction filters. Here it would be nice if Mytek and NAD could offer several options in a future edition.

I really appreciated all the other options in the Mytek DAC that were not available on the NAD, such as ultrasonic filter choices, upsampling choices, etc. Ninety-five percent of the time I'm not going to switch modes, etc., but sometimes you know that a particular piece of music wants something different, and it's great the Mytek offers that. I also really appreciate the option to use the Apple remote.

Mytek has a couple of killer flaws. One is that it sends a big DC pulse on use of the power switch. Mytek confirmed that this was a known issue. It sent my power amps into self protection mode, and frankly I think it's dangerous, especially in very high-end systems where people have enormous amplifiers. Also, beware that the levels come defaulted to 0dB, which is about 6dB higher than what most manufactures call 0dB (you can change this with jumpers) so be careful on first use that you don't blow your system up.

All three of the listeners who joined me agreed that the NAD won out over the Mytek. The fellow who owns the Walsh F's and Phasure, was extremely excited about the Mytek as he had read about it, but within three minutes into listening he was done and already feeling listening fatigue. I was consistently hooked by the detail popping out here and there, but constantly wanted to turn the volume down because I felt I was getting a headache. Even after extended periods of no listening (first listening of the day, for example) this tiring effect showed up within just a minute of listening to the Mytek. This proved the be the achilles heel for this new and otherwise awesome DAC.

By comparison, I generally found the NAD to be too laid back for my taste. All the detail was still present, but it was quieter and not as lively. In many ways, this might honestly be what one wants for most casual listening; but it's not the audiophile presentation.

The Levinson and Phasure showed a balance, but the older Levinson lacked the detail and separation that the new NAD had. There were times I preferred the Levinson over the NAD, and times when the opposite was true. If your speakers are not particularly bright or revealing, like the 801s, the NAD may prove to be too laid back in its presentation. In such as case, it might be more sensible to experience the compromise on detail in complex passages than to have the sound sit too far back on a regular basis. However, for very forward, revealing speakers, like the Walsh-Fs, the NAD was a good match.