In our last issue, we published a review of the Blue Circle BC 3 preamplifier which
we had auditioned with a few power amps as well as the BC2 monoblocks. In this issue,
we are going to explore the merits of the BC2, connected with other preamplifiers
and a variety of loudspeakers, so we can determine the amplifiers' sonic disposition.
Before we get into the nitty gritty, here's a recap of the company's origin. Founded
several years ago by Gilbert Yeung, Blue Circle Audio Inc., manufactures and markets
amplifiers, a preamplifier and powerline conditioners rather successfully in Canada.
Recently, the company has also established an aggressive and successful export division
and things are happening quickly. We reviewed the preamplifier first, because our
Editor claims that it is much more difficult to come up with a good design. The plan
was that if the preamplifier passed our test, we'd review the amplifier.
The BC2s are radically different from most traditional amplifier designs. Housed
in handsome cabinets of oiled wood, the units have large heat sinks located on top
of the amplifiers (there is a reason and we'll tell you about it later on). Each
amp stands 16.2 inches high, with a depth of 25.5 inches and a width of 10.25 inches.
The massive heat sinks run the depth of the units creating the appearance of freehand-style,
industrial pieces of art--if this makes any sense. The company logo--a Blue Circle
of course--is back-lit with an incandescent light bulb. The front and side panels
below the heat sinks and the bases of the units are all finished in oiled wood. The
rear of the amps accommodate five-way, gold-plated binding posts, the RCA input and
the power connector.
First, let's talk about the heat sinks. They are located on top because the units
generate a lot of heat, which is best dispersed by allowing it to rise naturally.
The reason for the extreme heat development is the Class A operating circuit of the
amplifier. It's a hybrid power amplifier based on a single-ended common emitter stage
which means that the signal is managed by one active component in each stage. Transistor
output stages have been chosen and handle frequency ranges from DC to 60kHz. The
transistors used react quickly without phase error and are capable of 2MHz with unity
gain. However, they only have to handle 20kHz or 1% of their potential. The design
employs zero feedback--a system whereby crossover distortion is practically eliminated.
At the gain/input stage, a 6SN7 single Jan Philips vacuum-tube has been chosen the
achieve "headroom". This complements bipolar transistors in a circuit with no global
feedback and culminates in a unique design which is hand assembled. Cardas Quad Euteric
solder, RCAs, Holco 0.5% metal film resistors, Kimber Kaps, Jena Labs wire and point-to-point
wiring complement this no circuit board design. The wood exterior was chosen because
metal parts didn't sound good enough for Mr. Yeung--he listens to every amp which
leaves the factory. Finally, the BC2 comes up with 75 watts of Class A sound--good
sound as we shall see.
The BC2 doesn't sound like a typical tube amplifier, nor does it sound like a traditional
solid-state design. It does, however, sound rather musical. There are the sweet highs
of a good vacuum tube amp and the resolving quality of a fast solid-state amp, particularly
conspicuous in the bass region. Our tests were conducted with a pair of Meadow Song
Labs (electrostatic) speakers, a pair of Ethera Vitae speakers, the Ruarks and the
Polk speakers. Our panelist and columnist David McCallum also used the Blue Circle
components to drive a pair of Quad ESL 63s. Our initial listening test was with the
Polks. You may recall that the Polks are amplified to drive their subwoofers but
allow connection to other amps in a full-range mode or to drive only the mid-and-high
frequencies. This system configuration impressed all of our panelists, in fact it
was considered a match made in(audio) heaven. Exemplary highs, explicit mid-range
and excellent imaging were the highlights of this system. When we used the Polks
driven with the BC2s in the full-range mode, it became apparent that the bass information
matched the status of the amplifier's mid and high frequency performance. The bass
is full-bodied and very resolute down to bottom-end capability of the loudspeakers.
With the Meadow Song Labs, the BC2s fared almost as well. The MSLs can and will deliver
sophisticated high and mid-range information along with uncanny inner detail, provided
that the amplifiers can deliver as well. The Blue Circle amplifiers brought the MSLs'
inner detail proficiency out into the listening room, almost liberating the information.
The bass came across tight and powerful, yet controlled and resolved all across its
spectrum. The system sounded exquisitely musical, but we couldn't manage more than
100dBs sound-pressure levels (at five feet). That's enough to chase the cat out of
the listening room and to get the spouse to complain, but shy of earth-shaking volumes.
The Ethera Vitae speakers came alive with wonderful resolution and musicality and
provided complement to the BC2/BC3 combination. The Ruarks also made an outstanding
match, sounding warm and accomplished throughout the entire frequency range, missing
no subtleties known as inner detail. McCallum's Quads sounded convincingly lush with
the sort of revealing quality which draws listeners into the sound. David's comments
were all favorable, but his concluding statement was that the Blue Circle/Quad combination
was the best sound he has ever had in his listening room.
All loudspeakers sounded impressive and delivered an outstanding sound stage which
clearly rendered front-to-back information as well as precise boundaries. The only
downside is the amplifiers' rather medium power which doesn't allow it to drive very
Synopsis & Commentary:
The amplifiers are not an average design. Rather, they have been built to satisfy
the demanding music lover. These monoblocks will satisfy those who prefer to hear
music instead of the components. However, audiophiles who listen to components can't
nit pick the Blue Circle amplifiers. They may not agree with their sound quality,
because their criterion is another amplifier--one which they may favor for some reason.
However, when music is chosen as the yardstick by which to judge the Blue Circle
amplifiers' performance, we conclude that all instruments, voices and the sounds
they produce come across correctly--as good as it gets in modern audio. Granted,
there are certain drawbacks: the amplifiers get hot, the power isn't up there with
some of the big guns and there may be speakers that do not match well--although we
don't know which. In any event, the benefits far outweigh what must be considered
no more than potential disadvantages. The BC2s provide musical delights almost equal
to a live performance. The sonic sophistication, the handling of complex musical
passages and the resolving quality across the audible frequency spectrum elevates
these amplifiers not only into the high end, but also into the high-performance category.
The entertainment value of the Blue Circle amplifiers is outstanding, which is why
we believe that these amplifiers have been designed not as much for the tweak audiophile,
as for those who love music. These are a "must listen" for all those who have revealing
loudspeakers and are still looking for an amplifier.