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Reviewer:
Srajan Ebaen
Financial Interests: click here
Source:
27" iMac (3.4GHz quad-core IntelCore i7, 16GB 1.333MHz RAM, 2TB hard disc, 256GB SSD drive, ADM Radeon HD 6970M with 2GB of GDDR5 memory); PureMusic 1.87; Amarra 2.3; Audirvana Plus 1.3.1; April Music Eximus DP1; Antelope Audio Zodiac Gold & Voltikus; Weiss DAC2; Esoteric/APL Hifi UX1/NWO-M; Audiophilleo 2; April Music Stello U3
Preamp/Integrated: ModWright LS-100 with Psvane CV-181T tubes, Esoteric C-03, Bent Audio Tap-X
Amplifier
: First Watt SIT2, ModWright KWA 100SE
Speakers: Voxativ Ampeggio, Audiomanufacture Boenicke B10, Aries Cerat Gladius
Cables: Complete loom of Zu Audio Event, Entreq & Ocellia USB cables, Stereo
lab
Tombo Trøn BNC/BNC coax
Stands: 2 x ASI HeartSong 3-tier, 2 x ASI HeartSong amp stand
Powerline conditioning: 1 x GigaWatt PF2, 1 x Furutech RTP-6
Sundry accessories: Extensive use of Acoustic System Resonators, noise filters and phase inverters
Room size: 5m x 11.5m W x D, 2.6m ceiling with exposed wooden cross beams every 60cm, plaster over brick walls, suspended wood floor with Tatami-type throw rugs. The listening space opens into the second storey via a staircase and the kitchen/dining room are behind the main listening chair. The latter is thus positioned in the middle of this open floor plan without the usual nearby back wall.
Review Component Retail: starting at €6.500

If money was no object, what DAC would I be curious about? That was my friend Dan. Mulling this potentially loaded question over for a few days, I eventually came up with two ambitiously priced contenders - CH Precision's C1 and Light Harmonic's DaVinci. Even though Dan's phrasing had removed all search parameter limitations, my criterion wasn't price. My criterion was the—presumed— potential to eclipse in any meaningful ways what Dan and I were already familiar with. That joint list would include APL Hifi, Audio Aero, dCS, EMM Labs, Esoteric, Meitner, Weiss and Zanden.


During my review of Meitner's MA-1 DAC, I brought it over to Dan who had owned Ed's previous separates. His above system comprises Alex Peychev's very best and latest transport/DAC combo, Kondo's M77 preamp, Trafomatic Audio's Vilobha monos and Aries Cerat's Gladius speakers in burgundy lacquer.


The surprise star of that session turned out to be a TotalDAC D1 Reference which Dan had ordered from France on 10-day home trial. Its stunning performance suggested a rather significant upgrade over the A1 version which Joël Chevassus had formally reviewed and which I'd subsequently heard as well.


100 nude 0.01% Vishay PG foil resistors per channel replace the usual integrated chips for D/A conversion and eliminate the need for I/V conversion. A custom IR filter compensates for the usual sin(x)/x -3dB loss at 20kHz which non-oversampling converters suffer.

I subsequently asked Dan to borrow his D1 for a weekend which he kindly allowed. Between that original session and my short-term follow-up in Villeneuve, I'd met with Nagra's Matthieu Latour and his new technical designer. Out of the blue the latter asked me what I thought of "Vincent's DAC". It took me a moment to make the connection. He knew Vincent Brient well. What's more, this engineer—he had joined Nagra since the company's restructuring under its new ownership which remains within the Kudelski family—fully concurred with Vincent's discrete R2R concept. Synchronicity?


Vincent Brient: "For USB I am using the XMOS chip but its performance depends very much on implementation. The XMOS reference board for example doesn't sound at all like what's in the D1. This is a USB Audio 2 solution and as such limited to 24/192 data. Attenuation is digital. It's performed inside the FPGA with my custom 69-bit DSP to be a proprietary solution. The RCAs output 3.3Vrms max, the XLRs twice that. About DSD over USB which you had asked about, as an R2R ladder DAC my machine will only play PCM. DSD would first have to get converted to 24/176 PCM by a software player like Audirvana which does that in real time on the fly. If you borrow Dan's DAC please select in the menu normal phase for the RCA outputs and inverted phase for the XLRs. Those are the best sounding configurations. They have since become the default settings. The enclosure paint will shortly be improved with lacquer by the way.


