Steven
It has occurred to me that some audiophiles will find the new Playback Designs MPD-8 Dream DAC (US$22,000) to be an audacious name for a new product. But those of us that have been familiar with the work of Andreas Koch and Playback Designs might not find the name of Dream DAC to be as overconfident as this appellation implies.
With the introduction of the Sonoma Series in 2016, Andreas Koch, CEO, engineer, and founder of Playback Designs with his associate engineer, Bert Gerlach, have introduced a significant offering of new products. Included in the Sonoma series was the Merlot DAC, a product that I had the good fortune to enjoy listening to over a two-month period shortly after its release. At that time, I found the $6500 Merlot DAC to be very impressive sounding when paired with the company’s Syrah Server. While I had experienced earlier Playback Designs DACs since the company’s first product offerings in 2008, the Merlot was something very special in terms of its function and sonics that made me wonder what could be created if Koch and Gerlach pulled out all the stops for a top-of-the-line DAC.
Andreas Koch has had an extensive background as a design engineer. He began his employment with Studer ReVox in Switzerland in 1982 where he designed the world’s first fully asynchronous digital audio sample rate converter. In 1985 he designed the digital signal processing for the Dolby Labs AC-1 and AC-3 digital encoders. In 1987 he returned to Studer ReVox where his expertise was utilized in the development of a 48-channel digital audio tape recorder. Other work for Studer included the development of the Dyaxis hard disc recorder. But it was his management and development of Sony’s Sonoma, the world’s first 8-channel DSD recording / editing / mixing machine in 1997 that gave him his extensive experience in DSD; experience that would find its way into work for EMM Labs in 2003, and later in the formation of Playback Designs in 2007.
Playback Designs has never relied on the use of standard off-the-shelf chips for digital processing beginning with the MPS-5 SACD Player/DAC in 2008 and continuing to their most current DAC offerings. Koch has developed an FPGA (Field-Programmable Gate Array) with proprietary algorithms. This feature will be appreciated by audiophiles in that the FPGA can be easily upgraded by the user when new algorithms are available.
I should also mention the contribution of Bert Gerlach to the design of the MPD-8. Bert designed the PCB layouts for the analog and digital circuits. Bert has also developed the analog circuitry of Playback Designs products including that of the MPD-8.
The MPD-8 is a large DAC tipping the scales at 42 pounds. The external aluminum case is very attractive with its dark grey brushed aluminum finish. This enclosure is reminiscent of the discontinued Playback Designs MPD-3 DAC. The faceplate has an elegant appearance with 2 LED displays: one for the volume control and the other showing the input used and PCM / DSD sample rate. This LED display also serves as the settings display. 4 buttons located at the top right of the DAC allow the mute to be toggled on / off, sequential selection of activated inputs, and power standby on / off. There is a master power switch located in the back of the unit.
Included with the MPD-8 is a hefty aluminum remote that not only offers control of the volume and several other functions but allows one to access the settings menu. The remote control also provides the user with the ability to invert the phase of both analog outputs.
The MPD-8 offers a wide range of inputs including asynchronous USB that supports direct PCM sample rates up to 384kHz and DSD up to 11.2MHz. An AES/EBU input supports PCM up to 24 bits / 192kHz and single rate DSD encoded in DoP. The coaxial input is the same as AES, but S/PDIF formatted on an RCA connector. The TOSLINK input is on an optical connector limited to 96kHz max. Playback Designs also offers a proprietary high-quality optical link called PLINK that is used with the MPT-8 Dream Transport. An additional PLINK IN allows a proprietary and high-quality optical link to other Playback Designs equipment that supports PCM up to 384kHz and DSD up to 11.2MHz This PLINK IN input also allows Playback Design to offer external accessory boxes that will allow support of future streaming protocols and encoding formats like MQA.
An Ethernet connection is located on the back of the unit that will allow remote control of the MPD-8 with an iPad or Android tablet in the future. A Reset button on the back panel is used in conjunction with software upgrades.
Playback Designs has not skimped on the design of the power supply of the MPD-8. This DAC offers 3 regulated power supplies with 3 transformers. The design of the analog stages is double differential offering balanced outputs as well as single end outputs. The left and right output channels are built on separate circuit boards with completely separated power supplies.
The MPD-8 has an analog volume control that allows one to power amps directly. This digitally driven analog volume control can be bypassed in the setup feature with selection of one of 5 fixed output settings in the following values: -6db, -3db, 0db, +3db, +6db.
I asked Andreas Koch a series of questions concerning the design of the MPD-8:
How does the new Dream DAC design differ from the previous Playback Designs MPD-5 DAC?
