Digital Processors
Editor's Note: The sound of any particular CD transport/digital processor combination will be dependent on the datalink used-see "Bits is Bits?" by Christopher Dunn and Malcolm Omar Hawksford, Stereophile, March 1996, Vol. 19 No.3 (WWW). Unless mentioned, processors are limited to 32/44.1/48kHz sample rates. To be included in Class A+, a digital processor must be capable of handling DSD or 24/96 LPCM data.
We strongly recommend those interested in using a computer as a true high-end digital audio source visit our sister website www.AudioStream.com, which is edited by Rafe Arnott.
A+
Ayre Acoustics QX-5 Twenty: $9950
Ayre may not be the only consumer-audio manufacturer whose digital processors have found success in pro-audio settings, but their QX-R Twenty—a DAC whose 100-step digital-domain volume control and 11-strong phalanx of digital inputs make it suitable for use as the hub of an all-digital domestic system—distinguished itself by creating the analog master for the LP version of Stereophile's most recent commercial recording project (Sasha Matson's Tight Lines). The Ethernet-friendly, Roon-Ready QX-5 Twenty has at its core ESS's new ES9038PRO chip, supplemented with proprietary Ayre filters running on a Xilinx FPGA chip. Used in his own domestic system, the Ayre at first impressed JA with its "[D]etail. And more detail," and although the Ayre never overstepped its bounds in that respect, the combination of QX-5 Twenty plus MBL Corona C15 amps and Rockport Avior II speakers "resulted in a slightly relentless quality," compelling him to play music "at a lower level than I'd been used to." Adding to his system the Ayre KX-5 Twenty preamp and disabling the Ayre DAC's digital volume control ameliorated the forwardness, and contributed to JA's conclusion that "feeding audio data over my network to the QX-5 with Roon . . . rather than USB connections, is the way forward." Writing from his fortress of testitude, JA declared that "Ayre's QX-R Twenty digital hub offers superb measured performance." (Vol.40 No.9 WWW)
Benchmark Media Systems DAC3 HGC: $2199
Benchmark's DAC3 HGC—the last three letters designate this as the audiophile version, with a headphone amp and two analog inputs—supports files up to 24/192 and DSD64, the latter as DoP (via USB). Bearing in mind the manufacturer's suggestion that there should be no audible difference between their DAC1 and DAC3, JCA wrote, "In fact, I found the sounds of the two DACs quite different. The DAC1 was brighter . . . the DAC3 was all about depths, in several respects . . . I heard deeper into the music." The concise conclusion to JA's Measurements sidebar: "All I can say is 'Wow!'" In a Follow-Up, JCA wrote of using the Benchmark processor with the same company's AHB2 power amp—a combination of high source output voltage and modest amplifier gain that he describes as "optimal for minimizing noise and distortion"—and reported hearing "richer and more interesting" reproduction of very subtle details. (Vol.40 No.11, Vol.41 No.10 WWW) Chord Electronics DAVE: $10,900
The DAVE—an acronym for Digital to Analog Veritas in Extremis—derives from the work of Chord designer Rob Watts, whose Watts Transient Aligned (WTA) filter is claimed to eliminate the timing uncertainty associated with conventional DACs of comparatively limited processing power. And the DAVE's processing power is prodigious: As JA explains, "Watts ended up with a 17th-order noise shaper (!) with 350dB dynamic range (!!) in the audioband, equivalent to 50 bits resolution (!!!)." In his system, the DAVE, which is compatible with PCM up to 32 bits/768kHz and DSD up to DSD512, sounded so good that it tore editor JA away from editing: "Darned if I didn't have to go sit in the listening chair, so compelling was the sound produced by the DAVE." In particular, he praised the DAVE's "superb re-creation of soundstage depth, its sense of musical drive, and the clarity with which it presented recorded detail." Reporting from his test bench, JA wrote: "Even if I hadn't auditioned Chord's DAVE, I would have been impressed by this DAC. Its measured performance is beyond reproach." (Vol.40 No.6 WWW) Chord Hugo M Scaler: $4795
The Chord Hugo M Scaler is a digital processor but not a digital-to-analog processor, its purpose being the upsampling—referred to in the UK as upscaling—of incoming data. When connected to a Chord DAC via BNC connectors, the M Scaler can upsample up to 705.6kHz or 768kHz, but with non-Chord DACs the upper limits become 176.4kHz and 192kHz. (In all cases, incoming DSD data is converted to PCM, with a 6dB reduction in level.) JA used the M Scaler with Chord's DAVE D/A processor, and with his own PS Audio and Mark Levinson DACs. In all cases, but especially with the DAVE, upsampling via the M Scaler offered such improvements as "more image depth, an increased sense of drive, and even more clarity." That said, owing to the fact that the M Scaler is "relatively expensive," JA recommends auditioning it with your DAC of choice "before getting out the credit card." (Vol.43 No.3 WWW)
dCS Bartok w/headphone amp: $16,250
w/o headphone amp: $13,500
The "perfectly" named dCS Bartók—judged so by JCA for its modernist, single-box sensibility—brings an unprecedented level of thrift to the company's offerings: It is both the company's most affordable D/A processor and the one that offers the highest level of per-chassis functionality, owing to its inclusion of a headphone amplifier (which can be omitted for a $2750 savings) and an onboard version of the dCS Network Bridge streamer, the latter allowing playback from streaming services, network storage devices, and USB-connected flash drives. At the heart of the Bartók remains the manufacturer's patented Ring DAC technology, here supporting native sampling rates up to 24-bit, 384kHz and up to DSD128. According the JCA, the Bartók "consistently and unambiguously revealed the character of the recordings it played, with clarity, pinpoint imaging [and] excellent image depth, fully saturated tonal colors, and no noticeable emphasis on any part of the frequency spectrum." Although neither writer saw the other's work until press time, Jim's conclusion—"the state of the art"—was echoed by JA in his test-bench report: "In this crusty old engineer's view, 'dCS' means 'Digital Done Right!' (Vol.42 No.10 WWW) dCS Network Bridge: $4750
Designed for use both with the company's top-of-the-line Vivaldi DAC and other DACs, the dCS Network Bridge is a Roon-ready, one-box network player that can serve as a bridge between the user's NAS (or other such file source) and DAC, and can also stream content from Tidal, Spotify, and other services. Ethernet, AirPlay, and USB inputs are offered, as well as BNC inputs for an external clock; outputs are a pair of dCS-compatible AES/EBU XLR sockets and a single S/PDIF RCA jack. Supported formats are PCM to 24/384 and up to double DSD, either native or DoP. (WiFi performance is limited to 24/96.) JVS found that even before the Network Bridge was fully warmed up, it delivered "instrumental textures [that] were far more palpable than before," compared to his own dCS Rossini DAC/player. After extended listening, JVS declared that the dCS's sound was "demonstrably superior to conventional computer-audio playback via USB," and described the Network Bridge as "an invaluable—I'd say indispensable—asset for owners of a Vivaldi or older dCS DAC." (Vol.40 No.12 WWW) dCS Rossini DAC: $23,999
Were you to discard or disable the disc transport in your dCS Rossini Player, you would essentially have a Rossini D/A processor—which, like the Rossini Player, upsamples to PCM 352.8kHz or 384kHz and supports both DoP and native DSD up to DSD128. That said, if you wish to use the Rossini DAC to enjoy SACDs, you'll need a separate dCS transport, such as the dCS Vivaldi ($41,999). In the January 2017 Stereophile, JVS described using the Rossini DAC in place of his dCS Puccini player: "The Rossini seemed to dive into the center of the music and bring it home in ways the Puccini could not." In the May 2018 Stereophile, Jason reported on using a Rossini DAC that had been upgraded with full MQA compatibility: "The improved sound the Rossini drew from [my] MQA tracks was easily audible, and took recorded sound to another level, viscerally and emotionally." In the June 2019 issue, JVS reported on dCS's Rossini software v2.0, which applies to both this product and the Rossini Player. (Vol.40 No.1, Vol.41 No.5, Vol.42 No.5, Vol.42 No.6 WWW)