"Via the included remote, you can select the digital filter, grounding scheme and desired input from the configuration menu. When USB isn't activated, it's actually internally disconnected. A computer then won't see it as selectable input until USB has been turned on. For our kits I used to offer a motorized Shallco switch for remote-controlled analog volume but since we introduced our digital volume solution, nobody has asked for it. Hence that option is no longer available."


Having picked up my loaner while Dan was away, I'd promptly forgotten the remote. With his D1 last set to its coaxial input and full 00dB output, I simply defaulted to my Audiophilleo 2 for USB even though Vincent advised that his direct input would be superior. To have an even base line for my informal A/B, I used the Audiophilleo also on my customary Eximus DP1. That otherwise runs an XMOS chip on its own USB input.


Audiophilleo 2 USB-to-S/PDIF converter powered from USB's 5VDC


Since the brevity of this encounter and my inability to access all the DAC's features via remote didn't make for formal review conditions, the same brevity would apply to my sonic observations.


The arrow marks the D1 Reference power supply

Disregarding its modest sheet-metal enclosure which isn't yet up to par with price or sonic ambitions, this 'reference' converter from the DIY French underground did the same things it had done at Dan's place. First off it performed in a higher league than either the Eximus DP1 or Meitner MA-1. While I'd always suspected life beyond their class, I'd not known how much that privilege would cost. At €8.500 for this 'dual' (balanced) DAC with high-grade USB, I was still well below the CH Precision and Light Harmonic units I'd mentioned to Dan as theoretical candidates.


Performing in a higher league meant demonstrable superiority, not the type of mere flavor or gestalt shifts which had characterized my juxtaposition of DP1 and MA1 in the latter's review. Those differences had been more akin to triode vs. pentode flavors or FirstWatt's F5 vs. J2. Then two presentations show distinctive markings but are otherwise of equal stature or class. I'd secretly grown a bit tired of essentially more-of-the-same DAC reviews. I'd wondered what it would take to break higher ground that'd really be new to me. At the time I'd heard it, Vincent's A1 hadn't been it. Whilst very good particularly given its sticker, it hadn't transcended my status quo. The D1 Reference now squarely did similarly to how the Nelson Pass SIT-2 transcends his F5/J2 precedents. How so?


Presence. That was the foremost primary sensation. The D1's in-room presence was noticeably more acute, palpable and tactile. My subjective impression was that I had moved far closer to the microphone diaphragms to eliminate intermediate buffers, filters, veils and detour resistances. Secondary contributors to this more potent presence were greater dynamics; more outside-of-speaker projection on counter-phase trickery [Sevara Nazarkhan's Sen mastered by the late great Hector Zazou]; and more strongly developed tone colors. A writer needing paragraphs could spin out from here without adding essentials. It all would flow back and pool into significantly heightened presence. That was my instinctual and first gut response. Does that really require fancier explanations as to why?


On intricately percussive material I also noted unusually fine transient acuity. Scrapes, rattles, clacks and related noises had that minor shock value or charge which can't be faked. When it's there to a degree which has you involuntarily turn or twitch as though something real had just happened right next to you, the quality which audio discourse calls timing fidelity is in good order. With its ability to process 24/192 material over USB, Vincent Brien's non-oversampling DAC is decidely modern. I played native 24/192 files. I played 24/352.8kHz DXD downsampled by Audirvana 1.3.1 to 24/192. I played 24/176.4kHz DSD files converted to PCM by the same Audirvana software player. The OLED display confirmed incoming sample rates and automatic changes were accompanied by a relay click. Whilst I couldn't run the deck amp-direct without the remote, eliminating the mighty Kondo M77 in Dan's system had shocked us both when it didn't undermine the performance in any decisive ways. If as Vincent alleged performance would get even better with his own USB input—a very reasonable claim—I was beginning to sense glee coming on.


If money was no object, what DAC would I be curious about? I'd now answer Dan's intriguing question with "the fully balanced D1 Reference from TotalDAC". Except curiosity has given way to conviction. The degree to which it bested what I knew was unexpected. While I deem such a delta of performance mandatory for anything asking €20.000, my inner cynic isn't convinced such monies need to be spent. Perhaps I get to listen to a CH Precision or Light Harmonic type converter one of these days. Any excitement then would require another major performance leap beyond the D1 Reference. My cynic doubts such a dominant majority vote will happen. For now that would make this TotalDAC the still somewhat sane king of my own little hill. Brilliantly inspired pick, Dan. When did you say you needed it back?

TotalDAC website
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