Weiss DAC1 Converter Review
by Dr. Frederick J. Bashour
Dufay Digital Music
Leverett, MA 01054
Introduction
The DAC1 is a top-of-the-line digital to analog converter from Daniel Weiss Engineering
of Switzerland. The version tested accepts inputs at 44.1, 48, 88.2, and 96
kHz., and double-samples data input at the lower sample rates via DSP to one of the
two higher ones, before subsequent 4x upsampling within its D/A chip. A Mk. II version
will be available by May, 2002 which includes a second AES receiver for dual-wire
176.4 and 192 kHz conversion, but is otherwise identical to the review sample.
General Overview
The Weiss DAC1 is both simple to use and extremely flexible in interfacing possibilities.
There are four inputs梩hree on XLR connectors and one on Toslink optical?
and each is selected by its own large lighted front panel pushbutton. Each of the three
AES/EBU XLR inputs is actively routed to a corresponding XLR digital output, producing
a 則hru?connection suitable for monitoring at multiple stages within a digital
studio setup, or other recording, monitoring, or routing possibilities. Three front panel
LEDs display input wordlength (1-16, 17-20, 21-24 bits).
The Weiss engineering philosophy of combining several signal reclocking
schemes has produced extremely high jitter attenuation, leading the firm to boast that
the DAC1 is virtually immune to jitter frequencies from fractions of a Hertz up to tens
of kHz. While earlier models of the DAC1 included a clock output on one pin of a rear
panel DB15 connector梕nabling the unit to be set to act as a clock master條ater units,
as well as the DAC1Mk.II, omit this feature, as no audible improvement was said to be
heard as a result of master clock operation. I was, unfortunately, unable to test this
feature on my review unit, but can state without reservation that I have never heard
cleaner sound from any DAC梬ith or without master clock mode.
Particular attention was paid to the analog output stage, designed with the aim
of keeping as uncompromised an audio signal path as possible. The unit抯 discrete
Class A outputs present an extremely low output impedance, but never showed a bit of
instability in driving various loads梚ncluding 50 meter cables with unbalanced termination?
in my studio. The output level can be switched between 刪igh?or 刲ow?
mode, and the symmetrical circuit can swing +27dBu.
Certain pins on the aforementioned rear-panel DB15 connector can accommodate
two external mono or one single stereo potentiometer for remote level control; other
pins can control source selection with LED illumination. The remote level control takes
place in the digital domain, and is properly dithered to avoid quantization artifacts.
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The DAC1 runs quite warm梕specially on the right side, and should be ventilated
adequately.
In Use
First the bad news, then the good news. When I received the unit, I didn抰 think I
liked its sound at all. Two months later, I purchased the review sample! What happened
during that time period involved a certain amount of 別ar-training?on my part,
and a re-evaluation of my monitoring system.
I have owned an extremely expensive so-called state-of-the-art audiophile DAC
since 1988梐 Wadia 2000梬hose hardware, firmware, and power supply had been
continually updated by Wadia throughout the late nineties. As I received newer pro
audio converters for review during the past several years, I always compared them to
my Wadia reference unit and, ultimately, found them all lacking in one or more subjective
parameters. The dCS 954 was the first unit I tested which gave my Wadia serious
competition but, for various reasons, I passed on its possible purchase.
When the DAC1 arrived for review, I was about to do an interesting 刬nternational
violin band?session for the United Nations here in Studio Dufay, so I quickly
patched it in and, during and after that three-day session, alternated between it and the
Wadia. The latter sounded warm and euphonically pleasant, while the Weiss sounded
bright, scratchy, and a bit 刾hasey.?I impulsively pronounced it inferior, and went on
to other matters.
A month later梩he morning after the first day of a week-long 96 kHz multi-track
session I was recording for Dorian桰 was playing my rough mixes at the studio and
was a bit underwhelmed by the sound from the Wadia. I idly flipped to the DAC1抯
position on my monitor selector, and my mouth fell wide open! Here was the sound I
had heard live on my Stax headphones and Dynaudio BM6As the evening before. I
switched back and forth between Wadia and Weiss and slowly realized that the Weiss?
sound was clear, warm, crisp, true, airy, open, relaxed梐ll the proper audiophile jargon,
while the Wadia抯 was closed, murky, boomy and veiled.
What was going on here? I continued to use the Weiss DAC1 as reference DAC
during that session (at which I was recording the early music 剆uper-group,?Fortune抯
Wheel, at Mount Holyoke College抯 Abbey Chapel), even to the extent of bringing it
along to substitute for the DAC section of the Apogee PSX-100 I was using as my
剅ough mix?A/D-D/A converter. Each time I listened to the Weiss unit, I liked it
more.
A few weeks later, after I had finished the first edit of that project, I had time to
revisit my U.N. violin recording. It had been a 剄uick and dirty?session, with recording,
mixing, and editing happening simultaneously. I went back to my original multitrack
master and listened to each stereo pair. Yikes! One of them did sound screechy
and, since my quick direct-to-analog mix did not incorporate any of the delay compensation
I always add when I have the luxury of mixing 刟fter the fact?within software, a
certain phasiness was definitely present.
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To make a long story short, I learned that the Weiss DAC1 is a true monitoring
tool. If something sounds wrong through it, it is wrong! And if a source sounds really
nice, then one should pat oneself on the back. I had apparently been monitoring for
many years with a DAC which tended to 刬mprove?(via sins of omission) many of its
sources and which梚n the final analysis梙ad been lying to me.
Conclusion
My experience with the Weiss DAC1 has taught me many valuable lessons about
audio and auditory perception. As I embark on my latest recording system upgrade (to
Merging Technologies?Pyramix and 192 kHz multi-track), I am extremely grateful that I
have finally found a stereo monitoring DAC which will 則ell it like it is?while still rewarding
me with a 刵ice?sound梐s long as I抳e done the footwork and presented it
with a good recording in the first place. Thus, the ball is back in my court!
Dr. Fred Bashour holds a Yale Ph.D. in Music Theory, and currently performs as a jazz pianist
and church organist, in addition to working as a classical music producer/engineer and consultant
to university music libraries on the digital storage of course listening materials. During the
past 25 years, he has received credits on hundreds of recordings released on over a dozen labels.
He is also a contributor to Audio Media.