EMM Labs DV2: $30,000
EMM Labs' newest product is the first D/A processor to make use of the company's new VControl, a high-resolution volume-control system. Of its seven digital inputs, the DV2's USB Type B input is its most versatile, enabling PCM conversion up to DXD, DSD up to DSD128, and full MQA unfolding. Also provided are two coaxial (RCA) S/PDIF inputs, two optical (TosLink) S/PDIF inputs, one AES/EBU (XLR) input, and one proprietary EMM Optilink for SACD and CD playback. In his listening tests, JVS tried using the DV2 in a variety of configuration; he noted that, by the time he'd done so, "it had become clear that the DV2 is one of the finest-sounding DACs with volume control that I've ever heard in my reference system." Indeed, Jason praised the DV2 for delivering, compared to other processors he's enjoyed in that setting, "the smoothest, most naturally warm, most consistently engaging and non-fatiguing reproduction of music." Writing from his test bench, JA noted that the DV2 offers resolution that's "close to the state of the art." (Vol.42 No.3 WWW) exaSound e38 MkII: $4299
The e38 was introduced in 2017 as the third-generation version of exaSound's multichannel DAC, preceded by the e18 and the e28. In 2019, exaSound introduced the e38 MkII, which replaced the ESS ES9028PRO chip of the original e38 with ESS's new ES9038PRO DAC, said to have four times as many internal paralleled DAC channels. There are also redesigned reference voltage sources and master clock power circuits as well as redesigned mainboard and output stages. Reviewing a sample of the e38 MkII equipped with balanced mini-XLR outputs—an all-single-ended-output version can be had for $3999—KR found that the MkII "was somewhat more detailed and open compared to the original." Kal's conclusion: "By today's standards, this one is pretty much beyond criticism." (Vol.40 No.7, Vol.42 No.9 WWW) Meridian Audio Ultra DAC: $23,000
The MQA-compatible Ultra DAC offers both balanced (XLR) and single-ended (RCA) outputs, virtually every kind of digital input you can imagine, and at least one you might not: a SpeakerLink connection, for use with Meridian's digital active loudspeakers. The Ultra DAC boasts a presumably futureproof card-frame construction, with separate dual-mono DAC cards, a high-current clock card, and a first-in, first-out (FIFO) buffer card, intended to minimize jitter. The power supply is linear as opposed to switch-mode. Alongside MQA, Meridian's flagship is compatible with PCM up to 24/384, as well as DXD files and DSD64 and 128. Signal-polarity inversion and EQ are available via the DAC's menu system, and the user has a choice of Long, Medium, and Short reconstruction filters. Used with PCM files, JA's first impressions of the Ultra DAC were of "a smooth sound with superb transparency and soundstage depth," and he praised its low-frequency performance as "powerful and extended." While listening to an MQA file of pianist Robert Silverman JA noted that "the MQA recording presented the width and depth of the Steinway in an uncannily realistic manner." Taking over from JA the listener, JA the measurer praised the Meridian's low distortion and good rejection of word-clock jitter. Both JAs agreed that the Ultra DAC joins dCS's Rossini and Vivaldi DACs in offering "the best sound I have enjoyed from digital recordings." (Vol.40 Nos.5 & 6 WWW)
Mytek Manhattan DAC II: $5995
Offering MQA, DXD, DSD256, and PCM up to 32-bit/384kHz, the Mytek Manhattan II is, in HR's words, "a complete digital and analog service provider." Add Mytek's optional phono card ($1495) and it becomes a phono preamp; add its Roon-ready WiFi card ($995) and it becomes a network streamer with maximum throughput of 24/192 and DSD64. Also on tap in the base model are a discrete, high-current headphone amp, and a user-selectable choice of seven different filters for CDs and PCM files. After sampling some of his favorite MQA files through the Manhattan II, HR asked: "If you were contemplating the purchase of a new DAC, why would you not want it to include MQA processing?" As for its performance with CDs, he wrote, "the Mytek let my mind rise and then look down on the musical stream, to observe the matrix of its notes and silences." Overall, he praised the "uniquely non-digital"sounding Mytek Manhattan II for "[reproducing] recordings in a manner that seemed devoid of mechanicalness or electronic artificiality. Class A all the way." JA summed up the results of his lab tests in one short sentence: "Mytek's Manhattan II offers superb measured performance." (Vol.40 No.9 WWW) Playback Designs Sonoma Merlot: $6500
Designed and released at the same time as Playback Designs' Sonoma Syrah music server (see elsewhere in this edition of "Recommended Components"), and housed in a similar-looking enclosure 12" wide by 3.25" high by 9" deep, the Sonoma Merlot stereo DAC offers the usual USB, S/PDIF, and AES/EBU inputs, plus Playback's proprietary PLink, for connection to their USB-XIII Digital Interface ($2500), which acts as a master clock in multichannel systems. On its USB and PLink inputs, the Sonoma Merlot provides up to 24-bit/384kHz PCM resolution, and does DSD up to DSD256; the remaining inputs are limited to 24/192 and DSD64. A headphone amp with a front-panel 1/4" jack is also provided. After borrowing and using three (!) Sonoma Merlots—the extra two were required for surround sound—with the above-mentioned server and digital interface, KR praised the system's "beautiful sound." Using the Sonoma Merlot with his Baetis Prodigy X server and comparing that combo with his exaSound e38 multichannel DAC, KR found that "soundstage detail was equal" between the two, but that "the exaSound was a bit more forward," and the trio of Merlots "more naturally arrayed." (Vol.40 No.9 WWW) PS Audio PerfectWave DirectStream DAC: $5999 ★
Instead of an off-the-shelf chipset, PS Audio's first DSD processor uses original code written into a field-programmable gate array (FPGA), the result being a system that converts all incoming data to double-rate DSD. In addition to asynchronous USB, the digital inputs include RCA, TosLink, and HDMI, and single-ended and true balanced analog outputs are provided. The DirectStream is built on a cast-alloy chassis with a glossy MDF top and a touchscreen from which all user controls can be worked. Firmware is user-updatable, as AD discovered while reviewing the DirectStream. He noted the DAC's "excellent pacing, flow, correctness of pitch relationships, and the like, as well as a consistently smooth and slightly laid-back sound." With some files, AD found the DirectStream just a little too laid-back—a condition mitigated in part by an early firmware update—but found its musicality beyond reproach. JA observed that the DirectStream "measures superbly well" in many ways, but was troubled by its poor linearity at low frequencies and its "ultimate lack of resolution" with hi-rez files. In a Follow-Up, RD tried the DirectStream DAC with PS Audio's PerfectWave Memory Player transport ($3995) and observed, "listening to familiar recordings . . . I heard more musical detail from them than I previously had." Subsequent to that audition, RD received and installed in the DirectStream DAC a new firmware upgrade, bringing his unit to v.1.2.1; he liked it. Following the firmware update to v.1.2.1, JA re-tested the DirectStream DAC and found evidence of a lower noise floor, increased low-level linearity, and a dramatic reduction in low-frequency distortion. Said JA: "Kudos to PS Audio for designing a product so that its performance can so easily be upgraded by its customers." There have followed three additional, successive firmware upgrades; in 2017, the most recent of these, named Huron, impressed JCA as "a clear improvement over [its immediate predecessor], which was already very good." (Vol.37 No.9; Vol.38 Nos.2, 3, 5, 11; Vol.39 No.11; Vol.40 No.10 Vol.42 No.6 WWW)
T+A DAC8 DSD: $4450
