Go to Home Page

Click here to go to Index for All Preamplifier Reviews

 

Product Review
 

Blue Circle BC3000 MKII Dual Mono Linestage Tube Preamplifier

February, 2005

Jason Victor Serinus

 

Specifications:

 

5 Line level inputs, 1 Loop Input (3 Line Level Inputs for
    Balanced Version)
2 Preamp Outputs, 1 Loop Output
Tube Complement: 2-6922 (Electro-Harmonix)
Hum: Below 400Hz: >-143dB or <1.5uV
Channel Separation: >107.5dB
● MFR: 10 Hz - 100 kHz ± 3 dB
Distortion at 1V Output: <0.05 %
Voltage Gain: 23.5 dB
Maximum Output: 25 Vrms
Volume Control Range: -95dB to 0db in 62 steps
Input Impedance: 100 kOhms
Output Impedance: 180 Ohms

Power Requirement: 120V 50/60Hz; 38 Watts
Dimensions: Main Chassis: 3.25" H x 17.5" W x 14.6" D;
    Power Supply: 5.4" H x 6" W x 14.6" D
Weight: Main Chassis: 37 Pounds; Power Supply: 16
    Pounds
MSRP: $6495 US for SE; $7095 US for Balanced

Blue Circle Audio
http://www.bluecircle.com

Introduction

Some may think that reviewing is a fun job. Not always, at least for this
critic. Occasionally, it is a matter of getting through a review of a product you don't like. But, it's another thing if you're reviewing a product as wonderful as the Blue Circle BC3000 MKII and find yourself wanting to listen more and more.

Auditioned in its single-ended (SE) configuration, which mates with my reference single-ended Jadis  Defy 7, Gilbert Yeung's Blue Circle BC3000 MKII
preamp is a joy to listen to. It certainly  qualifies as one of the two best preamps I have  so far had the privilege to review.

Allow me to qualify that statement. My current reference preamp is not a stand-alone unit; it is the one-piece Theta Generation VIII DAC-preamp. I have often wondered if the significantly shorter signal path of a one-piece combo contributes to its superiority.

While the listening I conducted for this review leaves me further convinced that the Theta is a superb preamp in and of itself, the different but superb sound of the Blue Circle BC30003 MKII suggests that a longer signal path need not necessarily degrade an audio signal.

When you use a stand-alone active preamp as good as the SE Blue Circle, you may in fact discover that it adds an extra and welcome musicality to the signal. Even if there is a slight loss on one level or another (all plugs and jacks can contribute to signal loss), the extra musical satisfaction it may deliver can more than compensate.

Take, for example, an inexpensive unit - say $299 - that has a DAC, preamp, and power amp all in one chassis. Will that bargain unit sound better than a more expensive outboard DAC, preamp, and power amplifier system housed in three separate chassis and connected by two sets of interconnects (DAC to preamp, preamp to power amp)? Most probably not. But only if all three components are high quality will the final signal to the speakers also be high quality. One poor component in a chain of three can seriously compromise the sound.

The same, of course, can be said of life in general. Few of us have "perfect" mates, friends, jobs, or sound systems. But when they make us happy, they make many of us so happy that their imperfections count for nil. That is the case with the Blue Circle BC3000 MKII Dual Mono Linestage Tube Preamp. When all is said and done, the sound of the single-ended version makes me feel fulfilled.

You can even select what kind of knobs you want. The photo below shows the various choices.

The Design

I'll leave most of the technical discussion to Blue Circle's website [http://www.bluecircle.com/index.php?menu_id=1770]. I do however include the following comments from Gilbert Yeung [with mild editing of grammar]. Gilbert's feedback on the difference between the sound of the single-ended Blue Circle BC3000 MKII I auditioned and the balanced version that I have not heard has a strong bearing on my conclusions.

When I wrote Gilbert, I noted that the balanced the BC3000 MKII only has balanced inputs and outputs; it does not have RCA jacks. I asked Gilbert if he had considered building a balanced preamp that offered both single-ended and balanced inputs and outputs. I also asked about the difference in sound between the SE and balanced versions.

