Accuphase DC-37 / STEREO 9/2015]
HIFI EXKLUSIV D/A CONVERTERThe Multi-Talent
The brand-new Accuphase DC-37 can handle all data formats
and digests even the DSD signals from its sibling players.

Until now Japanese noble maker Accuphase has bucked the streamer trend. Off

the usual feed lines for digital sound formats they’d rather rely on PC hi-fi via USB.
Beside two dual inputs for optical and coax cables, the DC-37 which, fully in line withthe company tradition shows a painstakingly clean workmanship, therefore offers aUSB interface for data formats up to 32 bit digital word length at 384 kilohertz sample
rate or “double-rate DSD“ with a 5.6 megahertz bandwidth respectively. This should
probably do the trick.
On top there’s also a proprietary “HS-Link“ through which inhouse SACD players cantransmit the normally disabled DSD data stream. Regrettably we’re missing abalanced AES/EBU socket. Instead there’s a well readable display to show what isbeing played. When fed with regular diet, e.g. from a CD player, this may seem lessimportant, but during our tests on the notebook the feedback messages proved to be
incredibly helpful.
We had expanded the iTunes on our Mac-Book Air by the popular Audirvana Plus
utility, which greatly enhances the sound quality because it disables e.g. Apple’sannoying “Sound Manager“. At 59 EUR the price for this tool is no longer worth
mentioning once you have forked out the 8500 EUR onto the dealer’s counter thatAccuphase calls for the DC-37.
Anyhow, like similar tools Audirvana Plus offers multiple setting options and quite
some pitfalls, sometimes cutting down e.g. the sample rate from 192 to 96 kHz
without an obvious reason, so that the control via display is dearly welcome.
Can it upgrade a DP-550?
Apart from the on/off button the front panel houses merely the selector switches forthe six digital inputs plus two pushbuttons to adjust the output voltage e.g. to othersources in the chain. As it turned out the DC-37 had exactly the same level as theDP-550 SACD player which we were using to check the HS-Link and also to clarify
the question if high-end lovers who already own this player worth approximately
10,450 EUR will indeed enjoy listening to their discs on an even higher standard via
the external D/A converter.
Short answer: yes, they will! Owing to Accuphase’s large dream preamp C-3800 with
its remote-switchable inputs and a HMS Gran Finale Jubilee AF twin cable set, we1

