February 1, 2010
Blue Circle Audio GDC
GoodSound! and its sister website SoundStage!
have offered a good deal of coverage of products from Gilbert Yeungs Blue Circle
Audio. The firm, based in Innerkip, Ontario, has a wide range of components, many in the
higher-priced bracket. But as Yeung states on www.bluecircle.com, neither he nor his fans were happy when Blue
Circle ceased production of its entry-level CS integrated amplifier. The CSs
successor is the GDC (starting at $1795 USD, depending on configuration).
Gilbert Yeungs philosophy is that its better to
spend money on a products sound than on its looks, and the GDCs appearance is,
unsurprisingly, stark. In fact, it looks a lot like Blue Circles BC707 and BC709
phono stages. If the GDC werent so slim (just 1.875" high), it would look good
in a system built for Darth Vader. The front panels flat black finish is broken only
by two knobs, for volume and input, a tiny chrome power switch, and, in the center, the
companys signature logo: a circle that lights up -- in blue, of course -- when power
The GDCs other dimensions are a standard 19"W x
14.5"D. The case is made of heavy steel, but its the massive toroidal power
transformer and other internal goodies that help the GDC tip the scales at 35 pounds. This
is one solidly built amp. Its claimed to output 95Wpc into 8 ohms or 140Wpc into 4
ohms, enough for most speakers and most rooms. The stated frequency response is
10Hz-25kHz, +0dB/-.1dB, at less than 0.25% THD (10W into 8 ohms). Noise is well down at
115dB vs. full power.
On the rear panel are: an IEC power connector with fuse;
one set of sturdy but plain speaker binding posts; three pairs of gold-plated RCA input
jacks; and a Ground Lift switch. This last is for use in case a ground-loop hum develops
between the GDC and another component; flipping the switch will break the ground loop and
stop the hum.
Blue Circle components are hand-built, and many options are
available with the GDC: a USB input with built-in D/A converter; an RF remote volume
control; JAFBP binding posts; a tape loop; a phono input featuring user-adjustable gain
(60dB or 38dB); control knobs of stainless steel or wood; and a stainless-steel faceplate.
The number of inputs can also be modified. Youd have to inquire for prices on these,
as they vary. My review sample was of the basic model, with three line-level inputs
labeled 1 through 3.
When the GDC first arrived, I was in the midst of reviewing
the Simaudio Moon CD.5 CD player and Moon i.5 integrated amplifier, so I used the Blue Circle
as a power amp for my office system: Sherwood CD-4050 CD player, Sangean HDT-1X AM/FM/HD
tuner, JVC F-Q41 turntable with Grado Green cartridge, and McIntosh Labs C27 preamp. The
GDC drove a pair of Celestion 3 speakers on Sanus wood stands, while the C27s
center-channel output was connected to the input of an Advent ASW 1200 subwoofer.
When Id completed the Simaudio reviews, I moved the
GDC downstairs to my main system, which hasnt changed much recently; the primary
source components are still a Dual CS5000 turntable with Shure M97xe cartridge and a Sony
CDP-303ES CD player. Normally, these are connected to my Linn Majik 1P integrated amp,
which drives my main speakers, a pair of NEAR 50Me IIs. In this instance, however, I
connected the Sony CD player directly to the GDC with Linn cables and used the Majik only
as a phono stage, connecting its preamp output to one pair of inputs on the GDC with
Dayton Audio interconnects. Then, just as I was settling in to do some serious listening,
I received a pair of Acoustic Energy Radiance 3 floorstanding speakers (review
forthcoming), and added them to the mix.
I connected the Blue Circle to the speakers with 14-gauge
AR cable. Because the GDC has only single speaker outputs, both the NEARs and the AEs were
single-wired, though each can be biwired. AC power is supplied by a dedicated circuit
feeding a PS Audio Soloist in-wall power conditioner and surge suppressor. My listening
room is 17L x 11W x 7H, finished in drywall (with makeshift wall
treatments) and floored with cork, most of the latter covered by a 9 x 12 rug.
Both sets of speakers were about 6 apart, 25 to 26" from the front wall, at
least 2 from any sidewall, and 6 from my chair. The NEARs fired straight
ahead; the Radiance 3s were toed in about 10 degrees.
British reviewers often speak of "pace, rhythm, and
timing." But I subscribe more to the words of the cofounder and, for many years,
guiding light of Jaguar Cars, the late Sir William Lyons, who described Jaguars as being
imbued with "pace, grace, and space."