The German-built T+A Elektroakustik DAC 8 DSD incorporates two distinct sets of D/A converters: DSD signals are treated to 1-bit conversion and are never converted to PCM, while PCM signals are treated to four DACs per channel in a double-differentiation configuration that, according to JI, is claimed to "perfectly cancel out converter errors and nonlinearities while increasing dynamic range by 6dB." Also on tap are four user-selectable digital filter options, independently adjustable volume for line and headphone outputs, and separate, user-selectable analog filters for DSD and PCM, the former intended to protect the rest of the user's system from ultrasonic noise. JI praised the DAC 8 DSD for "approach[ing] the performance of cost-no-object designs" and "represent[ing] good relative value." JA gave the DAC 8 DSC a clean bill of health, with particular regard to its "superb rejection of word-clock jitter via its PCM inputs," while noting that "its measured behavior and sound quality [are] so dependent on which of its four digital filters is in use." (Vol.39 No.10 WWW) A CanEver Audio ZeroUno: $9950
While digital processors with tubed output sections aren't new, the Italian CanEver Audio ZeroUno breaks with convention by looking less like a DAC than a 2A3-fueled power amp, its two Coke-bottlestyle CV181 dual-triode tubes enjoying pride of place atop a distinctly attractive case. Under its skin is an ESS Sabre32 ES9018S chip, its eight internal differential DACs used in a quad-sum configuration. Supplementing the ESS chip are multiple PCM and DSD filters of CanEver's own design, selectable via a menu system that also provides a switchable jitter filter, signal-polarity inversion, channel balance, and other niceties. The ZeroUno supports PCM to 384kHz and DSD64 and 128 as DoP; newer versions of the CanEver DAC are said to provide MQA compatibility, though that was not available at the time of our review. AD noted shortcomings in the ZeroUno's manual, especially when it came to navigating its software menu—we're told that this, too, has been refined in current production—but forgot those complaints after noting that the Italian DAC made his favorite files sound more colorful and "less hi-fi" than what he's used to hearing from digital playback. Art's conclusion: "I've heard no other digital product that succeeds quite so well . . . at letting music sound like music." Writing from his testing lair, JA noted the ZeroUno's "respectable measured performance," but cautioned users to keep its jitter and oversampling filters switched on. (Vol.40 No.5 WWW) Chord Electronics Qutest: $1695
JA, who regards Chord Electronics' upmarket DAVE ($12,488) as "one of the best-sounding DACs I've had in my system," jumped at the chance to review Chord's far less expensive Qutest, which draws from the same well: It's based on the company's proprietary 10-element Pulse Array Design processor, designed by Rob Watts and implemented in a Field Programmable Gate Array (FPGA) chip. Via its USB port, the compact (6.3" wide by 1.6" high by 2.85" deep) Qutest handles DSD256 (as DoP) and PCM up to 768kHz, but lacks MQA decoding. In his listening observations, JA praised the Qutest for "the excellent sense of motion" it lent to a favored piano-concerto recording, from which he also heard "stably and clearly positioned" stereo images, if not quite the soundstage depth he'd hoped for. JA the measurer uncovered, among other things, the fact that the Chord Qutest "offers almost 21 bits' worth of resolution, which is close to the state of the art." JA the reviewer concluded: "strongly recommended." In a Follow-Up, HR described his own experiences with the Chord Qutest, in which he noted that this DAC "might be doing something unusually right in the time domain." His conclusion: "a must-audition for every serious audiophile." (Vol.42 Nos. 1 & 3 WWW)
Mytek Brooklyn Bridge: $2995
In creating the Brooklyn Bridge, Mytek essentially took their Class A Brooklyn DAC+ ($2195)—a high-resolution processor that supports 32/384 PCM, DSD to DSDS256, and full MQA unfolding, and also includes a headphone amp and a line-level and phono preamp—and updated it with streaming and network server capabilities, via wireless or Ethernet connections. Qobuz, Tidal, Deezer, vTuner, and Spotify are supported. As JCA wrote, "The Brooklyn Bridge aspires to and approaches sonic neutrality. I hear a rich, detailed sound with fullness and depth but without exaggerated lows, and with a crystalline quality in the highs," and noted that, as the only streamer he's aware of "that incorporates a DAC used in studios," it is in a class by itself. (Vol.42 No.9 WWW) Mytek HiFi Brooklyn DAC+: $2195
Mytek, which has its roots in the pro-audio industry, took aim at the consumer-audio marketplace with their original Brooklyn-made Brooklyn DAC ($1995), which also functions as a line-level preamplifier, a two-output headphone amplifier, and MM/MC phono preamp. The compact (8.5" wide) Brooklyn offers 32-bit performance via USB, 384kHz PCM resolution, and can handle up to DSD 11.2896MHz as well as unfold MQA files. Selectable digital filters are offered, as are controls for volume (the user's choice of analog or digital), balance, mono, and signal-polarity (phase) inversion. JCA, who preferred the Mytek's sound with its volume control set for analog, reported having a hard time getting a handle on the Brooklyn's sound, but once he did, he heard "bass instruments reproduced fully and cleanly," a soundstage that was "deep and layered," with images "precisely positioned in space," and a sound that was, with all but the lousiest recordings, "very open." Writing from his test bench, JA praised the Brooklyn's "very low" noise, "superb" rejection of word-clock jitter, and an "excellent" signal/noise ratio—among other things—from its phono stage, concluding, "the Mytek Brooklyn's measured performance is superb . . . color me impressed." In the May 2017 Stereophile, KR described using three Mytek Brooklyns to play multichannel MQA recordings from 2L Recordings, prompting from Kal this reference to JCA's Brooklyn review: "I can echo his sentiments about its revelation of soundstage and texture." In the same issue, Brooklynite HR summed up his own experiences with the Mytek, through which he enjoyed streaming MQA-encoded Tidal Masters files: "I'm happily addicted to MQA, Tidal Masters, and the Mytek Brooklyn." In the April 2017 Stereophile, JCA reported on this product's latest incarnation, the Brooklyn DAC+ ($2195), which is built around the new ESS Sabre 9028 Pro DAC chip, and offers an improved analog attenuator circuit and other refinements. In a side-by-side comparison of the two Brooklyns, JCA heard little difference: "There may have been a slight increase in transparency in the upper midrange/lower treble with the DAC+," he said, but at the end of the day JCA got "superb [sound] from both Brooklyns." (Vol.39 No.11, Vol.40 No.5, Vol.41 No.4 WWW) Pro-Ject Pre Box S2 Digital: $399 $$$
This combination D/A processor and headphone amp measures just 4.1" square and 1.4" high and uses dual ESS Sabre Pro ES9038 chips to offer up to 32-bit/768kHz PCM and DSD up to DSD512, plus eight user-selectable PCM reconstruction filters and full unfolding of MQA files. In using the Pre Box S2 Digital to compare MQA files to their non-MQA versions, KM wrote that "the soundstage seemed to grow and surround my head," describing the Pro-Ject DAC's MQA performance as "a revelation." Ken praised the DAC's user-friendliness and concluded, "I can think of no other mini-machine that does so much so well." Writing from his test bench, JA observed very low noise—"extraordinarily good, considering that the Pre Box S2 Digital is powered by a tiny wall-wart supply. Someone at Pro-Ject knows how to optimize a printed-circuit-board layout!" In a Follow-Up report, HR wrote that the Pre Box S2 Digital "preferred sensitive, easy-to-drive headphones" such as his own AudioQuest NightHawks, judging that combination "lively, smooth, and very musical." (Vol.42 Nos.4 & 5 WWW)
Schiit Audio Yggdrasil: $2399