had the convenient direct comparison with perfect volume level matching right fromthe listening spot.
On the one hand the family similarity between both devices from Yokohama, whichwere even powered through identical mains cables, became obvious in the form of
exemplary openness and definition of even the most subtle tonal or dynamic facets.
But as a matter of fact, the DC-37 still played one nuance more homogeneously andwith more suppleness in the upper registers, therefore seeming more natural withvoices or strings by that notorius grain for which, as we all know, the die-hard listenerhas to dig deep into his pocket.
This result is not a matter of self-evidence since the DP-550 carries the same
“MDS++“ converter technology which this manufacturer has pursued and refined foryears and where Accuphase reduces distortions and noise by cascading several
converter ICs. And, of course, the analog output stages that feed the signal to one
pair of RCA and XLR connectors each, also bear a great deal of resemblance. But
while the DP-550 uses six 32-bit chips from ESS Technology per channel in its“Multiple Delta Sigma“ array, the DC-37 boasts eight of them, supposed to enhance
precision even further. Our laboratory reveals top-notch values.
Who, like the Japanese, fights for the third decimal place on the final centimeters,
mustn’t cut corners anywhere. Accordingly we find fully independent power supplies
for the digital and analog sections, and only selected components are usedthroughout.
In daily use, however, the reliable handling and operation are at least just as
essential. Apart from the fact that minor problems in the communication between
computers – be it a PC or a Mac – may arise anytime, the Accuphase got along
instantly with our notebook and Audirvana Plus. And those slightly bumpy phases in
between, when the Apple suddenly delivered reduced formats or fell totally silent,
may also be due to the circumstance that we kept reconfiguring it for our comparison
DACs. In any case, the DC-37 stayed receptive all the way.
By all means we were not slow on the line. Audioquest’s Diamond ensured optimum
data transport – just like in other digital connections, the cable grade is also a crucial
factor with USB for the achievable sound quality. And so we were feeding the newAccuphase with music formats, starting from 320 kbit MP3 to native PCM high-bit
files in 24/192, as can be found e.g. on the STEREO Hörtest Editions. With “doubleDSD“ files transfered via “DoP“ we went even further uphill. In the so-called “DSD
over PCM“ mode the single-bit data stream of the DSD format is sort of transmitted ina PCM envelope. Hereby the display sometimes jumped to 32 bit showing sample
rates beyond 300 kHz.
No surprise: everything great!
And this is how it’s supposed to be in daily use: Unlike before, when the only digitalsources were CD or DAT with the key figures 16/44.1 or 16/48 respectively, today
many listeners have their music archived in the most diverse formats on theircomputers or NAS harddisks, which the D/A converter has to adjust to automatically.
The Accuphase acted as a discreet butler, softly clicking at the most with formatchangeovers, only to be indicated on its display.
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At this point we don’t even try to pretend as if we were surprised at the DC-37’s
superb performance. Honestly speaking, we didn’t expect anything else. Thus themachine in shimmering champagne gold unfurled exquisite sound images from eachformat and with each musical style. Like on an impressionistic painting theAccuphase was dappling the opalescent sound hues and delicately fading reverbtails in “Play of the Waves“ from Claude Debussy’s “La Mer“. Almost floating
weightlessly, yet at the same time accurately fanned out and contoured, the lucid
orchestra piece was projected into the listening room.
How sensitively the D/A converter gets to work also became obvious by how clearly it
was separating the various resolutions contained on our first Hörtest Edition. In theminor formats below the ultimate 24/192 the musicians were moving closer together,always with less air around them and less shimmering of tonal shades.
Shortly afterwards CC Coletti’s “Rock And Roll“ of Edition Vol. III featuring tracks
from top label Chesky Records made it very clear that the DAC with its flawlessly
lacquered wood sides can also party real hard.
Of course, one could itemize dozens of examples for the DC-37’s class. Instead we’dlike to mention another two striking attributes. Soundwise it lies on the line followedby Accuphase for quite some time of blending an explicit resolution capacity with anever cozy, yet all the more authentic tonality. We greatly appreciate this trend.
Also top with CD format
When crosschecking with German high-class converters from Accustic Arts or MBL, it
was not so much the sovereign style in which the Japanese renders complex
structures or copes with loud voices. Other contenders similar in price and ambition
can do that as well. Its strong point lies in a very sharply contoured separation ofevents which creates an impressive spaciousness. This is well audible on CarolinNo’s crystal-clear “Still Waters Run Deep“ from the new Hörtest CD Vol.VIII or James
Taylor’s elderly “Here We Are“, this time, however, in the 2.8 megahertz DSD format.
Because in order to experience the blessings of the DC-37, you’ll need no high-bit
PCM or double-rate DSD. It will allow the discerning listener to rediscover his entire
CD collection. At the same time it fits seamlessly into the premium league ofAccuphase’s product range both soundwise and technically and might indeed
upgrade some of their inhouse players. When combined with one of those popular
home network bridge solutions, the multi-talent could even turn into a streamer.
Matthias Böde

SACD via HS-Link and LAN cable
Most hi-fi fans know: other than the CD data stream the digital DSD signal can’t betapped on the player. But the proprietary Accuphase connection between discplayers of this Japanese brand such as the DP-550 (top) and the DC-37 allows anexception from the strict rule. For this purpose both feature an “HS-Link“ socket (redframe, bottom), preferably linked by a CAT-7 LAN cable of the highest possible
quality. If now a purchased or home-burnt SACD is rotating in the player, the one-bit
stream may be passed on to the DC-37. This is exactly what we did, whereby theconnection was working instantly and running absolutely stable – not a self-evident
feature when dealing with music files and interfaces. With an SACD in the slot– HS3

Link also transmits CD data so that no extra digital cable between player and DAC isrequired – the approx. 2.8 megahertz and 1 bit of the DSD bitstream signal willappear in the display of the DC-37). Such a connection makes sense, for via the DC37 it sounds even better.

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