The Esoteric D-02 Dual Mono D/A Converter
Digital Inputs: Asynchronous USB Audio Class 2.0: Up to16- 24bit, 32-192 kHz. RCA Digital Inputs Up to 16-24bit, 32-192 kHz. Optical 16-24 bit 32-192 kHz, XLR (Dual AES Format) 16-24bit 32-384.8 kHz. A single XLR connections supports 16-24 bit 32-192 kHz. i.Link 16-24 bit 32-192 kHz and DSD
Clock Input: BNC X2 connector
Clock Output: BNC X1 connector
Output: 2 Channel Pair of RCA single end and XLR balanced.
Dimensions (H x W x D): 6 3/8 inches X 17 1/4 inches X 13 1/4 inches
Weight: 60 pounds
Over the years, I have owned several Esoteric SACD players. I have always been impressed with the exceptional build quality and massive VRDS disc drives. The D-02 Dual Mono D/A Converter, second from the top in the Esoteric lineup, has an accompanying P-02 SACD transport with the VRDS-NEO drive mechanism. Being a computer audiophile, I have moved away from disc drives and have embraced a computer transport. Certainly, there are plusses and minuses to each type of transport, but for me, the ability to access my very large library with a remote control is essential. Esoteric has not been evading the use of computer transports, but does offer an Asynchronous USB Class 2.0 input for the D-02 DAC.
Most of us think of Esoteric as a Japanese company. In 2013 Gibson Guitar Corporation, headquartered in Nashville, purchased a controlling interest in Japan’s Teac Corporation that included the Esoteric Division and professional Tascam Division. Gibson owns a significant minority stake in the Onkyo Corporation and a majority interest in Onkyo’s American subsidiary. The Esoteric products that include amplifiers and preamps, are designed and built in Japan. Esoteric also builds loudspeakers with the final acoustic tuning, manufacturing, and assembly performed in the UK by Tannoy Ltd.
The Esoteric D-02 is physically a massive 60 pound DAC that is as large and heavy as many high end amplifiers. The D-02 is beautifully crafted in its substantial aluminum exterior. I must say that the images offered in this review fail to do it justice. The bottom chassis is made of 5mm-thick steel. Esoteric uses 4 special feet that have been patented. Esoteric claims that this four-point system suppresses vibration and reduces resonance with its high-rigidity design. I have no doubt that owners of the D-02 will experience considerable pride-of-ownership.
The interior of the chassis has a 2 deck design which is partitioned into 5 sections. Each circuit block is housed in a dedicated compartment and placed three-dimensionally in order to minimize interference between circuits and utilize the shortest signal paths.
Esoteric describes the D-02 as a 35-bit processing dual monaural digital to analog converter:
“The D-02's D/A converter ICs incorporate top-end 32-bit AK4399 chipsets by ASAHI KASEI Microdevices Corporation. Eight circuits per channel are provided to achieve phenomenal linearity and low noise. In addition to direct processing of DSD signals, the D-02 has a newly adopted “35-bit D/A processing" algorithm that converts PCM signals to analog signals at a high resolution of 35 bits.”
The D-02 has separate analog audio boards for each channel. The power supplies and transformers are also separate for each channel resulting in a true dual-monaural design. Discrete Class A buffer amplifiers are used with four circuits per channel. The front panel allows selection of a “double-parallel fully balanced buffer amp” with the XLR outputs and a “quadruple-parallel unbalanced buffer amp” with the RCA outputs.
The D-02 has 4 selectable filters, X2 and X4 up-conversion, as well as PCM to DSD64 conversion. Four selectable filters are available for PCM processing as well as a digital filter OFF mode. Two Finite Impulse Response (FIR) digital filers and two short-delay digital filters are offered. Esoteric states that the short-delay digital filters eliminate pre-echo effects in the impulse waveform to produce a more natural sounding audio signal. The FIR1 filter cut-off frequency changes according to the input sampling frequency. The FIR2 filter cut-off frequency stays at about 80 kHz regardless of the input sampling frequency. The S_DLY1 (Short Delay) filter changes according to the input sampling frequency. The S_DLY2 filter cut-off frequency stays about 80 kHz regardless of the input sampling frequency.
A 32 bit digital volume control is included that allows one to directly connect the D-02 to power amplifiers. Esoteric quotes that this system allows for a full 28 bits of audio processing when the DAC is attenuating 60 db. I found this specification to be very impressive for a built-in digital volume attenuator.
