| Blue Circle Audio BC501 Digital
to Audio Converter |
| What a Difference a DAC Makes! |
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|
July 2007 |

The
Blues
A while back, fellow StereoTimer
and a good friend over the past twenty years,
Mike Wright, called and asked me if I would be
interested in doing a review of the Blue
Circle Audio BC501 digital-to-analog converter
(DAC). Not that my schedule doesn’t get a
little crowded from time to time, because it
does, but Mike, not wanting to be accused of
cornering the market on Blue Circle reviews
decided to share the wealth.
Normally I don’t like to take on projects
without having some knowledge of what I’m
getting into. But since I knew Mike’s taste I
felt confident that the BC501 review would be
an exercise that I would find interesting. I’m
sure Mike also remembered how I gushed over
the BC208 Mono Hybrid Amplifier that he
reviewed a couple of years ago. So I told him
I’d be thrilled to take on the BC501. Thrilled
is actually an understatement because before
Mike could hang up the phone I was in my car
headed out to the suburbs to pick that DAC up.
Blue Circle Audio has been around for quite a
while now and designer Gilbert Yeung has
received numerous accolades for his amplifiers
and preamplifiers. Now he has decided to build
a DAC because like most engineers, he felt
that he could build a better unit than what it
is currently available on the market.
Thoughtful design and rock solid construction
have always been hallmarks of Gilbert’s products.
But so too is his quirky sense of humor. After
all, this is the same guy who turned some
ladies pumps into a pair of monoblock
amplifiers.
In order to demonstrate the variety of
materials and colors that his products are
available in, he has built products using some
interesting color choices. He once sent Mike
an amplifier for review with a bright yellow
faceplate and red chassis. Mike aptly
nicknamed it the “Ronald McDonald” amp. It was
no different when I received the BC501, it was
pink … bright pink.
Despite the odd color choice, the BC501 is
17.25 inches wide, 3.75 inches high, 16 inches
deep, and was quite hefty to hold. In the
center of the faceplate is Gilbert’s signature
illuminated blue circle power indicator. To
the right is a selector switch for the three
inputs: single-ended (RCA), balanced (AES/EBU),
and ST fiber-optical. To the left are lights
for indicating phase inversion, de-emphasis,
and signal lock.
On the back are the three digital inputs that
I just mentioned plus two sets of analog
outputs: single-ended (RCA) and balanced (XLR).
Rounding out the rear panel connections is a
hospital grade power cord with a Neutrik
PowerCon twist-lock ac connector. Gilbert
feels that the Neutrik connector has better
connectivity and sounds better than the
popular IEC connector that is found on most
equipment. The BC501 does not have a power
switch so after I connected the digital out
cable from the Bel Canto CD-1, and ran the
analog outputs into the Bel Canto Pre3
preamplifier, “presto,” I was ready to go.
DAC’s
Incredible
I knew the BC501 had been broken in already
because it had just come back from an industry
trade show and Mike had already listened to it
for a while. So I wasted no time getting into
it. My first impressions of the unit were
fairly unremarkable. The Bel Canto CD player
is a fine unit on its own and I wasn’t sure if
the Blue Circle DAC had been an improvement.
But then I remembered Gilbert saying that
because the BC501 has such a massive power
supply that you needed to wait at least 24
hours before you could give it a serious
listen. So I throttled back on my enthusiasm
and waited ‘til the next evening before
resuming my evaluation.
The next night it was like the intro to the
song that made Dinah Washington famous:
“What a difference a day makes, twenty-four
little hours, brought the sun and the flowers
where there used to be rain…” Oh what a
difference! After the BC501 had a chance to
come up to full power this was one of the
better digital playback systems that I have
had a chance to experience this side of the
Accuphase DP-57/DP-67 and the BAT VK-D5SE. The
Accuphase players are known for their smooth,
soothing, natural rendering of voices and
excellent high frequency reproduction and the
VK-D5SE is recognized as being very musical,
with great soundstage and midrange textures.
The Bel Canto player with the BC501 combines
all of these attributes together.
Normally I start from the top end and work my
way down but I figured I would save the best
for last. Listening to upright bass players
such as the late great Ray Brown through the
BC501 was an enjoyable experience. Each note
was well defined, and on live recordings I was
presented with the illusion that Brown’s
fingers were still traversing strings. On
selections that featured electric bass players
like Stanley Clark or Marcus Miller, the lower
bass also had good detail and bloom but didn’t
seem to be as dynamic when using a standalone
CD player. This only occurred on a few
selections when the recovery time from start
to finish of each string pluck was slightly
blurred which made the presentation just
slightly on the rich side. Not a bad thing but
