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Van Alstine Ultra DAC Review

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In comparison to the Monarchy M24, another tube design, the Ultra Dac is rather abrupt with the highest frequencies. Cymbals, triangles, chimes and bells – this may seem like a harsh term, but is accurate – are a bit truncated. There is less connection between cymbal taps; they are heard more like miniature explosions within their own acoustic envelopes. Not to a tremendous extent, but marginally the Ultra Dac presents music in a more staccato fashion than the M24.

“Many audiophiles adore this closeness to the instruments, and if that is what you prize, you will be ecstatic about the Ultra Dac’s ability to get very close to the source.”

Spatial clues to the size of a recording venue are also less dramatic. The result is a “closer” feel, a more powerful burst of sound from the moment of impact, the instant the breath passes the reed, etc. This reminds me very much of the MIT AVt MA speaker cables and interconnects, which draw the listener into the physical immediacy of the event. Many audiophiles adore this closeness to the instruments, and if that is what you prize, you will be ecstatic about the Ultra Dac’s ability to get very close to the source.

There is a cost associated with making a DAC this way, and the cost is extension. An example is Bob James’ “Ashanti” from his Restoration: The Best of Bob James, where through the Ultra Dac drumstick strikes have diminished reverberation, finding expression primarily instead in the explosive moment of contact. When I put the M24 back into the rig, I could much more easily hear the after-echo of the impact reverberating in the recording. Conversely, there is a slight cooling of the tonality with the M24, as it did not have as golden a tone as the Ultra Dac. These are not necessarily critical details for many music lovers. One might prefer to have warmth at the cost of a smidgen of extension – a very personal choice.

Another instance of the slightly damped sound of the Ultra Dac was heard on Amy Shreve’s “Diamonds from Dust,” on Piece in the Puzzle. The harp is a good instrument in assessing the ability of a component to expose the freedom, the openness of the venue. Reverberation, pace and extension of soundstage all play critical roles in enjoyment of solo harp recordings. The Ultra Dac ever so gently warmed the sound of the strings but also dampened them. The recording venue shrunk to the stage, whereas with the M24 the entire hall was in play. Years ago I played guitars strung with either nylon or steel, and as I listened it sounded as though the Ultra Dac had Amy’s harp strung with nylon while the M24 gave her steel. Steel strings have more snap, tension, and sound more powerful when plucked, and the M24 responded in that manner.

AVA-UltraDAC-3

16-Bit 4X Oversampling

It may seem as though I have been pretty tough on the Ultra Dac. Does that mean I feel its performance is poor? No, not by any stretch, but I believe it is limited by the design choices Frank Van Alstine has built into it, a case in point: the 16-bit parallel processing. The decision to limit word-bit length and sampling limits the results this DAC yields. There is truth to the AVA literature when it advises that CD players acting as transports make not that much difference. However, the reason why is critical; any signal fed to the Ultra Dac is forced into 16-bit four-times oversampling. Because it is incapable of scaling up for higher-end signals, it negates the benefits of DSP in newer players. I found this out as I compared the two DACs in question. The M24 can handle 24-bit/96 kHz signals and it sounds like it. The depth, detail, clarity all are influenced by superior signal treatment. The Ultra Dac simply struggles to compete at that level. In fact, it forces the stratospherically upgraded 24-bit/384 kHz signal of the Cambridge Audio Azur 840C player into the 16-bit mode. I found this out when I attempted to compare the sound of the upsampled signal of the Cambridge to its “Pass Through” untreated signal – and found that they both

sounded exactly the same through the Ultra Dac. Once the Cambridge’s supercharged signal hit the Ultra Dac it became the same signal (for all intents and purposes) as that yielded by the “Pass Through”, having been forced into the 16-bit parallel processing. So, yes, there is far less of a distinction between transports feeding the Ultra Dac, but only because of the limitations it puts on the signal.

When I asked Frank about this, he responded, “Since the CD itself is a 16-bit signal, how it was previously recorded makes no difference.” One can see his perspective is that no advantage can be had by upsampling – 16 bits is what the disc has, and 16 bits is what his equipment employs. Conceptually, this is an infallible argument, but I have heard upsampling players and DACs which emit upsampled signals sounding more refined than 16-bit.

All of this jousting about bit rates can be good news or bad news, depending on where you are in your audio addiction. For readers with a modest CD player, the Ultra Dac is a godsend. It will take your lowly signal and upgrade it to marvelous tube splendor. For those with higher end players, it will likely be irrelevant whether the Ultra Dac would extend performance. This is especially so since the Ultra Dac is hamstrung by the elimination of an IEC. On principle Frank eliminated it, but my reviewing experience has shown invariably that certain aftermarket power cords make a tremendously effective upgrade. Even at the limited 16-bit level, the Ultra Dac could improve significantly if an IEC were used.

Transports

I have heard too many things to be convinced by any objective argument that all transports, cables etc. are ineffectual relative to the sound of the system. To lay this claim to rest I had to work out the potential “crisis of confidence” which might be caused by such strong proclamations. I needed to conduct the “Transport Test” through the Ultra Dac.