Is high-end audio ready for a company whose all-out statement DAC costs only $2299? Ready or not, Schiit Audio's Yggdrasil is here, offering what Schiit describes as a true "21 bits of resolution" and proprietary digital filtering, implemented on an Analog Devices processor, that retains rather than destroys "all the original samples." Also featured is a hefty regulated power-supply section built around twin transformers: one for the digital supplies, the other for analog. Input signals of resolutions up to 24-bit/192kHz are accepted. According to HR, in contrast with the "grainlessness" of the Mytek Brooklyn DAC, "the Schiit's sound was slightly textured, and dynamic contrasts were less evident." That said, Herb also observed that "the Yggdrasil exposed melodic lines . . . and human voices—also better than any DAC I've heard costing less than five grand." JA's measurements comprised a mixed report, with praise for the Schiit's "superbly well designed" analog circuitry set against his impression of "digital circuitry [that] is not fully optimized." In 2018, Schiit introduced their Analog 2 upgrade—two new output cards and a firmware update for the DSP board—available to owners of older Yggdrasils for $550. HR wrote in a Follow-Up that the upgrade, which must be performed by Schiit or by an authorized service center, allowed his Yggdrasil to sound "quieter, more refined, more transparent, more silky, more tactile." (Vol.40 No.2, Vol.41 No.9 WWW) B DSPeaker Anti-Mode X4 Preamplifier-DAC: $4250
The Anti-Mode X4 is a full-featured two-channel line-level preamplifier plus DAC with multiple inputs—single-ended and balanced analog inputs, plus USB, S/PDIF, and TosLink digital—multiple outputs, and, as KR describes it, "a head-spinning array of digital-signal-processing (DSP) tools." It also comes with a calibrated microphone and stand, for use with its many DSP functions—including room/speaker EQ for full-range speakers and for subwoofers; subwoofer level control; bass and treble tilt controls; infrasonic filtering; and a L–R balance control. A promised EQ function for four subwoofer channels has yet to materialize—but even so, KR found the Anti-Mode X4 in its present state to be useful, effective, and altogether "great just as it is." (Vol.42 No.5 WWW) iFi Audio Pro iDSD: $2749
Built around four Burr-Brown DSD DAC chips operated in what iFi calls an "interleaved" array, the Pro iDSD offers up to DSD1024 and 32-bit/768kHz PCM—and more controls and performance options than can be fully described in a review of reasonable length, let alone a little blurb like this. Suffice it to say the iFi contains a three-output, selectable-gain headphone amplifier, has built-in support for streaming from Qobuz and Tidal, performs full unfolding of MQA files, has balanced (XLR) and unbalanced (RCA) outputs, offers defeatable upsampling with a variety of user-selectable filters, and, among its many other output options, contains a user-selectable tubed output circuit. HR said of its performance on an especially beloved Sun Ra recording, "the Pro iDSD's DAC did a sterling job of sorting out the countless spatial layerings of this track," and added the iFi to his "short list of DACs that recover an enjoyable illusion of dense bodies playing music." Measuring the iFi proved to be a mammoth task—"With so many output options and operating modes, it's easy to become confused about the iFi Pro iDSD's performance," JA noted—but in the end, despite a couple of puzzling idiosyncrasies, he found "much to admire in its measured performance." (Vol.42 No.1 WWW)
Mytek Liberty: $995 $$$
More than one Stereophile scribe has sung the praises of Mytek's original Brooklyn DAC, known as much for its extras—an onboard line-level preamp with analog volume control, an MM/MC phono stage, and a two-output headphone amp—as for being a great-sounding D/A processor. Now comes the Mytek Liberty, a stripped-down model said to be the sonic equal of the original Brooklyn (which has since been replaced by the even better-performing Brooklyn DAC+: see elsewhere in "Recommended Components"). Built around a 32-bit ESS Sabre DAC chip, the Liberty offers, via its USB input, PCM performance up to 24/384 and DSD up to DSD256. Gone are the preamp, the phono stage, and one of the two headphone outputs; retained is full MQA compatibility. The Mytek Liberty impressed AD with its musical capabilities, including good senses of momentum and touch, and by sounding appropriately crisp while "never [becoming] gritty." In measuring the Liberty, JA noted resolution to almost 19 bits, which is quite good, and said that the DAC's measured performance "indicates excellent digital and analog engineering, especially considering its affordable price." Quoth AD: "Very highly recommended." (Vol.41 No.11 WWW) Prism Sound Callia: $1899
The first domestic product from UK-based pro-audio specialists Prism Sound, the Callia D/A converterheadphone amplifier is based on a dual-mono pair of Cirrus Logic CS4398 DAC chips, and accepts DSD data up to DSD128 and PCM to 384kHz, though the former is converted to PCM and the latter is downsampled to 192kHz. Its front panel is graced with two separate volume controls: one for the Callia's line outputs, the other for its front-mounted 1/4" headphone jack, further enhanced with a three-position DIP for optimizing the output for low-, medium-, and high-impedance 'phones. When JA used the Callia to drive his Audeze LCD-X headphones, he described the sound as "richer than I expected," while in his Big Rig—without a preamplifier, and with the Callia's own volume control doing the honors—the sound was "drier," with less soundstage depth than JA gets from his PS Audio PerfectWave DirectStream DAC, but no loss of power from drums and electric bass. JA praised the "excellent-sounding" Callia, but described the Mytek Brooklyn's sound as "slightly better"—and noted that the then less expensive Mytek adds MQA compatibility. Apart from some surprising jitter-related (as opposed to power-supplyrelated) sidebands, the Callia performed respectably on JA's test bench. Significant price reduction as of July 2018. (Vol.41 No.4 WWW) C Arcam irDAC-II: $749 $$$
Fresh from flings with four- and five-figure DACs, JA reconnected with the hoi polloi via Arcam's affordable irDAC-II, introduced in 2016 to celebrate the British company's 40th anniversary. Built around the ESS ES9016 K2M DAC chip, the Arcam combines five digital inputs—two RCA, two TosLink, one USB—with Bluetooth connectivity and a headphone amplifier, and supports files up to DSD128. After using an AudioQuest Cheetah interconnect to wire the irDAC-II directly to his power amps—the former has its own volume control, thus eliminating the need for a preamp—JA was impressed by the Arcam's cleanness, clarity, and definition with a variety of tracks, though he noted a shallower-than-expected soundstage with some material, and felt its balance was a little lightweight—also a characteristic of the irDAC-II's headphone output. That said, via his AudioQuest NightHawk headphones, the Arcam outperformed the Meridian Explorer DAC: with one recording in particular, the irDAC-II "opened up a somewhat cleaner, clearer view into the recorded acoustic." As for the Arcam's Bluetooth performance, JA described it as "always listenable, if not completely involving." Writing from his lab, JA praised the irDAC-II as "a conventional but well-engineered D/A processor." (Vol.40 No.7 WWW)
BorderPatrol Digital to Analogue Converter SE: $995–$1850
In BorderPatrol's Digital to Analogue Converter SE the processor of choice is the same Philips TDA1543 16-bit chip found in playback gear from the 1980s and '90s, implemented without a digital reconstruction filter, energized by analog power supply with twin mains transformers and a tube rectifier. It has two inputs—USB and S/PDIF—and is built with a copper chassis, upgraded signal and power-supply capacitors; non-SE versions with a single input, more modest caps, and no rectifier tube are also available. HR wrote that the DAC SE "delivers refined, human-sounding musical pleasures—at a very reasonable price." Writing from his testing lab, JA noted a severe channel imbalance with data sampled at rates higher than 96kHz, channel-specific anomalies in linearity error, a higher-than-expected noise floor, and disappointing performance in its rejection or word-clock jitter. In a Follow-Up that proved controversial, JI described comparing the Border Patrol DAC SE with his Benchmark DAC2 HGC, concluding that the BorderPatrol "purred like a sweet, sultry voice . . . even as it lied to me." (Vol.41 Nos.9 & 11 WWW) K Denefrips Ares R2R DAC. Deletions
Auralic Altair, Chord Hugo TT, HoloAudio Spring Kitsuné Tuned Edition Level 3, replaced with newer models not yet reviewed. Bryston BDA-3, Moon 780D, TotalDac d1-tube-mk2, not auditioned in a long time.