just something that I noticed.
The midrange had wonderful detail and singers
had a palpable presence that was outstanding.
If I didn’t know the unit was solid-state I
could easily have made the mistake of thinking
there were a couple of tubes inside, because
the performances were so rich and compelling.
The BC501 had a naturalness about it that
allowed me to take my mind off the recording
and I became awash in the joy of music.
However, the most enchanting feature about the
BC501 is its ability to reproduce high
frequency information. I was amazed at how
“analog-like” the top end was portrayed. There
weren’t any sounds that I would characterize
as “digital nasties,” that lean, thin, shrill
or metallic sound that is sometimes present if
not appropriately addressed. That certainly
wasn’t the case with the BC501 because it
exhibited one of the more relaxed and clear
top ends that I have heard.
Since I had gotten comfortable with this
marvelous piece, I called Gilbert and asked
him what was behind the BC501’s wonderful
sound. He told me it was a “24-bit, 8 times
BiCMOS sign-magnitude setup.” Dumbfounded, I
had to ask him just what the heck that meant?
He replied, “It plays music.” I couldn’t have
agreed more.
One
of the discs that I really like and find very
musical is Helen Merrill’s The Complete
Recordings with Clifford Brown [LONEHILLJAZZ
LHJ10164]. The track that I think is really
outstanding is the old Cole Porter number,
“You’d Be So Nice To Come Home To,” arranged
and conducted by the legendary Quincy Jones
with Clifford Brown on horn. This is an early
recording laid down in the mid fifties. Milt
Hinton is on bass and Osie Johnson plays drums
but tones it down some by using brushes
instead of the sticks. Jimmy Jones is in the
background on piano adding substance. With the
BC501 this older recording really came alive,
allowing me to enjoy it just as much as some
of the more contemporary recorded pieces. The
BC501 demonstrated a three-dimensional feel
and provided the appropriate spacing between
each of the performers. Mrs. Merrill voice
comes across with regal intimacy as though she
was so up close that she was grasping the mike
with both hands and singing without a care in
the world. When it was Mr. Brown’s turn on
trumpet he released a fire storm of notes that
had the bite and tenacity that he was often
known to produce.
Another
recording that I really enjoy listening to is
Hugh Masekela’s Hope [Triloka Records
KAT-2020-2]. In April of 2006, I was able to
hear him live at the Hot House club here in
Chicago. I was fortunate enough to have a
table in row two, near center. He performed a
bunch of my favorites but the highlight of the
evening was when he sang “Stimela.” This is a
sensitive song that deals with oppression and
the struggles in life. What made hearing this
song so magical through the BC501 was the
DAC’s remarkable transparency. Hugh Masekela’s
voice and trumpet has so much body and texture
that I was reminded of that sentimental
evening.
Finally, one of my litmus tests for a digital
system’s top end performance is Jessica
Williams’ Live at Yoshi’s Volume Two
[MAXJAZZMXJ214]. I haven’t been to Yoshi’s
since their move to Oakland, but I’ll probably
make the trek out to San Francisco fairly
soon. But in the meantime the last track,
“Summertime”, during the summertime will have
to do. The BC501 captured the delicate details
of simple brush strokes on the cymbals without
any coloration, and Jessica Williams on piano
is so romantic and charismatic with intimate
notes blissfully floating in the air that I
was in complete awe of the performance.
The Cure
I’m glad that Mike Wright asked me to take on
this review project because listening to music
using the BC501 was a real treat. This Blue
Circle DAC is the perfect cure for symptoms of
“digital irritability.” It helped to make my
music collection more enjoyable and eliminated
some of those digital anomalies that we all
find irritating, especially ill-defined or
somewhat bright treble information. So I would
certainly give the BC501 strong consideration
if you are looking to upgrade your digital
playback system. This is truly a wonderful
product and an outstanding performer.

Specifications:
* front panel:
selector switch / phase switch / signal lock,
phase invert, and de-emphasis indicators.
* three separate stages of power supply
regulation to isolate digital, digital/analog
and analog.
* hospital grade power cord with Neutrik
PowerCon twist-lock ac connector for NO loss
ac power transfer.
* over 110,000uF capacitance filtering ...
brown out proof.
* separate digital and analog power
transformers.
* custom designed ac filtering to eliminate
noise leaking into the ac line.
* automatic de-emphasis for 44.1, 48, 88.2,
and 96 kHz.
* THD+N = <0.0009% measured at -0 dBFS.
* inputs: (1) balanced - AES/EBU, (1) single
ended - RCA(standard) or optional BNC, (1) ST
Fiber-optical(standard) or optional Tos-Link.
* outputs: (1 pair) XLR-balanced, (1 pair)
RCA-single ended - low impedance
Manufacturer:
Blue Circle Audio
RR2
Innerkip, Ontario, Canada
N0J 1M0
Tel: +1 (519) 469-3215
Website:
www.bluecircle.com
Price: $4,095.00 USD

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