“The Dream DAC is all about separation between analog and digital, between left and right, between power supplies and between clock generator and digital inputs. For this we have used separate PCB’s for each analog output channel, separate power supplies for each analog output channel and digital circuit (3 in total), designed each entity on its own individual ground plane, used multiple stages of power regulation and gave each entity its own programmable resource. Each analog output stage is double differential – i.e. 8 identical circuits for stereo output. All are design features that the MPD-5 does not have. The core DAC is running at 4 times the rate of the original MPD-5 and therefore allows for much more resolution and better SNR.”
How does the MPD-8 process files?
“All digital input signals (including DSD64) are converted to DSD128 with our proprietary frequency and time domain algorithms that also includes an apodizing filter. DSD256 is processed separately. Before the DSD128 or processed DSD256 signals are converted to analog, we use another proprietary and new algorithm to convert the signal to a different format with a bit rate of 2048 (16 times DSD128).”
Why do you prefer DSD processing in your DAC designs?
“Because DSD is single bit it inherently avoids all non-linearity distortions that multibit converters have. Most of the challenges in a single bit converter are on the digital side where you can use virtually unlimited, programmable and mostly very predictable resources to tackle the job. The signal in our converters right before the actual conversion to analog is so close to being analog already, that the conversion is no challenge at all with no exotic components. That makes the system performance very consistent and predictable. Exactly the reason why SACD was launched 20 years ago.”
To evaluate the MPD-8, I elected to use a variety of products / computers to elicit the best audio from its USB input allowing me to take advantage of the MPD-8’s ability to play DSD256 and DXD (352.8 kHz). I used Roon Server as my music software and configured playback (Roon Core) on an Asus G701VI laptop running Windows 10 Pro 64 (Version 1709) with AudiophileOptimizer 2.20. The Asus G701VI possesses an overclockable Intel Core i7 6820HK processor with 32 GB DDR4 2400Mhz SDRAM and a very fast PCIe Gen3 X4 NVMe SSD. The Asus laptop was plugged into a Shunyata Research Hydra DPC-6 v2 distribution center to firewall the noise generated by this computer from contaminating my AC line.
The MPD-8 was placed on a Synergistic Research Tranquility Base UEF. It was plugged into a Shunyata Research Triton v3 with a Shunyata Sigma NR AC cord.
Initially, I listened with the Asus laptop via USB. To further enhance the quality of USB playback, I employed a Sonore Signature Rendu SE. The Signature Rendu SE is an audio renderer that accepts an Ethernet audio stream from my Roon Core to provide a very low noise USB output to one’s DAC. The Signature Rendu SE is basically a mini network computer running a modified Linux operating system that is optimized for audio and is housed with an elaborate linear power supply for minimum noise to its USB output. Another nice feature of the Signature Rendu SE is that it can handle Native DSD with support for DSD256 playback from the MPD-8.
During evaluation I also enhanced the output of the Signature Rendu SE by feeding the USB output to an SOtM tx-USBultra USB enhancement device powered by an SOtM sPS-500 power supply using SOtM’s silver DC power cable.
USB cables used were the AudioQuest Diamond and the Wireworld Platinum Starlight USB 2.0.
The best sonic combination was obtained from the Asus streaming to the Roon Ready Signature Rendu SE feeding the USB input of the tx-USBultra to the MPD-8. I know many of you might find this “ultimate” setup overkill; especially if one considers the expense involved. But this is part of the hobby and certainly this setup can be scaled back to allow the user to still achieve excellent sonic results from the MPD-8.
Another available approach for USB audio perfectionists would be to turn off the internal USB interface of the MPD-8 and use the Playback Designs USB XIII as the MPD-8’s USB input. The USB XIII connects to the MPD-8’s PLINK optical input. The optical connection provides galvanic isolation from computer noise negatively influencing the MPD-8. Andreas told me that this approach can make a small, but observable improvement for USB playback.
One feature that is very important to many users is the MPD-8’s digitally driven analog volume control. Using the balanced outputs, I connected the MPD-8 directly to my Ayre Acoustics MX-R Twenty monoblocks. The MPD-8’s analog volume control did not seem to color the sound or detract from the overall quality of sound obtained from the DAC. The remote allowed me to control the volume easily and precisely. Comparing the MPD-8’s analog volume control with my Ayre Acoustics KX-R Twenty preamp resulted in sonic differences that were small, but perceptible. While I favored the overall sound of the Ayre preamp when included in the playback chain, I could easily live with the MPD-8’s direct connection to my power amps.