Ayre may not be the only consumer-audio manufacturer whose digital processors have found success in pro-audio settings, but their QX-R Twenty—a DAC whose 100-step digital-domain volume control and 11-strong phalanx of digital inputs make it suitable for use as the hub of an all-digital domestic system—distinguished itself by creating the analog master for the LP version of Stereophile's most recent commercial recording project (Sasha Matson's Tight Lines). The Ethernet-friendly, Roon-Ready QX-5 Twenty has at its core ESS's new ES9038PRO chip, supplemented with proprietary Ayre filters running on a Xilinx FPGA chip. Used in his own domestic system, the Ayre at first impressed JA with its "[D]etail. And more detail," and although the Ayre never overstepped its bounds in that respect, the combination of QX-5 Twenty plus MBL Corona C15 amps and Rockport Avior II speakers "resulted in a slightly relentless quality," compelling him to play music "at a lower level than I'd been used to." Adding to his system the Ayre KX-5 Twenty preamp and disabling the Ayre DAC's digital volume control ameliorated the forwardness, and contributed to JA's conclusion that "feeding audio data over my network to the QX-5 with Roon . . . rather than USB connections, is the way forward." Writing from his fortress of testitude, JA declared that "Ayre's QX-R Twenty digital hub offers superb measured performance." (Vol.40 No.9 WWW)
Benchmark's DAC3 HGC—the last three letters designate this as the audiophile version, with a headphone amp and two analog inputs—supports files up to 24/192 and DSD64, the latter as DoP (via USB). Bearing in mind the manufacturer's suggestion that there should be no audible difference between their DAC1 and DAC3, JCA wrote, "In fact, I found the sounds of the two DACs quite different. The DAC1 was brighter . . . the DAC3 was all about depths, in several respects . . . I heard deeper into the music." The concise conclusion to JA's Measurements sidebar: "All I can say is 'Wow!'" In a Follow-Up, JCA wrote of using the Benchmark processor with the same company's AHB2 power amp—a combination of high source output voltage and modest amplifier gain that he describes as "optimal for minimizing noise and distortion"—and reported hearing "richer and more interesting" reproduction of very subtle details. (Vol.40 No.11, Vol.41 No.10 WWW) Chord Electronics DAVE: $10,900
The DAVE—an acronym for Digital to Analog Veritas in Extremis—derives from the work of Chord designer Rob Watts, whose Watts Transient Aligned (WTA) filter is claimed to eliminate the timing uncertainty associated with conventional DACs of comparatively limited processing power. And the DAVE's processing power is prodigious: As JA explains, "Watts ended up with a 17th-order noise shaper (!) with 350dB dynamic range (!!) in the audioband, equivalent to 50 bits resolution (!!!)." In his system, the DAVE, which is compatible with PCM up to 32 bits/768kHz and DSD up to DSD512, sounded so good that it tore editor JA away from editing: "Darned if I didn't have to go sit in the listening chair, so compelling was the sound produced by the DAVE." In particular, he praised the DAVE's "superb re-creation of soundstage depth, its sense of musical drive, and the clarity with which it presented recorded detail." Reporting from his test bench, JA wrote: "Even if I hadn't auditioned Chord's DAVE, I would have been impressed by this DAC. Its measured performance is beyond reproach." (Vol.40 No.6 WWW) Chord Hugo M Scaler: $4795
The Chord Hugo M Scaler is a digital processor but not a digital-to-analog processor, its purpose being the upsampling—referred to in the UK as upscaling—of incoming data. When connected to a Chord DAC via BNC connectors, the M Scaler can upsample up to 705.6kHz or 768kHz, but with non-Chord DACs the upper limits become 176.4kHz and 192kHz. (In all cases, incoming DSD data is converted to PCM, with a 6dB reduction in level.) JA used the M Scaler with Chord's DAVE D/A processor, and with his own PS Audio and Mark Levinson DACs. In all cases, but especially with the DAVE, upsampling via the M Scaler offered such improvements as "more image depth, an increased sense of drive, and even more clarity." That said, owing to the fact that the M Scaler is "relatively expensive," JA recommends auditioning it with your DAC of choice "before getting out the credit card." (Vol.43 No.3 WWW)
w/o headphone amp: $13,500
The "perfectly" named dCS Bartók—judged so by JCA for its modernist, single-box sensibility—brings an unprecedented level of thrift to the company's offerings: It is both the company's most affordable D/A processor and the one that offers the highest level of per-chassis functionality, owing to its inclusion of a headphone amplifier (which can be omitted for a $2750 savings) and an onboard version of the dCS Network Bridge streamer, the latter allowing playback from streaming services, network storage devices, and USB-connected flash drives. At the heart of the Bartók remains the manufacturer's patented Ring DAC technology, here supporting native sampling rates up to 24-bit, 384kHz and up to DSD128. According the JCA, the Bartók "consistently and unambiguously revealed the character of the recordings it played, with clarity, pinpoint imaging [and] excellent image depth, fully saturated tonal colors, and no noticeable emphasis on any part of the frequency spectrum." Although neither writer saw the other's work until press time, Jim's conclusion—"the state of the art"—was echoed by JA in his test-bench report: "In this crusty old engineer's view, 'dCS' means 'Digital Done Right!' (Vol.42 No.10 WWW) dCS Network Bridge: $4750
Designed for use both with the company's top-of-the-line Vivaldi DAC and other DACs, the dCS Network Bridge is a Roon-ready, one-box network player that can serve as a bridge between the user's NAS (or other such file source) and DAC, and can also stream content from Tidal, Spotify, and other services. Ethernet, AirPlay, and USB inputs are offered, as well as BNC inputs for an external clock; outputs are a pair of dCS-compatible AES/EBU XLR sockets and a single S/PDIF RCA jack. Supported formats are PCM to 24/384 and up to double DSD, either native or DoP. (WiFi performance is limited to 24/96.) JVS found that even before the Network Bridge was fully warmed up, it delivered "instrumental textures [that] were far more palpable than before," compared to his own dCS Rossini DAC/player. After extended listening, JVS declared that the dCS's sound was "demonstrably superior to conventional computer-audio playback via USB," and described the Network Bridge as "an invaluable—I'd say indispensable—asset for owners of a Vivaldi or older dCS DAC." (Vol.40 No.12 WWW) dCS Rossini DAC: $23,999
Were you to discard or disable the disc transport in your dCS Rossini Player, you would essentially have a Rossini D/A processor—which, like the Rossini Player, upsamples to PCM 352.8kHz or 384kHz and supports both DoP and native DSD up to DSD128. That said, if you wish to use the Rossini DAC to enjoy SACDs, you'll need a separate dCS transport, such as the dCS Vivaldi ($41,999). In the January 2017 Stereophile, JVS described using the Rossini DAC in place of his dCS Puccini player: "The Rossini seemed to dive into the center of the music and bring it home in ways the Puccini could not." In the May 2018 Stereophile, Jason reported on using a Rossini DAC that had been upgraded with full MQA compatibility: "The improved sound the Rossini drew from [my] MQA tracks was easily audible, and took recorded sound to another level, viscerally and emotionally." In the June 2019 issue, JVS reported on dCS's Rossini software v2.0, which applies to both this product and the Rossini Player. (Vol.40 No.1, Vol.41 No.5, Vol.42 No.5, Vol.42 No.6 WWW)
