Review on Linear Tube Audio Aero DAC

@tksteingraber - Thanks for linking the tube thread.  Based on my web search, if I decide to keep the DAC, it seems I should be able to find a tested and matched pair of suitable NOS tubes, like SYLVANIA VT231s, for under $300, which seems an acceptable price assuming they improve the sound.  I wish LTA had those DACs in stock and ready to ship as I am looking forward to hearing it.

@teajay

Based on your comments here, and the Audiophiliac (Steve Guttenberg) review, the Linear Tube Audio Aero DAC sounds like a really great deal on a very musical DAC for $4K.

Since the LTA Aero is an R2R DAC using the AD-1865 DAC chip, I am curious whether you have heard any of Benjamin Zwickel’s Mojo Audio DACs, which are also R2R DACs and which use the AD-1862N DAC chip? I currently own both the Mojo Audio Mystique EVO Pro and Mystique X SE DACs, each of which use AD-1862N-Z chips, which were apparently a special version of the AD-1862 chip developed for high-end Denon DACs back in the day and incorporate the "Z" designation. If you have seen the Soundbsessive DAC Chip List, they have good things to say about both the AD-1862 and AD-1865 chips:

Analog Devices: Multibit:
AD1862 20-bit – one of the best of the world’s Audio
AD1865 18-bit, very good multibitnik, 2 DACs and in one case (stereo)

Although the output stages are different between the Mojo Audio and LTA models (Mojo Audio DACs do not use tubes), there are similarities beyond the AD DAC chips and R2R design, which include dedicated power supplies for each section and Belleson-regulated, multi-stage choke filtration.

I was interested to hear Guttenberg’s comments regarding the LTA Aero vs. the Mola Mola Tambaqui, since I owned a Tambaqui last year and compared it directly to the EVO Pro DAC. To my ears, the Tambaqui sounded basically "perfect" while the EVO Pro offered a sound that I perceived in comparison as more musical and fun to listen to, if that makes any sense. I also found that the Tambaqui displayed a bit more "high-frequency air and spaciousness" as described by Guttenberg in his comparison between the Tambaqui and the LTA Aero. However, in my system, the relatively small differences in high-frequencies between the Tambaqui and EVO Pro were overshadowed by my favorable perception of the EVO Pro displaying more tonal color and body. After listening to both over an extended period, I ended up selling the Tambaqui and kept the EVO Pro.

If you have heard any of the Mojo Audio Mystique DACs, from the v3 on up, I would be interested in hearing your thoughts on how those compare with the LTA Aero.

Nice review.  I would like to hear the DAC.

I always appreciate seeing pictures of the insides of gear.  This thread shares the best picture of the insides of the Aero that I could find, and this article shares another.

Found this to be interesting.  Made me wonder if their choice of AD1865 vs. others like AD1862 was related to finding a chip they could stockpile in sufficient quantity.  Also interesting comments on power cords relative to power supply.  They clearly value listening as part of their design and parts selection process.

@teajay

I was intrigued enough by your review, and the many other positive responses from those who own or have heard this DAC, that I called LTA yesterday, had a nice conversation with Mark Schneider, the LTA CEO, and purchased the Aero DAC. I should see it in about 3 weeks as they are waiting on cases.
They clearly put a lot of thought and effort into the design, and there is innovation throughout the DAC beyond the Berning-modeled output stage. Mr. Schneider shared a lot of details and unfortunately I cannot remember them all. LTA are aware of similarities with the DACs from Mojo Audio such as the AD chips, Belleson regulators, and choke power supplies, and Mr. Schneider is interested to hear about my comparisons between the Aero and my current Mystique Evo Pro Z and Mystique X SE NCZ.
Since my system typically remains powered up all the time, I was interested in Mr. Schneider’s comments about warm up. He acknowledged the Aero DAC sounds better after a 2-hour warm-up, and the sound can continue to improve over a couple of days. He indicated turning the unit on/off is may be harder on the tubes than simply leaving it turned on. Also, the ZOTL circuit only uses about 1/3 of the tube’s power and the 12SN7 tubes they sourced are not dreadfully expensive.
I look forward to trying this new DAC.

@teajay 

I also used my favorite 6SN7 tube, NOS 1943 TungSol black glass/round plates. Everything in my description of the Aero DAC’s performance with these tubes went even higher.

After reading about how you found the DAC's performance to be even better with NOS 6SN7 tubes, I thought I would look around and maybe purchase a set prior to receiving the DAC, so I could maximize its performance during my 14-day trial period.  Holy crap, I had no idea of where prices have gone on 6SN7 tubes!  It seems $400 to over $1K for a pair is not unusual.  Therefore, leaving the DAC powered up for best sound, as supported by LTA, would be a much more expensive proposition if using NOS tubes.

Can you elaborate on the specific sonic attributes, as well as the relative degree of improvement - i.e., subtle to significant, that you heard when using NOS 6SN7 tubes?  Do you believe 6SN7s in general may sound better than 12SN7s in this DAC?  Thanks for any additional thoughts you can share regarding the impact of the tubes used.

