Estimated reading time: 9 minutes
By way of full disclosure, I have reviewed, enjoyed and owned a number of Paul McGowan’s PS Audio products. Whether analog or, as in this case, digital gear, PS Audio components have consistently demonstrated high performance at reasonable prices and often had innovative designs that were ahead of their competitors. Nine years ago, PS Audio introduced the DirectStream DAC, a new DAC, that used a Field Programmable Gate Array (FPGA) to reduce noise and jitter. Two years ago, this technology was carried over to its new disc player the PerfectWave SACD transport, that also featured a galvanically isolated output stage. Not content to rest on its laurels, this company recently brought out its new flagship DAC, the DirectStream MK2, with design changes that promised to improve its performance over that of its highly regarded predecessor. In addition to galvanically isolated inputs, the MK2 also has galvanically isolated outputs, grounds, and power sources.
The DirectStream MK2 now has two FPGAs as the core processors. Its power supplies and each of the seven inputs—a pair of XLRs, one coaxial, one optical, one USB, and a pair of I2S ports—are galvanically isolated, so there are no physical connections from the source to the rest of the DAC. All inputs can be connected at the same time without sonic penalties. The optical input is capable of 96kHz, 24 bit audio. XLR/EBU up to 352.8kHz PCM and DoP128 (DSD over PCM) in double XLR output mode. I2S and USB can handle up to 705.6 kHz PCM and DSD256. Other disc transports will work with this DAC but unless they have I2S-compatible or USB outputs, they will only transfer DoP at DSD 64 and PCM up 192 kHz via single XLR or Coaxial outputs.
Data gets upsampled to 20 times DSD before processing and, after processing, is converted to four times DSD and the output goes to a passively filtered analogue section. There is an extra 6 dB of head room in the analogue path beyond the 6 dB of head room used by SACDs. The output of the DSD engine is fed directly into the galvanically isolated output stage, using high speed differential video amplifiers, essentially Class A switches, and a passive output transformer.
The thorough owner’s manual (which now must be downloaded from the company’s website) should be read before proceeding with the set-up, particularly with regard to navigating the submenus. The upper left of the front panel has the now-familiar PS Audio blue button that takes the DAC in and out of standby mode. Like the cosmetically similar PerfectWave SACD transport, the MK2’s new front panel has exchanged its predecessor’s small color screen for a smaller black screen with highly legible blue numbers for volume level and much smaller text for active source that, when it is selected, turns on a green light just above the volume display. A small black button at the left of the screen opens the various menus and on the right of the screen is a control ring for adjusting volume, selecting sources, playback commands, and navigating submenus.
The main menus enable adjustment of balance, phase, pre-emphasis, and display of current firmware versions. There are four submenus: (1) Audio input allows naming inputs and lifting all input grounds except for that of the optical input; (2) Audio output selects either fixed or maximum volume, balanced or unbalanced outputs and enables ground lift and shell lift (for XLR cables); (3) System adjusts the back lighting, provides an IR on/off toggle, copies new FPGA loads on a thumb drive, and performs factory reset; (4) Network adjusts network status and enables Wi-Fi set up or modification.
From left to right on the rear panel is a USB port for updating firmware, an on/off power switch, a power cord receptacle, a pair of 12-volt trigger ports, an Ethernet port, the seven above-mentioned input ports and pairs of balanced and unbalanced outputs.
The silver remote control is identical to that supplied with previous PS Audio digital components like the PerfectWave SACD player and the original DirectStream DAC but now the XLR button toggles between XLR inputs and the Bridge button is not operational because there is no longer a Bridge card slot. Later this year, PS Audio will launch its new outboard streaming unit, the AirLens, that will interface with the MK2 DAC via its I2S port.
What Won’t It Play?
The DirectStream DAC MK2 replaced the original DirectStream DAC (DAC 1) in my reference system consisting of a Pass Labs XS Preamplifier, a pair of XS 150 mono bloc amplifiers, a PS Audio PerfectWave SACD transport connected via I2S port, and a pair of MartinLogan CLX speakers and two Balanced Force 212 subwoofers. All interconnects, speaker cables and power cords were Nordost Odin V1.
