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Bel Canto DAC2
Half-Size 24-bit/192kHz Upsampling D-to-A Converter
With major improvements in the basic processor chips
resulting in much better sound from entry-level CD and DVD players, plus a
number of super high-end all-in-one-expensive-box CD players such as the
$20K Linn, it was beginning to appear that separate outboard DACs would
become as unpopular as separate FM tuners or cassette decks. Yet there now
seem to be more new models available than ever before - something like the
explosion of outboard phono preamps (we’ll cover another next month).
However, in that case nearly all preamps and preamp/processors stopped
including phono stages some time ago, but transport-only players for CD are
few in number and for DVD almost non-existent.
The best DAC deals appear to be in the $1,000 to $1,500 range. Many cost
conscious audio buffs seek to come close to the sonics of one of the mega
cost CD players by purchasing such a DAC and mating it with an inexpensive
discount-outlet DVD player. With the SACD/DVD-A format war going on, the
dearth of truly universal players handling both formats, and the higher cost
of the new discs, the majority of audiophiles just want to upgrade the
playback of their standard CD collection. They would be pleased to move
their CD playback even partway up the sonic scale toward the realm of the
best of the new hi-res formats. Since many of the least expensive DVD -V
players are now including such features as progressive scan, DVD-Audio and
even HDCD, the prospect becomes even more attractive. Another attraction of
the newer outboard DACs is the upsampling feature. On first view the whole
idea of artificially ramping up the too-low 44.1K sampling rate of standard
CDs in order to bring the sonics closer to the transparency of purpose-made
DSD or 96-to-192K digital seems pie-in-the-sky. However the cost-no-object
dCs units have proved that you can - to some degree - actually make a silk
purse out of a sow’s ear! Unfortunately, none of the less costly
upsampling approaches thus far have equaled the often amazing results on
some standard CDs with the dCs upsampling processors, but several of them
achieve considerably higher fidelity goals than the previous generation of
non upsampling DACs. The DAC2 from Bel Canto is easily one of those.
Design
Bel Canto’s previous processor, the DAC1, was well-received but didn’t
include upsampling. The DAC2 features 24-bit/192kHz upsampling with a dual
differential, multi-bit delta-sigma converter combined with a low noise, low
distortion and fast “True Differential Current to Voltage” circuit (TDIV).
A major advantage of the upsampling approach is to avoid time smearing of
transient information due to the brick wall high-freq. filters of past DACs.
Bel Canto uses a 96K slow rolloff filter in the effort to improve transient
fidelity. The Asynchronous Sample Rate Converter offers a 20dB improvement
over previous SRCs.
Dynamic range is 117dB. Critical analog resistors are 0.1% metal-film devices. A clear path for the important analog output (where most in-player DACs cut corners) is provided by a simple 2nd order analog low-pass output filter. The board design of the DAC2 uses four separate layers to ensure optimum operating environments for the circuitry - which includes multiple stages of both digital and analog power regulation with separate toroidal transformers. Both RCA and Toslink digital inputs are provided on the DAC2. It employs the latest SPDIF receiver technology and a dual PLL reference clock recovery scheme using both analog and FIFO-based digital phase-lock circuitry for the lowest possible jitter performance. A local crystal oscillator drives the DAC directly.
Setup
Is simple. The compact size of the DAC2 is perfect for fitting in next to
any 17-inch-wide or less component - such as the DVD player itself - without
having to resort to a separate shelf. The Digital In jacks are on the front
of the unit, with a push-in switch to select either the coaxial or Toslink.
You can use a very short digital cable if the unit is next to the player.
With the jack at the front, if you have more than, say, a pair of digital
sources (one coax and the other Toslink) you can access the DAC2 easily to
plug in your PVR, computer audio output, DAT, or what have you. (Using a
Switchcraft mechanical switch for this would not be a good idea with digital
datastreams.) The rear of the unit has the usual pair of output jacks, and
you can use a detachable upgrade AC cord if you wish.
The Sound
I auditioned the DAC2 - after thorough break in - with an Integra 7.2 DVD A
player, Toshiba SD5700 DVD-A player, and my highly ModWright-modified Sony
9000ES SACD/DVD player. Among my source materials were my favorite 44.1kHz
samplers, the gold Opus 3 Testrecords 1, 2, & 3 and Test CD 5. I also used the new Paqauito D’Rivera MCDjazz CD
Brazilian Dreams and the Reference Recordings CD by the Minnesota Orchestra and
Eiji Oue, Reveries.
Both the Test CD5 and Reference Recordings discs were HDCD-encoded, but only
the Toshiba player had HDCD decoding built in. The differences between the
un-decoded HDCD and the decoded were subtle but definitely hearable,
especially on good headphones. There was a lowering of the noise floor,
greater transparency and improved dynamic range. On both standard CDs and
DVD-As, the two DVD-A players sounded almost identical, but on the HDCD
sources the Toshiba clearly pulled out ahead sonically with a much more
involving and musical recreation of the original recordings.