EMM Labs' newest product is the first D/A processor to make use of the company's new VControl, a high-resolution volume-control system. Of its seven digital inputs, the DV2's USB Type B input is its most versatile, enabling PCM conversion up to DXD, DSD up to DSD128, and full MQA unfolding. Also provided are two coaxial (RCA) S/PDIF inputs, two optical (TosLink) S/PDIF inputs, one AES/EBU (XLR) input, and one proprietary EMM Optilink for SACD and CD playback. In his listening tests, JVS tried using the DV2 in a variety of configuration; he noted that, by the time he'd done so, "it had become clear that the DV2 is one of the finest-sounding DACs with volume control that I've ever heard in my reference system." Indeed, Jason praised the DV2 for delivering, compared to other processors he's enjoyed in that setting, "the smoothest, most naturally warm, most consistently engaging and non-fatiguing reproduction of music." Writing from his test bench, JA noted that the DV2 offers resolution that's "close to the state of the art." (Vol.42 No.3 WWW) exaSound e38 MkII: $4299
The e38 was introduced in 2017 as the third-generation version of exaSound's multichannel DAC, preceded by the e18 and the e28. In 2019, exaSound introduced the e38 MkII, which replaced the ESS ES9028PRO chip of the original e38 with ESS's new ES9038PRO DAC, said to have four times as many internal paralleled DAC channels. There are also redesigned reference voltage sources and master clock power circuits as well as redesigned mainboard and output stages. Reviewing a sample of the e38 MkII equipped with balanced mini-XLR outputs—an all-single-ended-output version can be had for $3999—KR found that the MkII "was somewhat more detailed and open compared to the original." Kal's conclusion: "By today's standards, this one is pretty much beyond criticism." (Vol.40 No.7, Vol.42 No.9 WWW) Meridian Audio Ultra DAC: $23,000
The MQA-compatible Ultra DAC offers both balanced (XLR) and single-ended (RCA) outputs, virtually every kind of digital input you can imagine, and at least one you might not: a SpeakerLink connection, for use with Meridian's digital active loudspeakers. The Ultra DAC boasts a presumably futureproof card-frame construction, with separate dual-mono DAC cards, a high-current clock card, and a first-in, first-out (FIFO) buffer card, intended to minimize jitter. The power supply is linear as opposed to switch-mode. Alongside MQA, Meridian's flagship is compatible with PCM up to 24/384, as well as DXD files and DSD64 and 128. Signal-polarity inversion and EQ are available via the DAC's menu system, and the user has a choice of Long, Medium, and Short reconstruction filters. Used with PCM files, JA's first impressions of the Ultra DAC were of "a smooth sound with superb transparency and soundstage depth," and he praised its low-frequency performance as "powerful and extended." While listening to an MQA file of pianist Robert Silverman JA noted that "the MQA recording presented the width and depth of the Steinway in an uncannily realistic manner." Taking over from JA the listener, JA the measurer praised the Meridian's low distortion and good rejection of word-clock jitter. Both JAs agreed that the Ultra DAC joins dCS's Rossini and Vivaldi DACs in offering "the best sound I have enjoyed from digital recordings." (Vol.40 Nos.5 & 6 WWW)
Offering MQA, DXD, DSD256, and PCM up to 32-bit/384kHz, the Mytek Manhattan II is, in HR's words, "a complete digital and analog service provider." Add Mytek's optional phono card ($1495) and it becomes a phono preamp; add its Roon-ready WiFi card ($995) and it becomes a network streamer with maximum throughput of 24/192 and DSD64. Also on tap in the base model are a discrete, high-current headphone amp, and a user-selectable choice of seven different filters for CDs and PCM files. After sampling some of his favorite MQA files through the Manhattan II, HR asked: "If you were contemplating the purchase of a new DAC, why would you not want it to include MQA processing?" As for its performance with CDs, he wrote, "the Mytek let my mind rise and then look down on the musical stream, to observe the matrix of its notes and silences." Overall, he praised the "uniquely non-digital"sounding Mytek Manhattan II for "[reproducing] recordings in a manner that seemed devoid of mechanicalness or electronic artificiality. Class A all the way." JA summed up the results of his lab tests in one short sentence: "Mytek's Manhattan II offers superb measured performance." (Vol.40 No.9 WWW) Playback Designs Sonoma Merlot: $6500
Designed and released at the same time as Playback Designs' Sonoma Syrah music server (see elsewhere in this edition of "Recommended Components"), and housed in a similar-looking enclosure 12" wide by 3.25" high by 9" deep, the Sonoma Merlot stereo DAC offers the usual USB, S/PDIF, and AES/EBU inputs, plus Playback's proprietary PLink, for connection to their USB-XIII Digital Interface ($2500), which acts as a master clock in multichannel systems. On its USB and PLink inputs, the Sonoma Merlot provides up to 24-bit/384kHz PCM resolution, and does DSD up to DSD256; the remaining inputs are limited to 24/192 and DSD64. A headphone amp with a front-panel 1/4" jack is also provided. After borrowing and using three (!) Sonoma Merlots—the extra two were required for surround sound—with the above-mentioned server and digital interface, KR praised the system's "beautiful sound." Using the Sonoma Merlot with his Baetis Prodigy X server and comparing that combo with his exaSound e38 multichannel DAC, KR found that "soundstage detail was equal" between the two, but that "the exaSound was a bit more forward," and the trio of Merlots "more naturally arrayed." (Vol.40 No.9 WWW) PS Audio PerfectWave DirectStream DAC: $5999 ★
Instead of an off-the-shelf chipset, PS Audio's first DSD processor uses original code written into a field-programmable gate array (FPGA), the result being a system that converts all incoming data to double-rate DSD. In addition to asynchronous USB, the digital inputs include RCA, TosLink, and HDMI, and single-ended and true balanced analog outputs are provided. The DirectStream is built on a cast-alloy chassis with a glossy MDF top and a touchscreen from which all user controls can be worked. Firmware is user-updatable, as AD discovered while reviewing the DirectStream. He noted the DAC's "excellent pacing, flow, correctness of pitch relationships, and the like, as well as a consistently smooth and slightly laid-back sound." With some files, AD found the DirectStream just a little too laid-back—a condition mitigated in part by an early firmware update—but found its musicality beyond reproach. JA observed that the DirectStream "measures superbly well" in many ways, but was troubled by its poor linearity at low frequencies and its "ultimate lack of resolution" with hi-rez files. In a Follow-Up, RD tried the DirectStream DAC with PS Audio's PerfectWave Memory Player transport ($3995) and observed, "listening to familiar recordings . . . I heard more musical detail from them than I previously had." Subsequent to that audition, RD received and installed in the DirectStream DAC a new firmware upgrade, bringing his unit to v.1.2.1; he liked it. Following the firmware update to v.1.2.1, JA re-tested the DirectStream DAC and found evidence of a lower noise floor, increased low-level linearity, and a dramatic reduction in low-frequency distortion. Said JA: "Kudos to PS Audio for designing a product so that its performance can so easily be upgraded by its customers." There have followed three additional, successive firmware upgrades; in 2017, the most recent of these, named Huron, impressed JCA as "a clear improvement over [its immediate predecessor], which was already very good." (Vol.37 No.9; Vol.38 Nos.2, 3, 5, 11; Vol.39 No.11; Vol.40 No.10 Vol.42 No.6 WWW)
The German-built T+A Elektroakustik DAC 8 DSD incorporates two distinct sets of D/A converters: DSD signals are treated to 1-bit conversion and are never converted to PCM, while PCM signals are treated to four DACs per channel in a double-differentiation configuration that, according to JI, is claimed to "perfectly cancel out converter errors and nonlinearities while increasing dynamic range by 6dB." Also on tap are four user-selectable digital filter options, independently adjustable volume for line and headphone outputs, and separate, user-selectable analog filters for DSD and PCM, the former intended to protect the rest of the user's system from ultrasonic noise. JI praised the DAC 8 DSD for "approach[ing] the performance of cost-no-object designs" and "represent[ing] good relative value." JA gave the DAC 8 DSC a clean bill of health, with particular regard to its "superb rejection of word-clock jitter via its PCM inputs," while noting that "its measured behavior and sound quality [are] so dependent on which of its four digital filters is in use." (Vol.39 No.10 WWW) A CanEver Audio ZeroUno: $9950