Good to hear, on all accounts.  Thanks Teajay.

I had the Aqua La Scala II DAC (not Optologic) in my system for a while some years ago and eventually sent it back. There was nothing specific that I didn’t like about it and I believe my comparison was with the Metrum Pavane, which I kept. I sort of remember at the time that I didn’t want something with tubes in it.  Unfortunately, I was not able to compare it directly against any of my Mojo Audio DACs.  I had forgotten the La Scala used four PCM1704 DAC chips, but they apparently changed that to their current proprietary Optologic D/A conversion system using FPGAs.  I may think about trying the the La Scala again instead of the LTA Aero.

My comment about the wait was based on my conversation with the owner, Mr. Mark Schneider a little over a week ago. I went ahead and placed my order as soon as we finished our discussion that day. The confirmation email indicated:

"Lead time for new LTA orders is typically about four weeks, which includes a full week of burn-in and play-testing."

Michael Lavorgna reviewed the LAIV Harmony DAC on his Twittering Machines website.  He said good things about the Harmony DAC in his review, and particularly for the price.  He happened to have the LTA Aero DAC in his Barn for review at the same time (review pending) and said this about the comparison...

"...the LTA Aero DAC ($3950) also sounded comparatively richer, fuller, and to my ears and tastes more involving, making music feel more life-like and less processed."

@teajay - Have you heard the Merason DAC 1 MkI or MkII? If yes, any thoughts compared to the (half the price) LTA Aero?

Michael Lavorgna currently has the LTA Aero DAC in his Barn for review (pending) and has also reviewed the Merason, so I also look forward to any comparisons he chooses to make.

I appreciate the effort by LTA to burn in the Aero unit at the factory and then verify it performs as advertised/expected.  I believe this is important for a company offering a 14-day audition/return period.  We discussed that I currently own (and previously owned) other well-respected DACs and that the Aero will have to bring something special to the table if I am to keep it.  Therefore, it will be powered up the entire time I have it and I think it is great that LTA are giving it at least an additional week of burn-in.

Regarding Twittering Machines, if you read the reviews, Lavorgna keeps review  gear for an extended period of time so I am confident he understands burn-in and gives the electronics plenty of time to reach their optimal performance.  I find most of his opinions to be believable and without excessive hype.  Therefore, if he chooses to make comparisons regarding the performance of the LTA Aero vs. the Merason DAC 1 MkII, I will pay attention to what he reports.

Twittering Machines’ review of the LTA Aero DAC is positive and discusses similar strengths as in the review by @teajay . Apparently Part 2 is yet to come.

The review does not include any comparisons with the previously reviewed Mearson DAC1 MkII.  Both DACs received the TM Favorite Digital recognition.

Another possible reason why he didn’t compare the Merason DAC1 MkII directly with the Aero could be that they were not both in his barn at the same time.

It seems Lavorgna likes the Liav Harmony DAC at its price point but he personally doesn’t care for its NOS mode, which he found boring, while he noted an etched or fatiguing quality when playing it in OS mode, but only in comparison to the more expensive LTA Aero DAC.

The LTA Aero seems more aligned with his sonic tastes, like his Totaldac d-1 unity reference, and wins within its weight class and above, but shows some shortcomings against the 3x more expensive Totaldac. Compared to the Harmony, he found that the Aero sounded "comparatively richer, fuller, and...more involving, making music feel more life-like and less processed." I will be interested to read what he has to say in Part 2 of the Aero review.

To understand his thoughts about the Aero vs. the Merason, it may be necessary to read about how he compared each to his Totaldac, which would put the Merason ahead of the Aero.

The LTA Aero arrived today.  Unfortunately, the Merason DAC 1 MkII has been held up in customs only two hours from me for a week now.

The LTA Aero was extremely well-packaged and super easy to set up.  It sounds good right out of the gate.  Very musical and in no way irritating.  I will give it some time before making more specific observations.

Thanks for the heads up @wig 

The LTA Aero has been burning in for a couple of days and, after a frustrating week of dealing with customs, the Merason is scheduled to be delivered this afternoon.  By running the USB output from my Sonore Signature Rendu SE Optical into a Singxer DDC, I have a variety of outputs I can simultaneously use from the DDC to feed the DACs I am comparing, so it will be easy to try the Merason with AES/EBU.

@teajay  - Thanks for bringing the Linear Tube Audio Aero DAC to our attention.  I have just started the process of comparing five different DACs I have here in the $4K to $10K price range, with the Aero being the least expensive.  I am also using a lower priced Benchmark DAC3 HGC to calibrate the others against a DAC that was designed around measuring well.  My goal is not to select a "best" but rather to compare traits and narrow the field to two or three that I enjoy most, as well as  figuring out which sonic traits are most desirable to me.  All five of them clearly sound different, even though two of them are from the same manufacturer.  Another observation I can share now is that, however this shakes out, you are absolutely correct about the LTA Aero performing well above its price range.