The D-02 features an Asynchronous High Speed input that supports up to 192 kHz. The Asynchronous USB High Speed drivers support both 32 and 64 bit Windows. Drivers are not only provided for Windows, but also for OSX to support up to a 192 kHz sampling rate. If the drivers are not installed, the sampling rate will only support up to 96 kHz in Windows and OSX.
The Front Panel
The front panel selection buttons are easy to use with the display and really don’t need much explanation. Let’s just say that this DAC is highly configurable, so I will just mention several of the important settings available. One must pay particular attention to the USB setting. The NOR setting is used when no driver is installed and supports up to 96 kHz. The HS_1 connects at USB high-speed mode. The HS_2 connects at USB high-speed Asynchronous mode. Naturally, this is the preferred USB mode and requires the installation of the drivers. Be sure to set the D-02 to this mode before loading the appropriate driver or you will only get up to 96 kHz sample frequency support.
The D-02 must be set to one of 3 analog output settings you are using. RCA, XLR2 where the #2 pin is HOT, and XLR3 where the #3 pin is HOT.
The XLR output settings also allow one to select the gain available. The 0dB sets the XLR output level at the same level as the RCA output. The +6dB setting sets the XLR level at double the standard RCA level.
I had no problems with installation of the High Speed USB drivers supplied for OSX Mavericks and Windows 8.1 Pro 64 bit as long as the appropriate front panel USB setting of HS_2 was selected prior to installation. I used the latest versions of Pure Music, Audiravna Plus, and J River Media Center 19 for OSX during this evaluation. I did find that the D-02 supported native Integer playback for OSX. I also listened to J River Media Center 19 for Windows with no issues.
I found that the selection of USB cables could further tweak the sound in a positive direction. I had very good results using the Audioquest Diamond. The best match for my system was with the new Synergistic Research Galileo LE USB cable. The D-02 and the Galileo LE worked flawlessly and the Galileo LE seemed to bring out the best sonic performance from this Esoteric DAC.
Given the attention Esoteric has applied to the balanced output stages, the D-02 sounded best run with balanced outputs to my Ayre MX-R amps and also when paired to my KX-R preamp. The single end RCA outputs did sound very good, but the balanced outputs sounded even better with my Ayre components that are optimized for balanced connections.
On hand for DAC comparisons were the Wavelength Audio Crimson / Denominator Silver DAC and the MSB Technology Analog DAC with the Analog Power Base.
The best way to describe the sonic presentation of the D-02 is that it is a very revealing detailed DAC. The D-02 digs down to allow one to hear the finest of details and subtle dynamic changes. The D-02 is an extremely quiet DAC with the deepest of black backgrounds I have yet experienced. Bass control is superb with a tight, tuneful presentation that can be felt as well as heard. The soundstage of the D-02 is very large and revealing. Not only wide, but front to back depth is very apparent with high quality source material. The voicing chosen for the D-02 by Esoteric is a clean sound without extra midrange fullness. The D-02 will probably not appeal to those that prefer a warmer or richer sound to their DACS. This is not to say that the D-02 is hard sounding or irritating with long listening sessions. The DAC has its own particular ease without high end accentuation.
As I listened to Michael Stern and the Kansas City Symphony (Reference Recordings HRx 24/176.4) I felt that I was hearing subtle detail I had never heard before. The D-02 allows one to hear into the score in a way that few DACs can deliver. The D-02 resolves low level information with a concurrent ultra-quiet background. I felt that the orchestral inner detail and instrumental resolution were very well reproduced with excellent recreation of the acoustics of the recording venue.
The harpsichord’s exceptional clarity of sound quality lends itself well to the contrapuntal music of J. S. Bach in The Dunedin Consort’s recording of the Six Bach Brandenburg Concertos (Linn Records 24/192). The incisive sound quality of the plucked metal strings stood out on the D-02 with transient quickness and impact. The D-02 successfully reproduced the interplay of the harpsichord with the other instruments with lifelike timbres and absolutely no image smearing.
At times, I wanted to return to the more laid-back presentation of DACs like the MSB Technology Analog DAC, but in doing so, I lost some of the instrumental textures heard with the D-02.