“When I say balanced, I am saying a completely balanced system from CD player or turntable cartridge all the way to the speaker. If one were to mix and match, then it would be best to stay with SE (Single Ended).

 “When it is a completely balanced system, usually it will have a more defined soundstage. Bass also has tighter, better control. SE usually has a more holographic soundstage and tiny bit loss in the bass. Balanced usually has a more effortless presentation of music. There are other differences, and I can keep going on and on and on, but I believe the above are the biggest differences.

“For $100 additional, we can install a processor bypass loop for hooking up the BC3000MKII to a multi-channel system. When the user wants to listen to two channels only, he/she can just use the BC3000MKII. When the system is in multi-channel mode, flip the processor bypass loop switch, and the front two-channel signal will bypass the BC3000MKII and go right through to the power amp from the processor output.”

Rear panel of balanced version - not reviewed

I paired the Blue Circle with the solid-state Red Planet Labs STR201. I would have also tried it with my Jadis Defy 7 MkII amp were it not in the process of being replaced by the current Jadis Defy 7 Deluxe (review coming in a couple of months). However, pairing a tube preamp with A solid state power amp is frequently done, because it combines the sound of both tubes and transistors, and also supplies more power to the speakers than is generally available from tube power amplifiers. The Blue Circle costs twice as much as the amp, but the Red Planet amp offers outstanding value
for its price.
 

The Sound

I first auditioned the Blue Circle while reviewing a pre-release CD-R of jazz great Fred Hersch’s new Leaves of Grass (extended review coming in March). I normally don’t expect great sound from a CD-R that an artist whips together in their home. Imagine my surprise at discovering a recording so good that even the sound of a pre-release CR-R was light years ahead of many recordings from an earlier digital age.

I found the air of the Blue Circle beautiful and seductive. It was so delicious, and the percussion so clear, that I was reluctant to interrupt my listening by switching back and forth between Blue Circle and Theta. Nonetheless, I eventually roused myself. Each return to the Blue Circle further convinced me of its gifts. It offered a most musical glow. The Theta had an immediacy that at times was a bit scary (albeit never sterile). Its bass, a Theta strongpoint, also seemed a bit clearer and more impactful. But the romance and fullness of the Blue Circle proved irresistible.

As I continued to audition the Blue Circle with other recordings, a nagging question entered my mind. Is any preamp I review at a disadvantage when compared to the Theta, which combines a first rate DAC and preamp in one unit?

There was only one way to find out. I called my friend Jeff Wilson, a devoted member of the Bay Area Audiophile Society (BAAS). Jeff, who owns a 24-bit Audio Logic tube DAC, had previously contacted me to propose a DAC shootout as a BAAS event. He was confident that the Audio Logic would leave the Theta dead in the water.

I didn’t have a shootout in mind. But I did want to see how a stand-alone DAC feeding the Blue Circle preamp would compare to a one-piece DAC/preamp unit, in this case the Theta Gen. VIII, feeding the Blue Circle.

Jeff was gracious enough to make the Audio Logic available several days in advance, allowing ample time for setup and warm-up. When he showed up for extended listening, he brought with him an EMI disc of André Watts’ 1986 Liszt recordings. I immediately objected, fearing the disappointment of early digital sound.

My concerns were certainly justified while listening to the Audio Logic/Blue Circle combo. The sound was flat, lifeless, lacking in color, and irritating on high notes. I already knew that the problem couldn't lie with the Blue Circle, which had sounded wonderful on other CDs. Unless the Theta failed to make the Watts recording sound any better, it was clear that there was no point in listening further to the Audio Logic.

I thus proceeded to listen to the Watts CD using the Theta as a stand-alone DAC/preamp; the Blue Circle was temporarily removed from the chain. The Gen. VIII by itself produced more air, life, and presence than the Audio Logic/Blue Circle combo. The flatness heard from the Audio Logic was somewhat ameliorated, the bass cleaner and
more profound. It was clear that the Audio Logic was an inferior DAC, and would not prove of further use in the review process.