The same could be said of the Blue Circle GDC -- and to
"pace, grace, and space" I add "bass." From the very beginning of my
listening, I was struck greatly by the pace of this amp: timing sounded absolutely right,
from the bottom of the frequency range to the top. For instance, the line on the
five-string bass that figures prominently in Fourplays "Baja Run," from Fourplay
(CD, Warner Bros. 26656-2), sounded extremely tight and strong through the GDC. In
"Corner Pocket," a great track from Count Basies Finest Hour (CD,
Verve 314 589 637-2), the infinitesimal but noticeable lag of the horns and winds behind
the rhythm section was crystal clear; there was no doubt.
Voices, too, sounded exceptional, and were the first
indication of the GDCs "grace": mids and highs were reproduced with
incredible detail. I was particularly struck by the reproduction of voices in Manhattan
Transfers version of Weather Reports "Birdland," from Down in
Birdland: The Manhattan Transfer Anthology (CD, Rhino/Atlantic D200146). Many mixing
tricks are used in this track, including the panning of singers voices all over the
soundstage. Through the GDC, each voice, no matter where placed, was rock-solid and pure.
Another example was the mandolin accompaniment on Bruce Hornsby and the Ranges
"Mandolin Rain," from The Way It Is (CD, RCA PCD-5904). The mandolin
comes in near the end, and is mixed to stand out from the other instruments and
Hornsbys voice -- but until the GDC, Id never heard it reproduced so clearly
Then there was "space": The GDCs
soundstages were superior in width and depth to those thrown by any other amp Ive
heard in years. Logically, this shouldnt happen; the reproductions of music by
well-designed amplifiers should be pretty indistinguishable from one another. But the GDC
was better. I pulled up a favorite, "Money for Nothing," from Dire Straits
Brothers in Arms (CD, Warner Bros. 47773-2). Through some systems this track can
sound fairly flat, the drums smooshed up against Mark Knopflers voice and lead
guitar. Through the GDC, however, the soundstage was high, wide, and handsome. The drums
were well behind Knopfler, the accompanying instruments well off to the sides, and
Stings "I want my . . .," etc., up and to the right. It was
a very revealing performance.
Finally, there was the bass. To quote the Who, the GDC
produced bass lines that were meaty, beaty, big and bouncy. That modest-looking enclosure
was hiding a lot of solid low-end impact. And the bass aligned with all four of the
qualities mentioned in that album title. Fulfilling characteristics meaty and big,
bass was solid and upfront; as for beaty and bouncy, its rhythm was
Its always a major delight to hear the bass line in
Fourplays "Baja Run" reproduced by a good system, but the GDC offered a
little something more: not more bass per se, but better-defined bass -- very
precise bass that dug deep. Another great example was the bass line in the title track of
Steve Winwoods Roll With It (CD, Virgin V2 90946), which gets up and boogies
hard. The GDC reproduced it with no sense of strain; it just did its job and got out of
the way. I like that in an amp.
And speaking of strain: Although the NEAR and the AE
speakers present a power amp with fairly complex loads at certain low frequencies,
throughout my listening the GDC never became more than slightly warm.
In a long-ago review for another publication of my
reference amp, the Linn Majik 1P, I noted that it was the first product Id heard
that could approximate the prototypical ultimate amplifier: a straight wire with gain. To
some degree, the Blue Circle GDC surpassed the Linn in this regard. Most likely it was the
GDCs lack of strain in reproducing high sound-pressure levels (the GDC puts out
95Wpc to the Linns 33Wpc). The Majiks pacing equaled the GDCs, but the
Blue Circle surpassed the Linn in grace, space, and bass. However, the GDC couldnt
ameliorate my main complaint about the NEARs: their over-the-top midrange. The GDC
reproduced the signal faithfully. And that is its greatest strength.
I really enjoyed having Blue Circle Audios GDC in my
system. Ive had the great good fortune to hear a number of really competent
amplifiers in the last year or so, from Rotel, Marantz, and Simaudio. As good as all of
them were -- and they were fine -- in the GDC Gilbert Yeung has created an amp that
compares well with or even surpasses all of them. The GDC has a great blend of power and
sound, and it can drive most speakers to which it might be matched with no problem. The
basic model is a bit shy of inputs, but that can be addressed by Blue Circle. If
youre into the game of "my amp is bigger than your amp," the GDC will come
up a bit short -- put it in an equipment rack and you probably wont even notice it.
But if your priority is fine, solid, realistic sound, the Blue Circle GDC is just the
. . . Thom Moon
Blue Circle Audio GDC Integrated Amplifier
Price: $1795 USD (base price).
Warranty: Three years parts and labor.
Blue Circle Audio, Inc.
Innerkip, Ontario N0J 1M0
Phone: (519) 469-3215
Fax: (519) 469-3782