After a 100-hour break-in period, the sound had really opened up and critical listening began with the MK2 DAC’s grounds and shells lifted. I tried listening with grounds and shells in place and then lifted. The latter mode did sound better in my system. Duke Ellington’s “In a Sentimental Mood”, on Mark Levinson’s Live Recordings at Red Rose Music SACD presented a warm, well-articulated account of Chico Freeman’s breathy saxophone and George Cable’s 9-foot August Förster concert grand piano, sitting front and center in my room. I heard pauses, clicks, and other sonic details that had been barely audible during the many times I have played this cut with other equipment including the original DAC 1. Sonny Boy Williamson’s Keep it to Ourselves, Analogue Production’s classic, has been remastered in the DSD format as well. Okay, it is a remaster of a remaster of a 1963 analogue recording. On “Don’t Let Your Right Hand Know.” Sonny Boy’s mesmerizing mouth harp, and the varied timing and intensity of his intermittent foot stamping and finger snapping were stunningly reproduced by the MK2. Another marvelous recording of two iconic artists, Ella Fitzgerald and Louis Armstrong (Ella and Louis, UltraHD FIM CD), displayed a warmth, depth, and flawless projection of these two contrasting voices and their backup band better than I have ever heard them, making me forget that this was a 1956 mono recording!
Reference Recordings produced a limited number of DVD-R (WAV 176.4kHz/24bit) recordings that were, in my opinion, as good as bit-perfect digital sources get. Eiji Oue leads the Minnesota Orchestra through an all-Stravinsky program featuring The Firebird Suite with its room-rattling bass slam at about the 9-minute mark. What got my attention this time around was the articulation of the very quiet low frequency opening that, on less resolving players and DACs, simply fails to show up.
A JVC XRCD version of one of the best vocal/piano recitals ever made, The Tony Bennett Bill Evans Album, followed and from the first cut, “Young and Foolish,” I was swept away by how natural the quaver and decay of Tony’s voice sounded and there was a slight studio echo that I had not previously noticed.
Finally, the many listening sessions concluded with a selection from Earl Wild: The Art of Transcription–Live from Carnegie Hall. This towering 1981 recital of unabashed keyboard masterpieces contains a thrilling piano version of Bach’s “Toccata and Fugue in D Minor” with keyboard pyrotechnics that brought the house down. Imaging getting a front row seat and hearing absolutely every keystroke and pedal coming right at you. Well, that’s what the DAC MK2 delivered!
What about the original DirectStream DAC versus the DAC MK2?
This may be the most important question for those who own the previous DAC 1 which has been one of my reference digital components for more than six years and was a trail-blazing unit when it was released. I put the DAC I on the shelf next to the DAC II and ran side-by-side comparisons with each connected to the Pass Labs XS preamp with Odin VI XLR cables. Each DAC received the same source material played by the PWT SACD transport. I turned down the level of the MK2 (maximum output of 4 VRMS/balanced) to match that of the DAC I (2.8 VRMS/balanced). As good as the DAC I was, its successor generated more air, recovered more details, and produced more analogue-like warmth belying the fact it was a digital component. DAC I owners need not despair, since PS Audio is offering a generous trade-in offer for their units should they decide to upgrade.
The Final Assessment
This PS Audio DAC/transport combination, both using galvanic isolation to minimize digital noise, led to outstanding recovery of previously masked details and phenomenal projection of voices and instruments into my sound room. The MK2 costs $7999.00 and mating it with the PerfectWave SACD transport will run up the tab to nearly $15,000.00. Having heard some stratospherically priced DACs, I can unequivocally say that this one easily surpasses its competition at this price point and holds its own with far more expensive DACs. Highest recommendation.
PS Audio DirectStream DAC MK2 is available for purchase now from PS Audio and their certified dealers.
- Flawless operation
- Excellent build quality
- Analogue-quality sound
- Excellent owner’s manual
- Solid remote control
- Firmware upgradability in the field
- Performs best if paired with a PerfectWave SACD Transport via I2S inputs
Physical: Weight 21 lbs [9.53 kg], Dimensions 14” x 17” x 4” [ 36cm x 43cm x 10cm]
Power Requirements: Model specific 100VAC, 120VAC, or 230VAC 50 or 60Hz
Power Consumption: 25 Watts
Digital Audio Inputs: I2S (2), Coax, XLR Balanced (2), Optical, USB
Analogue Audio Output: RCA single ended or balanced, XLR balanced
Output Level: High, maximum: 4 VRMS Balanced, 2 VRMS Single Ended
Output Impedance: <100Ω/<200Ω
Frequency Response: 20-20KHz +/- 0.25dB
THD+N @ 1KHz (full scale): <0.1%
Format: PCM or DSD
Sample rate (PCM): 44.1kHz, 48.0kHz, 88.2kHz, 96.0kHz, 176.4kHz, 192kHz, 352.8kHz; 705.6kHz
Word length (PCM): 16b, 18b, 20b, 24b
Data Rate (DSD): Standard (2.8MHz) or Double (5.6MHz) DoP; raw DSD on I2S and USB inputs