The MPD-8 offered me a musical adventure that I was not totally prepared for. I expected the performance to be better than the Merlot DAC, but what I heard was something that went far beyond the Merlot’s sonic presentation. In fact, many of the sonic characteristics of the MPD-8 I will be discussing surpass what I have experienced from the best DACs I have listened to. There is one important point I would like to make before discussing the sonics of the MPD-8; evaluation should not be performed until the DAC has at least 500 hours of playback. I also observed noticeable improvement beyond the 500-hour mark that was not difficult to discern.
For me, soundstage reproduction is a very important characteristic of a DAC; especially when one invests in speakers like the Wilson Audio Alexia Series 2 – a speaker that has the inherent ability to portray a large, detailed soundstage.
The MPD-8 presented the largest soundstage I have ever experienced from a DAC. But it goes far beyond just being enormous; it is an honest portrayal of the acoustic space captured on a fine recording. There is no stereo exaggeration with the classic hole-in-the-middle effect. The essential components of soundstage are beautifully rendered with width, depth, and acoustic height that I found to be quite thrilling to experience. There is an acoustic bloom to the sound that allows one to experience a richly layered soundstage with a proverbial tube-like bloom that results in a holographic portrayal of instruments and singers. All of this comes from the wonderful transparency of this DAC that that resolves the low-level information contained in the soundstage.
The MPD-8 is very impressive in the way it portrays the dynamic qualities of a good recording. Many DACs I have heard sound compressed when compared to the MPD-8. Choral music can present a challenge to a DAC in that there is often a congealing of the sound with an associated hardness that is often falsely attributed to the recording. 2L’s DXD recording Ja, vi elsker, combines the Schola Cantorum choir with The Staff Band of the Norwegian Armed Forces that can prove to be an acoustic challenge for many DACs. The MPD-8 was able to reproduce the choir with excellent resolution while not blurring voices or the band playing with the choir. There was an overall ease to the sound that had extended treble without an unnatural irritating edge. In addition, the music and choir emerged from a deep black background that was ultra-quiet.
The macrodynamic qualities of orchestral and jazz recordings provided an excitement to my listening experience with the MPD-8. But this discussion of dynamics should also include micro dynamic changes that contribute to a recording’s believability. While listening to Channel Classics’ DSD256 recording of Rachel Podger and the Brecon Baroque performing Vivaldi’s Le Quatttro Stagioni (The Four Seasons) displayed an example of what I am referring to. The delicacy and rich timbre of Podger’s violin was portrayed with first-rate resolution of transient detail. The complex textures of the string ensemble were easily heard with the MPD-8 allowing one to experience sound that was harmonically rich and dynamic in overall quality.
The focus of the instruments in the Podger recording allowed me to easily identify instruments in the ensemble. But even more important to me was that the overall sound was relaxed and engaging allowing me to truly enjoy the musical presentation from the MPD-8.
Let’s get back to the discussion of the dynamic quality of the MPD-8. I played some of the older Fourplay recordings that had powerful midbass and deep bass. Listening to Fourplay’s Lets Touch the Sky and Between the Sheets; both 16/44.1 recordings, allowed me to evaluate the macro dynamics of the MPD-8 – particularly at the low end. The MPD-8 has the most neutral and best controlled low end of any DAC I have experienced with my system. The bass was tight and impactful with believable weight and slam.
I have a real love for folk style music; particularly when the singers are accompanied by acoustic instruments. The 24/96 Nonesuch title Folk Songs combined the Kronos Quartet with signers Rhiannon Giddens, Olivia Chaney, Natalie Merchant, and Sam Amidon for a unique sound that was very enjoyable heard through the MPD-8. The Kronos Quartet, for those unfamiliar with this group, combined the talents of David Harrington and John Sherba on violin, Hank Dutt on viola, and cellist Sunny Yang. The Kronos Quartet blended beautifully when accompanying the singers by staying in the background and allowing the singers to take front stage. The MPD-8’s sound was pure and direct with a natural presence to the singers’ voices. The Kronos Quartet added gorgeous color and texture to this recording that the MPD-8 reproduced with no obvious coloration. As with the other musical titles I have discussed, the MPD-8’s ability to be revealing, but not at the expense of ease and musicality, made this DAC a cut above the average offering. I simply lost track of time when listening to the MPD-8.
The MPD-8 had absolutely no issues playing any file type that I presented to it be it PCM or DSD. Many DACs claiming performance to 384kHz have sonic issues playing DXD (352.8 kHz) files, or for that matter, DSD (dsf) files. The sound for these DACs is just not as good as that heard at lower sampling rates. The MPD-8 played all files with the same finesse and sonic quality allowing one to fully explore file types without reservation. I found that the MPD-8 also did a marvelous job playing CD quality files. Most of us possess a large stable of ripped CDs that the MPD-8 will breathe new life into and allow one to fully enjoy their music collection.