Did different transports make the Ultra Dac sound different? If Frank was right, they should sound all but indistinguishable. In addition to the Cambridge Azur 840C, I had on hand the utilitarian Oppo 970HD. In my previous review of the Azur, I compared these players through the Monarchy DAC and stated that the Oppo in no way attains to the class of the Azur. It had a much brighter and lightweight sound, one that could not really be called robust in comparison to the 840C. Theoretically, such differences might be much harder to discern through the Ultra Dac, which would have the effect of nullifying the advantages of the Azur. A result like that would threaten the upper echelon of audiophile gear and allow the lower echelon to take a solid step forward in conjunction with the Ultra Dac. Frank would be vindicated and the world would be rid of the senseless subjective notions infesting audio…

It was not in the least the case. The Oppo was confirmed once again as a polite, affordable transport, but not a high-end one. There was an obvious difference between both players; each had its personality clearly revealed. The results were consistent, paralleling these players’ use with the Monarchy. The Oppo was bright and lighter in the bottom end, while the Azur continued to be weightier and richer. I would have been astonished had the Ultra Dac neutralized most distinctions between them, and I wasn’t surprised at all that the 16-bit parallel processing did not remove their peculiarities.

The result is that it does not pay huge dividends to use this DAC with upsampling players, as the signal will be shrunk to fit the DAC. However, if you already have your trusted CD player or transport and simply wants to add an outboard DAC without spending a fortune, the Ultra Dac might be the ticket. Indeed, an “econo-audiophile” (I do not use that term derisively, as I was one for more than a decade!) might just see it as their salvation.

Finally, tube rolling is a moot point with the Ultra Dac. Each of the 6N1P tubes lend their tonality without driving the load, in what Frank calls the “Transimpedence circuit.” As a result, Frank explains, their service life is excellent and they will not significantly alter the sound from gain changes, “…aging will not cause significant sonic degradation.” However, there are no practical alternatives to this tube. In some applications, a 6DJ8 or 6922 could be used, but Frank in his inimitable way conveyed the problem, “The 6DJ8 will work, but the sound turns to mud.” My investigative mind wondered if doing any change, including a non-recommended tube change, would yield a result which passed the Law of Efficacy.

Frank Van Alstine’s Ultra Dac is simple: No power cords to consider, no tubes to roll, no isolation devices to purchase – even the hard plastic feet on the unit will work as well as any isolation devices, which I would tend to agree, as the isolation devices I have used with digital sources have failed the Law of Efficacy spectacularly. The perceived change is so small as to be negligible. On the whole, time has been better spent looking into component changes over isolation tweaks.

This DAC is right for the person getting their feet wet in the world of high-end audio – someone who doesn’t give a rip about Subjective vs. Objective. It is a huge jump in sound quality from receivers and lower-cost CD players. It will knock the socks off a person who has never heard an outboard DAC. It’s hassle-free, with no moving parts and thus, longevity. It’s warm and inviting sounding, so even those with less than stellar components will likely find that it is boosting the sound tremendously. Though it is not ultimate, it is ultra, meaning beyond the norm.

Often I give general purchasing guidelines as an indicator of where a component’s best use falls. In a system with high resolution capabilities, if one has not done head-to-head comparisons with other tube DACs, I’m quite sure that the Ultra Dac would be satisfying to most audiophiles. In a rig below $5k, it will seem like a gift from Heaven! For those using $25-30k of equipment (these are generalities) and a source with very high resolution – maybe a player in the $1.5 – $2.5K range – it may seem on par but no better. My assessment is the Ultra Dac will find acceptance in upcoming first time transport and DAC users or in homes where “smooth and mellow” is king and the equipment may not change for five to ten years.

An inexplicable aspect of this review is the fact that I could not secure specifications for the Ultra Dac. I am diligent about scrutinizing the specs for a component, as there are usually interesting questions about its operation which reveal themselves. Frank repeatedly, almost monotonously referred to the measured responses, the performance parameters, the designed characteristics of the Ultra Dac, yet I never saw a single graph or chart. I scoured the website, then mentioned their absence and requested directly in my interview the specifications. I still can’t tell you how this thing measures. As all audiophiles know, measurements aren’t everything, but it would certainly help Frank out in his quest to promote the Objectivist position if he would make the measurements available!

The frustrating conclusion (frustration from what I perceive is holding it back) I draw in regards to the Ultra Dac is that it does perform at a very respectable level. In fact, it sounds amazingly good for a DAC with a toaster power cord and 16-bit processing. I would love to see Frank take this thing to the next level. If it would have an IEC and an ability to handle a 24-bit/96 kHz sampling rate, coupled with the smoothness and warmth it exudes it could be formidable! It wins reserved praise as it is, but if Frank really wants to turn the digital world on its head, he’ll need to pimp this DAC. At the current price it is a contender; if he could juice it with all those wicked, immeasurable “improvements” for about $2k, it could be a champ.