How would the SE Blue Circle sound fed by the Theta DAC? [Note: When the Theta is used solely as a DAC and feeds into an external preamp, its volume control simply functions the way any DAC's gain stage does. This is not a case of putting two preamps back to back in the chain.] The bass was a little less deep, but there was an added romantic warmth and air to the presentation that more than compensated. The Theta DAC/SE Blue Circle preamp combo did the best job of filling the space with something that sounded a step closer to real. André Watts' piano seemed more dynamic, and the highs finally started to ring in space (albeit still in an unsalvageable
irritating manner common to many early digital recordings).

Jeff liked the Theta DAC/SE Blue Circle combo the best. He praised the Blue Circle's extra (and natural) bloom and air in the midrange. He felt the preamp in the Theta stand-alone unit a little flatter sounding overall and lacking ultimate dimensionality and richness in the body of instruments. To him this registered as a lack of emotional involvement. I certainly heard what he was talking about, but the Theta's greater
immediacy, sonic neutrality, and fabled bass extension suited me emotionally to a T.

[Note. I recently spoke with John Baloff at Theta. John told me that when Theta designed the preamp section of the Gen. VIII, a few experienced evaluators complained that it lacked the midrange bloom of some other preamps on the market. Theta chose neither to beef up the Gen. VIII's midrange nor to overemphasize its bass; instead, they maintained its neutral sound.

Many audiophiles who are not accustomed to the sound of live, acoustic concerts often confuse the extra midrange bloom of some audiophile equipment for the real thing. It is not. It is extra midrange bloom. The same is true for extra deep, boomy bass, the kind often heard at amplified concerts. Nonetheless, if implemented properly, extra midrange bloom and/or bass emphasis in audiophile equipment may provide musical compensation for other deficiencies inherent in most reproduced sound].

Just as I began to articulate a number of qualities that I thought the Blue Circle lacked, Jeff asked me what kind of supports I was using under it. I blinked my eyes, looked again, and discovered to my everlasting shame [Serinus critics, take note] that while I was using the same Nordost Valhalla interconnects and power cables as in the rest of my system, I had failed to place supports under either the preamp or its power supply. Both were sitting directly on my equipment racks, with only their inadequate stock feet beneath them.

Some readers may ask “So what?” My response: countless hours spent comparing Ganymede, Stillpoint, Michael Green, and other support systems has convinced me that choice of equipment support can made a huge difference in the sound of a component, especially tube products, as they can be microphonic from mechanical vibrations.

Happily, I had two extra Ganymede ball-bearing supports available. Once installed, all my equipment was floated on Ganymedes.

“It’s like a different preamp!” Jeff exclaimed. And so it was. Almost the entire list of “less thans” that I had prepared to share with you was immediately rendered invalid. No point talking about differences that don’t exist.

After listening to two of my usual standbys,Rachmaninoff's Symphonic Dances (Reference Recordings) and Rosa Passos with Ron Carter (Chesky), I continued to find the sound of the stand alone Theta DAC/preamp a little more direct and natural, albeit less atmospheric and warm than the Theta DAC/SE Blue Circle preamp combo. Bass, on the other hand, was not only a little stronger with the one-piece Theta, but bass transients and pitches were also more pronounced and defined. Even though the Theta's preamp section may have offered more resolution, Jeff was swayed by the Blue Circle's greater depth and ingratiating sound.

Note however Gilbert Yeung's e-mail message, included above, which he wrote without any knowledge of my feelings about the SE Blue Circle's bass. The implication of Gilbert's comments is that the mild bass deficiency I experienced with the SE BC 3000 MKII may be much less, if non-existent, with the balanced version.

If Gilbert Yeung can spare his preamp long enough, I look forward to pairing it with the “in the mail” Jadis Defy Deluxe and adding additional commentary about that pairing to this review. Given that the Jadis offers many of the qualities Jeff admired in the Blue Circle, I wonder how the combo will sound and feel.