Andreas Koch believes that DSD is a first-class file format capable of providing excellent sonics. While most of the DSD (dsf) files available for download are DSD64, superior sound can be obtained from Double DSD (DSD128) or Quad DSD (DSD256) files. The MPD-8 has the capability to play Direct or Native DSD as opposed to DoP. Playing DSD files under the DoP (DSD over PCM), results in a 30 to 50 percent increase in CPU processing overhead. This might affect the sound when the DAC is driven directly by a computer. Also, the DoP implementation for DSD256 requires support for PCM at 705.6 kHz and 768 kHz. These high sampling rates pose a significant challenge for both the computer CPU and USB audio interface. Most DACs, including the MPD-8, support DoP with a top limitation of DSD128. Playback Designs provides an ASIO driver for Windows that allows one to play DSD files directly without DoP allowing DSD256 capability. There is also support for Linux playback of DSD256 in products like the Sonore Signature Rendu SE. OSX users will be limited to DSD128 using DoP with the MPD-8. DoP sounds quite good when heard with the MPD-8, but Native playback sounds a little better to me.
I have found DSD64 to be a bit soft sounding and less defined at the high end when compared to hi-res PCM on most DACs. The transient detail and ultimate resolution possible with PCM are just not there with DSD64, although I must admit that this softness is greatly ameliorated with the MPD-8. But the general lack of hardness and midrange richness of DSD64 does make it a desirable audiophile format for many listeners. Double and Quad rate DSD, on the other hand, do not suffer from these limitations and sound extremely natural and real to this listener.
There are a good number of sources for Double and Quad rate DSD files for the classical, jazz, and contemporary folk music aficionados. One source that has delivered a consistent quality product of enjoyable titles is Blue Coast Music.
Blue Coast Music has a good number of DSD128/256 titles; many of which were sourced from the DSD256 original source mixes. The provenance of the titles can vary across the offerings with some recorded in DSD128, DSD256, or taken from the analog master tape.
One title that I particularly enjoyed playing through the MPD-8 was From Way Up Here performed by Jaeger & Reid. I asked Cookie Marenco of Blue Coast Records to discuss the provenance of this album:
“In the case of Jaeger and Reid, we recorded the original tracks live and direct to DSD256. (Some of those original recordings are on a project called Sneak Peek with no overdubs). Later, Jaeger and Reid wanted to add additional instrumentation. At that time, we transferred the DSD256 to 2″ tape and proceeded to record the additional instruments (overdubs).”
“The album was mixed from tape (which uses the analog console), through the analog console to DSD256.”
“I should mention that all my recordings are mixed through the analog console — even the DSD256 recordings go through the analog console and back to the DSD256. I don’t believe converting to DXD to mix inside the Pyramix to make gain, effects, and eq decisions sounds good. We have decided that analog effect and processing sound better than mixing “in the box”.
The quality of sound delivered by the MPD-8 from this DSD256 album was truly exceptional. The overall sound had immediacy and naturalness that proved to be quite appealing to me. The sonic potential of DSD128 and DSD256 files played through the MPD-8 will delight many an audiophile; especially those who otherwise point to vinyl as their preferred format.
The MPD-8 Dream DAC has turned out to be one of the most impressive sounding DACs that have occupied this listener’s system in the last six years of reviewing digital hardware. One of the MPD-8’s most striking characteristics was that it was able to draw me into the music for hours at a time without listening fatigue while constantly displaying state-of-the-art sound that felt ultra-transparent. For me, the Playback Designs MPD-8 turned out to be my Dream DAC and a new digital reference.
Further information: Playback Designs
Associated hardware
Computer: Asus G701VI laptop running Windows 10 Pro 64 bit and Audiophile Optimizer
Mini Network computers: Sonore Signature Rendu SE
USB enhancement devices: SOtM tx-USBultra
Power supplies: SOtM sPS-500, HDPlex 100 and 200, Synergistic Research Transporter SE
External hard drives: G-Technology 24 TB G|RAID Thunderbolt 2 / USB 3
Music
Software: Roon Server
Computer cables: AudioQuest Diamond USB, Wireworld Platinum Starlight 7 USB 2,0
Analog cables: Shunyata Sigma SP Speaker cables, Shunyata Sigma XLR
Preamplifier: Ayre Acoustics KX-R Twenty preamp
Phono preamp: Ayre Acoustics P5-xe
Amplifiers: Ayre Acoustics MX-R Twenty monoblock amps
Speakers: Wilson Alexia Series 2
Power conditioners: Shunyata Hydra Triton v3, Typhon and DPC-6 v2