The playback bypassing the DAC2 of either of the DVD-A players vs. playback
with the DAC in the circuit was in many ways similar to the improvement of
proper HDCD encode/decode only more pronounced and with noticeable
enhancement of some qualities that didn’t occur with HDCD. Transient
response, for one. There was more impact, slam, physical feeling of peak
sounds on the instruments with the DAC2 on all of the recordings. So the
hype about extremely low jitter appears not be just hype. I should also
mention that I was using a pair of Monarchy SuperDrive jitter filters in
series in front of my previous DAC - one made a hearable improvement in
transient response and two even better. I tried the same tweak out of the
Integra player’s digital out and then into the DAC2; this involved a lot
of various digital cables, some with BNC connectors. Sorry to come up with
that rarely-heard audiophile reaction of not hearing a bit of difference,
but that’s the case here. So the jitter-control of the DAC2 must be
exceptionally well done.
There was also a smoother and (though I hate to use this hackneyed
audiophile term) more musical presentation throughout. The Toshiba was fired
up right out of the box without any break in, and sounded frankly a big edgy
out of its analog outputs without the DAC2. The DAC2 mellowed it out while
improving transparency and widening the dynamic range. There was also
stronger subwoofer-level bass.
The initial track of the Minnesota Orchestra disc - a Satie Gymnopedie -
sounded terrific with the proper HDCD decoding but out of the Toshiba’s
analog jacks. Putting the digital out to the DAC2 brought up more strength
in the two-note ostinato that continues thru the piece, made the solo
instruments stand out more from the body of the orchestra, and provided more
front-to-back depth to the string section. Those repeated two notes sounded
pretty much the same direct from analog, but thru the DAC2 the subtle
different timbre of each note became more prominent. On the D’Rivera disc,
with solo voice and backup vocal group, the solo singer was brought out more
to the front using the DAC2, and the backup voices - which has sounded
flattened out before - had a more three-dimensional depth to them.
I was checking something else and ran the Integra player for a time into the
audio inputs of my Pioneer RPTV’s built-in speakers. While all right for
standard telecast sound, these speakers are muffled and opaque to the max
for music playback. On a lark I did a comparison of the analog feed vs. Thru
the DAC2. I was surprised to hear a readily identifiable improvement even
thru that sonic bottleneck. There was more snap, greater bass extension, a
more musical sound and generally less fatiguing presentation of the players
on the stereo stage.
The second track on the Opus 3 compendium sampler is one of my favorites. It
is an arrangement of a tuneful Telemann violin concerto for a guitar quartet
and beautifully shows up soundstaging, depth, transients and dynamics. Thru
my Celestion L & R front speakers the DAC2 provided much more impactful
transients in the initial pluck of the strings, a wider soundstage and
generally more transparency. On the second Opus 3 sampler - which I compared
using headphones - there is an Eric Bibb song with vocal backup. The Bel
Canto made his voice more... well, bel canto - and the backup singers took
on more of a presence, clarity and depth. A later track on this disc - also
HDCD-encoded - is a slow, subtle buildup of various guitar sounds and
percussion. Without the DAC it sounded almost annoying - like a couple guys
fooling around in the studio. With the DAC2 the spatiality as well as
various timbral contrasts in the instruments stood out in bold relief and it
became a very imaginative bit of exotic tone-painting. Lastly, a track on
the sampler from the great Opus 3 B3 CD The Hammond Connection really
brought out the increased bass-end slam of the DAC2 vs. the analog outputs.
My Sony 9000ES player has had most of the major mods carried out by Dan
Wright at ModWright, with the exception of cryogenic-treated components and
interior-mounted Shakti Onlines. I plan to add some other tweaks (including
Shaktis) in my final installation of the player and will also route its
analog outs thru my Taddeo Digital Antidote. But I did some A/B comparisons
as it now is, with and without the DAC2. I found most of the DAC2 upsampling
enhancements listed above were evident, but to a much more subtle degree. A
somewhat more musical presentation is the best description I could come up
with.
Summary
The Bel Canto has my vote as a viable choice in a moderately-priced DAC. I
haven’t tried the Musical Fidelity or Birdland units, about which I’ve
also heard good reports. My advice is to try before you buy if you can. Take
a couple of your fave CDs and make sure the transport being used is similar
to what you have (or take yours along too). For those who already own a Bel
Canto DAC1, the firm can upgrade your unit. Just call their number at the
head of this review for details.
- John Sunier
Specifications
Up-sample Rate: 192kHz
Bit Depth: 16- to 24-Bit
Signal to Noise Ratio: >117dB "A Weighted"
Dynamic Range: 117dB
THD (Distortion): <0.003%
Frequency Response: 2Hz to 80kHz (-3dB)
Output: Stereo Pair RCA
Input Options: S/PDIF (RCA Type), S/PDIF (Toslink)
Output Impedance: 20 ohms
Output Level: 2Vrms Fixed
Power Requirements: 115/230 VAC; 50-60 Hz 10 watts
Size: 3.6 x 3.6 x 9 (HxWxD in inches)
Weight: 4 lbs.
Price: $1,500
Company Information
Bel Canto Design Ltd.
212 Third Ave. North
Suite 345
Minneapolis, MN 55401
Voice: (612) 317-4550
E-mail: mmccormick@belcantodesign.com
Website: www.belcantodesign.com