While digital processors with tubed output sections aren't new, the Italian CanEver Audio ZeroUno breaks with convention by looking less like a DAC than a 2A3-fueled power amp, its two Coke-bottlestyle CV181 dual-triode tubes enjoying pride of place atop a distinctly attractive case. Under its skin is an ESS Sabre32 ES9018S chip, its eight internal differential DACs used in a quad-sum configuration. Supplementing the ESS chip are multiple PCM and DSD filters of CanEver's own design, selectable via a menu system that also provides a switchable jitter filter, signal-polarity inversion, channel balance, and other niceties. The ZeroUno supports PCM to 384kHz and DSD64 and 128 as DoP; newer versions of the CanEver DAC are said to provide MQA compatibility, though that was not available at the time of our review. AD noted shortcomings in the ZeroUno's manual, especially when it came to navigating its software menu—we're told that this, too, has been refined in current production—but forgot those complaints after noting that the Italian DAC made his favorite files sound more colorful and "less hi-fi" than what he's used to hearing from digital playback. Art's conclusion: "I've heard no other digital product that succeeds quite so well . . . at letting music sound like music." Writing from his testing lair, JA noted the ZeroUno's "respectable measured performance," but cautioned users to keep its jitter and oversampling filters switched on. (Vol.40 No.5 WWW) Chord Electronics Qutest: $1695
JA, who regards Chord Electronics' upmarket DAVE ($12,488) as "one of the best-sounding DACs I've had in my system," jumped at the chance to review Chord's far less expensive Qutest, which draws from the same well: It's based on the company's proprietary 10-element Pulse Array Design processor, designed by Rob Watts and implemented in a Field Programmable Gate Array (FPGA) chip. Via its USB port, the compact (6.3" wide by 1.6" high by 2.85" deep) Qutest handles DSD256 (as DoP) and PCM up to 768kHz, but lacks MQA decoding. In his listening observations, JA praised the Qutest for "the excellent sense of motion" it lent to a favored piano-concerto recording, from which he also heard "stably and clearly positioned" stereo images, if not quite the soundstage depth he'd hoped for. JA the measurer uncovered, among other things, the fact that the Chord Qutest "offers almost 21 bits' worth of resolution, which is close to the state of the art." JA the reviewer concluded: "strongly recommended." In a Follow-Up, HR described his own experiences with the Chord Qutest, in which he noted that this DAC "might be doing something unusually right in the time domain." His conclusion: "a must-audition for every serious audiophile." (Vol.42 Nos. 1 & 3 WWW)
In creating the Brooklyn Bridge, Mytek essentially took their Class A Brooklyn DAC+ ($2195)—a high-resolution processor that supports 32/384 PCM, DSD to DSDS256, and full MQA unfolding, and also includes a headphone amp and a line-level and phono preamp—and updated it with streaming and network server capabilities, via wireless or Ethernet connections. Qobuz, Tidal, Deezer, vTuner, and Spotify are supported. As JCA wrote, "The Brooklyn Bridge aspires to and approaches sonic neutrality. I hear a rich, detailed sound with fullness and depth but without exaggerated lows, and with a crystalline quality in the highs," and noted that, as the only streamer he's aware of "that incorporates a DAC used in studios," it is in a class by itself. (Vol.42 No.9 WWW) Mytek HiFi Brooklyn DAC+: $2195
Mytek, which has its roots in the pro-audio industry, took aim at the consumer-audio marketplace with their original Brooklyn-made Brooklyn DAC ($1995), which also functions as a line-level preamplifier, a two-output headphone amplifier, and MM/MC phono preamp. The compact (8.5" wide) Brooklyn offers 32-bit performance via USB, 384kHz PCM resolution, and can handle up to DSD 11.2896MHz as well as unfold MQA files. Selectable digital filters are offered, as are controls for volume (the user's choice of analog or digital), balance, mono, and signal-polarity (phase) inversion. JCA, who preferred the Mytek's sound with its volume control set for analog, reported having a hard time getting a handle on the Brooklyn's sound, but once he did, he heard "bass instruments reproduced fully and cleanly," a soundstage that was "deep and layered," with images "precisely positioned in space," and a sound that was, with all but the lousiest recordings, "very open." Writing from his test bench, JA praised the Brooklyn's "very low" noise, "superb" rejection of word-clock jitter, and an "excellent" signal/noise ratio—among other things—from its phono stage, concluding, "the Mytek Brooklyn's measured performance is superb . . . color me impressed." In the May 2017 Stereophile, KR described using three Mytek Brooklyns to play multichannel MQA recordings from 2L Recordings, prompting from Kal this reference to JCA's Brooklyn review: "I can echo his sentiments about its revelation of soundstage and texture." In the same issue, Brooklynite HR summed up his own experiences with the Mytek, through which he enjoyed streaming MQA-encoded Tidal Masters files: "I'm happily addicted to MQA, Tidal Masters, and the Mytek Brooklyn." In the April 2017 Stereophile, JCA reported on this product's latest incarnation, the Brooklyn DAC+ ($2195), which is built around the new ESS Sabre 9028 Pro DAC chip, and offers an improved analog attenuator circuit and other refinements. In a side-by-side comparison of the two Brooklyns, JCA heard little difference: "There may have been a slight increase in transparency in the upper midrange/lower treble with the DAC+," he said, but at the end of the day JCA got "superb [sound] from both Brooklyns." (Vol.39 No.11, Vol.40 No.5, Vol.41 No.4 WWW) Pro-Ject Pre Box S2 Digital: $399 $$$
This combination D/A processor and headphone amp measures just 4.1" square and 1.4" high and uses dual ESS Sabre Pro ES9038 chips to offer up to 32-bit/768kHz PCM and DSD up to DSD512, plus eight user-selectable PCM reconstruction filters and full unfolding of MQA files. In using the Pre Box S2 Digital to compare MQA files to their non-MQA versions, KM wrote that "the soundstage seemed to grow and surround my head," describing the Pro-Ject DAC's MQA performance as "a revelation." Ken praised the DAC's user-friendliness and concluded, "I can think of no other mini-machine that does so much so well." Writing from his test bench, JA observed very low noise—"extraordinarily good, considering that the Pre Box S2 Digital is powered by a tiny wall-wart supply. Someone at Pro-Ject knows how to optimize a printed-circuit-board layout!" In a Follow-Up report, HR wrote that the Pre Box S2 Digital "preferred sensitive, easy-to-drive headphones" such as his own AudioQuest NightHawks, judging that combination "lively, smooth, and very musical." (Vol.42 Nos.4 & 5 WWW)
