Review: Accustic Arts Reference Tube Hybrid DAC II DA converter


Category: Digital

This will be my third go around reviewing a DAC from the German company Accustic Arts. In between having the MK-3, MK-4, and now their Reference Tube Hybrid as my digital front end, I have had the pleasure to auditioned many of the highest regarded DACS and CDPS in the last couple of years. Many of this digital pieces offered great performance, a few were sonic "turkeys" regardless of some steller reviews, but based on great performance without having to get a second morgage to purchase it, I keep coming back to Accustic Arts.

The MK-4 was a significant improvement over the MK-3 and I still believe it's one of the finer sounding DACS around today. That's way I was skeptical about how much better/different would Accustic Arts new "baby" would be compared with their older DAC.

As in all my reviews I do not get into specifications, you can go to Accustic Arts website to get the details, but always comment on build quality and physical appearance. Like its older siblings the Tube Hybrid is just beautifully built and really is "eye candy". The German engineering and craftmanship is very easy to admire. I know one important technical aspect that this is the first DAC in the world that does not use tubes in the analog section, but somewhere further upstream when bits are still bits before the analog conversion stage. What the tubes are doing and how they are used in the overall design circuitry I don't have the foggist notion, just that sonic bliss is taking place.

When I discovered that Accustic Arts new reference would use tubes I was somewhat concerned for the following reasons: 1) My past experience with tube based DACS, such as the Zanden and a very high level Audio Note, was that they offered a very wonderful midrange but they lacked macrodynamics and extension on both the top and bottom ends. 2) The transparency/clarity and very small details I love in the overall sonic perspective of my system were lost.

SONIC PERFORMANCE

I do not like to result to sonic cliches to describe the sonics of a piece I'm reviewing, but this DAC is a "killer"! I hope all of us can agree that once you get to a high level of excellence in audio gear, their are many great pieces and differences become more quantitive then qualitative. We also have to factor in personnal taste and system synergy in to the equation. Taking all of this into account let me try to explain way this is the best digital I have heard in my system to the present time.

1) The Tube Hybrid retains all of the transparence/clarity and microdetails of the MK-4.

2) I will not say that the Tube Hybrid's extension on the top and bottom are better then the MK-4, but the the overall slam and dynamics is slightly more "lively" and natural sounding. Remember, the MK-4 was no slouch in these sonic areas to begin with.

3) Now we get into the specifics of why the Tube Hybrid is a "killer" in qualitative terms.

A) Unlike adding a "warm/euphonic" aspect to the music this DAC adds what many would call a touch of "bloom/fullness" without destroying the overall linear cohesiveness of the sonic perspective. Another more concrete way of saying it would be that image density and the overall harmonic structure ( leading edge, body, and decay trails) is more natural or what alot of audiophiles would dscribe as "analog" sounding.

B) This DAC offers an overall more sense of liquidity and smoothness, but not at the expensive of slam/punch/dynamics or sounding "soft" to be pleasing to the listener.

C) I have a hunch that another reason why the Tube Hybrid sounds more "real" is that it is more tonally linear compared to the MK-4, and any other digital piece I have heard on Redbook, which makes it sound of one piece top to bottom.

D) The Tube Hybrid offers the most natural timbres I have ever gotten from a digital front end.

E) I don't believe that my system's overall soundstage dramatically improved with the Tube Hybrid, the MK-4 was a champ in this area, but the layering and the air around players also went to a qualitatively higher level.

When I wrote a review here on the GON on the Stealth Metacarbon IC's I struggled to use words to describe the sound of "nothing", meaning these cables just get out of the way of the music so the illusion of real music being played by real people just gets spills into your mind and gut. Well, this DAC hits my sonic ear's the same way, it just sounds more like real music then I have ever heard in my listening room before. The Tube Hybrid sonics can be broken down into specifics, as I have tried to do, but its the overall natural/easy/lifelike sonic illusion without the loss of details,prat,sparkle that makes this a very special piece indeed.

I always end all my reviews with the statement their is no "BEST" in high end audio, but many fine pieces along with the factors of personal taste and system synergy. The new Accustic Arts Tube Hybrid DAC II is among one of the finest DACS on the market today, and while it is not inexpensive it competes with DACS triple its price. This German company sure has some talented thinkers with great ears when it comes to digital gear. If your in the market I highly recommend you audition this DAC before you purchase another.

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teajay
Hi,

I am currently using AA Drive 1 MK1 + DAC 1 MK2, and consider to upgrade to Drive 1 MK2 + DAC 1 MK4. Will Drive 1 MK2 + DAC1 MK4 sound more mechanical and hifi compared with Drive 1 MK1 + DAC 1 MK2? I just a bit worry abt the this upgrade will cause the sound too forward and not natural enough!
Cykeric, the short answer is no, it won't sound too forward and not natural enough.

Read my review of both pieces for the details why both pieces, Drive 1MK2/DAC 1MK4, will be an improvement sonicly over the prior generation.
Thanks very much Teajay.

However, your review is on AA tube dac and the comparison is on AA tube dac with MK4, not MK1/2 with MK4.
I notice there are 2 versions for tube DAC II. One is tube DAC II ref, and the other is tube DAC II SE. Which one is more updated?? The outlook is also diff. One is without "tube" wording on the top, and the other is. So, which one is SE and which one is ref?? Thanks.
Cykeric, I'm a little confused, I did GON reviews on both the DAC 1-MK4 and the Drive 1-MK2 which compared them to the first generation AA pieces, not the Reference Tube Hybrid DAC. Take a look at them, if you have not already.

Regarding your question about what is the difference between the tube DAC 11 and the SE version, the SE version uses some higher tolerance parts and supplies you with what are called special "NOS quality tubes". Well, at least the SE unit I heard came with JJ 12AX7 tubes, which ain't special, not NOS and sound like crap. The sonic difference between my DAC 11 and the SE version was my DAC sounded better with the tubes I use, NOS 12AX7 Amerex Bugle Boy long plate G getters. If I was buying new right now I still would buy the tube DAC 11 which sells for around $1200.00 less then the tube DAC 11 SE and go out and buy some great NOS tubes, cost would be around three to four hundred dollars, save alot of money and still have a DAC that out performs the more expensive model. This DAC's sonic performance is greatly effected by what tubes you use. So for my money I want to pick what NOS tubes that give me what sonics I'm looking for. So, in my opinion the change in a few parts or their working tolerances did not make any significant sonic inprovement, but without casting aspersions towards either AA or the US importer the DAC SE I experienced did not come supplied with NOS tubes, I guess the JJ's are better then the EH stock tubes in the DAC 11 but they both are crappy sounding, and you are supposely spending some of the extra cost on NOS tubes provided by AA. Can't answer your question regarding the top cover, the units I have seen all have the craved out tube design.