Dynamic Qualities Revealed
The D-02 was able to deal very well with the reproduction of the piano, especially when combined with other instruments in a jazz setting. Listening to the wonderful recording Introducing Marilay Pacheco (HiGHResAudio 24/96) the dynamic qualities of the piano were beautifully reproduced against the trumpet and percussion instruments. The color of Cuban music combined with a contemporary jazz flavor was successfully portrayed by the D-02 as it reproduced micro dynamic nuances of the piano combined with a terrific rhythmic drive. The percussion on this recording was very life-like, no doubt, aided by the transient speed of the D-02.
Engaging Musical Qualities
The D-02 is also able to draw one into the music of distinctive musicians like Natalie Merchant. Natalie Merchant’s new self-titled release (HDtracks 24/88.2) was very enjoyable when listened with the D-02. The clarity and focus of Merchant’s voice was beautifully reproduced with a supporting combination of acoustic and electric instruments. I found I was able to simply enjoy the lyrics and music without worrying about the sound quality. The D-02 allowed this recording to come across with a relaxed presentation that was very engaging.
The D-02 Volume Control
The high precision digital volume attenuator found on the D-02 was used with the balanced XLR outputs. The additional ability to select two output levels helped to make this control very versatile in level matching with my Ayre amps and Wilson speakers. The 32 bit digital volume attenuator was compared to my Ayre KX-R preamp. The amps used were the Ayre MX-R monoblocks.
I found that direct connection of the D-02 to the Ayre MX-Rs had a high level of sound quality with no noticeable degradation of the sound. I was very impressed with Esoteric’s implementation of this control which resulted in sound quality very close to the overall quality of that heard with the Ayre KX-R. The KX-R did have a more relaxed, rounded sound that I felt helped the D-02 with its highly detailed presentation. Ayre has released a new KX-R Twenty preamp that claims to have significant improvements in performance over the KX-R. I have signed up for the update of my KX-R and hope to hear from Ayre soon.
I do have one significant complaint concerning the D-02 and its volume control. For some reason unknown to me, Esoteric has decided not to include a remote control with this DAC. Given the rather high price of this DAC and its many selectable settings, the absence of a remote control just doesn’t make sense to me.
Digital Filter Settings, Upconversion, and DSD conversion
I did find that the FIR2 filter added a bit of richness to the sound in my system. I also found that the filters made a small but perceptible change to the sound; the preference varied with source material. The 2Fs and 4Fs upconversion settings were tried with 16/44.1 files. A slightly bigger soundstage resulted with a bit of smoothing of the high end response and a slightly fuller low end.
What actually impressed me the most with the D-02 was the conversion of PCM to DSD64. While some of the ultimate focus and inner detail were lost, the sound had more bloom and a greater sense of ease. The soundstage was also larger sounding with the DSD setting.
But as with the volume attenuator, the lack of a remote control was sorely missed for sonic comparisons of filters, upconversion, and DSD conversion.
The DAC that comes to mind after having performed extended listening to the Esoteric D-02 is the Empirical Audio Overdrive SE USB DAC / Pre. Both DACs are extremely detailed and fast sounding without a euphonic addition of richness to the overall sound. The far more expensive Esoteric D-02 is bigger sounding with even more dynamic impact than I remember with the Overdrive SE. The transient quickness and impact of the D-02 also surpasses what I remember the Overdrive SE possessing.
The MSB Technology Analog DAC with Analog Power Base, and for that matter, the Wavelength Audio Crimson / Denominator with Silver transformers, represents a very different sonic philosophy compared to the D-02. The sound of the Analog DAC is more laid-back with a less up front presentation than that heard with the D-02. The Wavelength DAC, while being very detailed with its Silver transformers, has its own particular sound with a greater sense of overall bloom most likely the result of the 71A directly heated triode output tubes. The D-02 sounds more impactful and faster than the Wavelength or the Analog DAC. But the Wavelength brings enhanced spatial resolution and midrange harmonic richness to its sonic presentation.
Among The Best
The Esoteric D-02 must be included with the finest DACs I have had the opportunity to evaluate over the last 2 years. The D-02’s engineering and build quality takes a back seat to no one. The D-02’s remarkable ability to reveal low level information and its superb dynamic qualities make it a formidable competitor amongst other state-of-the art DACs. The voicing that Esoteric has chosen for the D-02 will not appeal to all listeners, but when carefully matched with complimentary components, the lucky audiophile will undoubtedly have a memorable musical experience.