Is high-end audio ready for a company whose all-out statement DAC costs only $2299? Ready or not, Schiit Audio's Yggdrasil is here, offering what Schiit describes as a true "21 bits of resolution" and proprietary digital filtering, implemented on an Analog Devices processor, that retains rather than destroys "all the original samples." Also featured is a hefty regulated power-supply section built around twin transformers: one for the digital supplies, the other for analog. Input signals of resolutions up to 24-bit/192kHz are accepted. According to HR, in contrast with the "grainlessness" of the Mytek Brooklyn DAC, "the Schiit's sound was slightly textured, and dynamic contrasts were less evident." That said, Herb also observed that "the Yggdrasil exposed melodic lines . . . and human voices—also better than any DAC I've heard costing less than five grand." JA's measurements comprised a mixed report, with praise for the Schiit's "superbly well designed" analog circuitry set against his impression of "digital circuitry [that] is not fully optimized." In 2018, Schiit introduced their Analog 2 upgrade—two new output cards and a firmware update for the DSP board—available to owners of older Yggdrasils for $550. HR wrote in a Follow-Up that the upgrade, which must be performed by Schiit or by an authorized service center, allowed his Yggdrasil to sound "quieter, more refined, more transparent, more silky, more tactile." (Vol.40 No.2, Vol.41 No.9 WWW) B DSPeaker Anti-Mode X4 Preamplifier-DAC: $4250
The Anti-Mode X4 is a full-featured two-channel line-level preamplifier plus DAC with multiple inputs—single-ended and balanced analog inputs, plus USB, S/PDIF, and TosLink digital—multiple outputs, and, as KR describes it, "a head-spinning array of digital-signal-processing (DSP) tools." It also comes with a calibrated microphone and stand, for use with its many DSP functions—including room/speaker EQ for full-range speakers and for subwoofers; subwoofer level control; bass and treble tilt controls; infrasonic filtering; and a L–R balance control. A promised EQ function for four subwoofer channels has yet to materialize—but even so, KR found the Anti-Mode X4 in its present state to be useful, effective, and altogether "great just as it is." (Vol.42 No.5 WWW) iFi Audio Pro iDSD: $2749
Built around four Burr-Brown DSD DAC chips operated in what iFi calls an "interleaved" array, the Pro iDSD offers up to DSD1024 and 32-bit/768kHz PCM—and more controls and performance options than can be fully described in a review of reasonable length, let alone a little blurb like this. Suffice it to say the iFi contains a three-output, selectable-gain headphone amplifier, has built-in support for streaming from Qobuz and Tidal, performs full unfolding of MQA files, has balanced (XLR) and unbalanced (RCA) outputs, offers defeatable upsampling with a variety of user-selectable filters, and, among its many other output options, contains a user-selectable tubed output circuit. HR said of its performance on an especially beloved Sun Ra recording, "the Pro iDSD's DAC did a sterling job of sorting out the countless spatial layerings of this track," and added the iFi to his "short list of DACs that recover an enjoyable illusion of dense bodies playing music." Measuring the iFi proved to be a mammoth task—"With so many output options and operating modes, it's easy to become confused about the iFi Pro iDSD's performance," JA noted—but in the end, despite a couple of puzzling idiosyncrasies, he found "much to admire in its measured performance." (Vol.42 No.1 WWW)
More than one Stereophile scribe has sung the praises of Mytek's original Brooklyn DAC, known as much for its extras—an onboard line-level preamp with analog volume control, an MM/MC phono stage, and a two-output headphone amp—as for being a great-sounding D/A processor. Now comes the Mytek Liberty, a stripped-down model said to be the sonic equal of the original Brooklyn (which has since been replaced by the even better-performing Brooklyn DAC+: see elsewhere in "Recommended Components"). Built around a 32-bit ESS Sabre DAC chip, the Liberty offers, via its USB input, PCM performance up to 24/384 and DSD up to DSD256. Gone are the preamp, the phono stage, and one of the two headphone outputs; retained is full MQA compatibility. The Mytek Liberty impressed AD with its musical capabilities, including good senses of momentum and touch, and by sounding appropriately crisp while "never [becoming] gritty." In measuring the Liberty, JA noted resolution to almost 19 bits, which is quite good, and said that the DAC's measured performance "indicates excellent digital and analog engineering, especially considering its affordable price." Quoth AD: "Very highly recommended." (Vol.41 No.11 WWW) Prism Sound Callia: $1899
The first domestic product from UK-based pro-audio specialists Prism Sound, the Callia D/A converterheadphone amplifier is based on a dual-mono pair of Cirrus Logic CS4398 DAC chips, and accepts DSD data up to DSD128 and PCM to 384kHz, though the former is converted to PCM and the latter is downsampled to 192kHz. Its front panel is graced with two separate volume controls: one for the Callia's line outputs, the other for its front-mounted 1/4" headphone jack, further enhanced with a three-position DIP for optimizing the output for low-, medium-, and high-impedance 'phones. When JA used the Callia to drive his Audeze LCD-X headphones, he described the sound as "richer than I expected," while in his Big Rig—without a preamplifier, and with the Callia's own volume control doing the honors—the sound was "drier," with less soundstage depth than JA gets from his PS Audio PerfectWave DirectStream DAC, but no loss of power from drums and electric bass. JA praised the "excellent-sounding" Callia, but described the Mytek Brooklyn's sound as "slightly better"—and noted that the then less expensive Mytek adds MQA compatibility. Apart from some surprising jitter-related (as opposed to power-supplyrelated) sidebands, the Callia performed respectably on JA's test bench. Significant price reduction as of July 2018. (Vol.41 No.4 WWW) C Arcam irDAC-II: $749 $$$
Fresh from flings with four- and five-figure DACs, JA reconnected with the hoi polloi via Arcam's affordable irDAC-II, introduced in 2016 to celebrate the British company's 40th anniversary. Built around the ESS ES9016 K2M DAC chip, the Arcam combines five digital inputs—two RCA, two TosLink, one USB—with Bluetooth connectivity and a headphone amplifier, and supports files up to DSD128. After using an AudioQuest Cheetah interconnect to wire the irDAC-II directly to his power amps—the former has its own volume control, thus eliminating the need for a preamp—JA was impressed by the Arcam's cleanness, clarity, and definition with a variety of tracks, though he noted a shallower-than-expected soundstage with some material, and felt its balance was a little lightweight—also a characteristic of the irDAC-II's headphone output. That said, via his AudioQuest NightHawk headphones, the Arcam outperformed the Meridian Explorer DAC: with one recording in particular, the irDAC-II "opened up a somewhat cleaner, clearer view into the recorded acoustic." As for the Arcam's Bluetooth performance, JA described it as "always listenable, if not completely involving." Writing from his lab, JA praised the irDAC-II as "a conventional but well-engineered D/A processor." (Vol.40 No.7 WWW)
In BorderPatrol's Digital to Analogue Converter SE the processor of choice is the same Philips TDA1543 16-bit chip found in playback gear from the 1980s and '90s, implemented without a digital reconstruction filter, energized by analog power supply with twin mains transformers and a tube rectifier. It has two inputs—USB and S/PDIF—and is built with a copper chassis, upgraded signal and power-supply capacitors; non-SE versions with a single input, more modest caps, and no rectifier tube are also available. HR wrote that the DAC SE "delivers refined, human-sounding musical pleasures—at a very reasonable price." Writing from his testing lab, JA noted a severe channel imbalance with data sampled at rates higher than 96kHz, channel-specific anomalies in linearity error, a higher-than-expected noise floor, and disappointing performance in its rejection or word-clock jitter. In a Follow-Up that proved controversial, JI described comparing the Border Patrol DAC SE with his Benchmark DAC2 HGC, concluding that the BorderPatrol "purred like a sweet, sultry voice . . . even as it lied to me." (Vol.41 Nos.9 & 11 WWW) K Denefrips Ares R2R DAC. Deletions
Auralic Altair, Chord Hugo TT, HoloAudio Spring Kitsuné Tuned Edition Level 3, replaced with newer models not yet reviewed. Bryston BDA-3, Moon 780D, TotalDac d1-tube-mk2, not auditioned in a long time.