Mating the Blue Circle with Tube Amplification

Although I did not have my reference Jadis Defy 7 MKII on hand - it had just been sold, and the latest version, the Jadis Defy 7 Deluxe, had not yet arrived - the folks from deHavilland brought over their GM70 50W single-ended triode monoblocks for evaluation just as I was finishing this review.

When deHavilland designer Kara Chaffee took a first listen to her marvelous amps through my reference Theta Gen. VIII, she complained that the sound of Diana Krall's "When I Look in your Eyes" was not as rich as she had hoped. She especially pointed to the sound of the guitar in the second track, which she found flatter than she was accustomed to.

I immediately proposed that we route the Theta DAC into the SE Blue Circle BC3000 MKII to hear if it would make a significant difference. Did it ever! The guitar was noticeably fatter and richer sounding.

It became clear that when paired with tubed amplification that has significant midrange warmth and presence to begin with, the SE Blue Circle's tube bloom is further magnified. This was the sound that Kara had been accustomed to hearing. Regardless of whether or not it was more or less true-to-life than through the Theta's preamp, it was delicious. In fact, I would go as far as to say that, thanks in no small part to
the fabulous deHavilland amps (review forthcoming in April or May 2005), it was irresistible.

Conclusions

The SE Blue Circle BC3000 MKII preamp is a superb unit. It offers everything one might desire from tube preamp: a natural but never exaggerated or artificial sense of air, warmth, expansiveness, and musicality. Properly supported and isolated from vibration, its highs are as extended and clear as those from a top quality solid-state preamp. The SE version – the balanced version has not been auditioned for this review – may lack the last iota of bass extension and detail, but its overall musicality makes it a must-hear product.

Regardless of whether you can afford a preamp in this price range, giving it a proper listen should go a long way to convincing you that an extra financial investment can deliver enormous musical satisfaction. Even mated with an amp half its price, the Blue Circle’s flagship quality sings out in spades.



- Jason Victor Serinus -

Associated Equipment
Digital Front End
Sony 707ES transport modified by Alexander Peychev of APL Hi-Fi
Theta Gen Va single-ended DAC (to be replaced shortly by the Gen VIII)

Perpetual Technologies P-1A with Modwright modified Monolithic Power Supply and Revelation Audio umbilical power cable (not used for this review)

Amplification
Jadis Defy 7 Mk IV modified with a Siltech silver harness

Preamp
Bruce Moore Companion III tube preamp with Electro-Harmonix gold pin 6922s and Jan Philips 12AU7 equivalents;
Reflection Audio OM-1 Quantum battery-powered preamp in non-battery mode (used for this review)

Loudspeakers
Talon Khorus X speakers (with latest modifications and Bybee filters that render its response even across the spectrum and greatly improve the bass)

Cabling
Nordost Valhalla interconnects and digital interconnects
Nordost Valhalla bi-wired speaker cable
Powercables: Elrod EPS-1, 2, and 3 and EPS-2 and -3 Signature on main chain plus Harmonic Tech, Nordost, and AudioPrism SuperNatural S2 elsewhere

Accessories
PS Audio P600 Power Plant power synthesizer with MultiWave II
PS Audio Ultimate Outlet; PS Audio Power Ports
Michael Green Deluxe Ultrarack, Basic Racks, room treatment, and Audiopoints
Ganymede supports under amp and transport
Black Diamond Racing Cones
Shakti stones on Amp, Monolithic/P-1A and Theta
Bedini Quadra Beam Ultraclarifier
Audioprism Stoplight and latest, Marigo Stealth Mat for CDs
Sheffield/XLO degmagnetiser and break-in disc and Ayre demagnetizing disc

Analog (hardly the strong suit of the system, not used for review purposes)
Dual 1219
Sumiko Blue Point cartridge
Classe 6 phono preamp with optional umbilical cord
Interconnects: Tara Decade and Nirvana SL-1 to phono preamp

© Copyright 2005 Secrets of Home Theater & High Fidelity

Go to Table of Contents for this Issue

Go to Home Page

 

About Secrets

Register

Terms and Conditions of Use