Postscript

Just as I had sent the finalized review of the Ultra DAC for publication, I received a request from Frank to hold the press. He had developed an, “unadvertised running improvement,” and requested we round-trip the unit to be upgraded and re-assessed. This addendum is my comment directed to the efficacy of the upgrade.

In correspondence with Frank, as I returned the unit I suggested a daring proposal: Would he be willing to additionally retrofit the Ultra DAC with an IEC style power receptacle to accept after-market power cords? I was tempting him to go where he did not want to; I wanted him to pimp his DAC. I knew that this would result in making it impossible to absolutely compare the two versions, however my thought was that there would be a much higher chance that the modifications would result in a significant improvement in sound.

The daring (and potentially beneficial) aspect of the proposal to him was that if the unit showed no substantial improvement following the IEC installation, I would publicly acknowledge that he had designed his DAC so as to be at the ultimate performance apart from that “cable nonsense” I kept pushing on him. However, if the unit was improved by the IEC, he would have to acknowledge it, but would also gain a viable upgrade for customers in the process.

Frank never responded to my question. In one sense, I understand the mindset, as he is a “stick-to-your-guns” kind of guy. In another sense, I’m disappointed as I proposed a “comin’ right at you” kind of challenge which was shot down. So be it; it seems that forever a regular cord will be supplied with a Van Alstine DAC.

The upgrade, in Frank’s words was, “a pretty useful upgrade to the first current-to-voltage amplifier section of the analog filter circuits.” Indeed, this was a minor improvement as opposed to a major change. As I suspected, it was difficult to hear any improvement of the unit. There were two reasons for this, the first being that there was a temporal lag to the comparison. I would not presume to consistently assess a minor change made to a component when there is a two-week gap in between, and I would hold suspect anyone who would claim the ability. However, this is only if the improvement would be minor, too minor to be easily distinguished.

This change eluded my Law of Efficacy, however that does not mean there was no improvement, only that I was not able to re-approach the unit fresh and detect a benefit. I thought at moments that I may have heard a bit more crispness in the treble, a slight tightening of the bass, but I could have no certainty of it.

This is precisely why I developed the Law of Efficacy, because in many cases no concrete change is detectable. In such cases, decisions to “defer judgment” are useless; if you can’t hear the change now, what makes you think you’ll hear a significant change later? Decisions to purchase equipment never should hinge on thoughts like, “Give it two weeks to break in,” or “The bass will improve remarkably over time.” Many readers may want to play the incremental upgrade game, but not me. It’s got to be significant, which means easily and immediately distinguishable.

Having said that, in one last pairing not previously tried the unit proved to be adept. I used the tube-based Ayon Audio CD-3 as a transport to the Ultra DAC, and I was most pleasantly rewarded. A very holistic, rich tube timbre combined with clean presentation resulted. The bass presence was particularly fine, and I felt like I was listening again to a permutation of the sound of my dear Pathos Classic One MkIII tube integrateds in mono configuration. The oddity of it was using a $6K player with a $1,700 DAC. Even though this would not be the norm for gear hunters, it brought up the intriguing possibility that the Ultra DAC might perform strongest paired with a tube CD player.

Had Frank accepted the proposition and refitted his design with an IEC, things might have been different, as I am fairly certain the distinction in sound would have had a much better chance of passing the Law of Efficacy. But Frank doesn’t believe in after-market power cords in his own designs, and for fairness’ sake, he may be right, although I doubt it.

However, if you think Frank is right, and don’t want to spend money on things like premium power cables, then the Ultra DAC is for you, as it will provide lovely, solid tube performance with no frills.

Manufacturer’s Comment:

Please thank Doug for us for a mostly very positive review of our Ultra DAC.
I am however, concerned about a couple of things.

First, after a couple of readings of the eleven page printout here, I became a bit curious about the “signal to noise” ratio of the review. I highlighted all the lines containing actual comments about the musical performance of the Ultra DAC and came up with about one page of text worth of the eleven page printout. There were lots more space devoted to wondering why we don’t use magic cables and power cords, for example.

We don’t because they are at best worthless, and at worst downright dangerous (such as if the magic power cord builder got his polarities wrong and defeated the built in protection against a hot ground short circuit).

We were also surprised that the reviewer did not hear much difference with the upgrade we made to the unit to bring it up to our current product. This did take the slew rates up and the distortion down in the current-to-voltage amplifier sections about 3 orders of magnitude. We suspect that would be audible to anyone, unless of course the interconnect cables being used were not musical enough. 🙂

However, overall Doug painted a nice picture of the Ultra DAC. I guess most of our customers are not buying $20,000 worth of each component, and our niche is to supply great musical performance to those that want real world rational prices and performance without paying for frivolous extras.

One final thought; the current capacity of the shielded toroid power transformer is more than twice that ever required by the circuits. In addition, there are eight separate regulated power supplies. We do pay attention to what is important.

Thank you,
Frank Van Alstine

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