Blue Circle


Gilbert Yeung of Blue Circle                                    (Copyright Soundstage, Inc.)

A great many audio designers seem to forget that they are supposed to re-produce music,  NOT re-produce sound. There is a big difference between music and sound. If we, as designers, don’t understand the difference and interpret it correctly, the end result is going to be awful. G.Yeung

Listening to Blue Circle equipment reminds us that simply capturing all of the information on a recording is not enough. As impressive as that can be, it is far too modest a goal. From the listener’s point of view, an accurate rendering of a recording is seldom an accurate rendering of a musical performance, though we often try to persuade ourselves that it is. Audio technicians would love it to be that straightforward, but it is not. Anymore than a high resolution photograph gets the essence of its subject. How to turn even a superb recording into music remains a challenge that begins when the pure technician leaves the room.

Gilbert Yeung of Blue Circle is among a select few audio designers who understand this. We hear it immediately when we hear our first Blue Circle amplifier driving a pair of — in my house — JMR speakers. Our very first response is not how accurate this recreation of a recording is, how impressive the verisimilitude; but how wonderful the music is. We respond first with our emotions, which is what Blue Circle addresses. The brain follows in due course — Yeung is a brilliant technician — but it is our feelings that pick up the first wave of sound: Yeung’s designs send the information through the emotions to the brain.

The key to the ‘Blue Circle Sound,’ from the early Class A hybrids on up the current solid state gear, has been Yeung’s unique kind of technical & intuitive genius that enables him to capture the complete package, the information and the emotion, with hardware.

Gilbert Yeung’s quest to reproduce the emotional essence of ‘live’ music has yielded some of the most satisfying preamplifiers and amplifiers in the world.

Amherst Audio began with Blue Circle. The zig-zag that got me to this line of preamps and amps followed one of the predictable routes: zig from Krell to Conrad Johnson, zag halfway back to Plinius. It could just as well have zigged from Bryston to Cary and zagged halfback to Plinius. To my ears, Blue Circle, especially in its current designs, comes remarkably close to achieving the mean between an accurate version of what’s on recordings and a presentation of what ‘live’ music really sounds and feels like. There are stars in the line – the O22i and new 002i solid state integrated amplifiers, the MKII versions of the classic BC3 series tubed preamps and new solid state BC107 (with optional phono stage!), the new ‘N’ series: BC1022, NSP, and NSL solid state power amps. But I have yet to hear any Blue Circle component that does not have a musical point to make. Especially when paired with JM Reynaud speakers, they are dynamic, weighty, and present. Interestingly, Reynaud and Blue Circle have moved in the same direction in recent years. Both understand that emotion is at the center of accurate music reproduction.


For full and more objective descriptions of Gilbert Yeung’s line of electronics, see the company’s web site: . What follows is my subjective opinions of a selection. All Blue Circle products are available through Amherst Audio.


BC 3 Despina II.

 Tubed, single-ended. The “original” Blue Circle preamp, upgraded to MK II status, which tightens its low end and adds dynamics, reflecting its designer’s move toward more incisive, bolder, and somewhat faster reproduction. Retains enough of the classic Despina sensuousness and remarkable midrange clarity to keep the BC3 faithful in the fold. The BC Despina II, Galatea II, and BC3000 II make excellent mates for cooler solid state amps. The Despina II is available in balanced topology for an additional $750. The BC 3 Despina is at the heart of many fine music systems. Price: $4945.

BC 3 Galatea II.

Tubed, single-ended. The upgrade from Despina II to the Galatea II, which amounts to the substitution of the 3.1 II for the 3.0 II external power supply, takes this extremely popular preamp a significant step forward. Bigger power supply means better bass and a bit more refinement through the midrange. The Galatea II is available in balanced topology for an additional $750. List price: $6395.

BC 3000 II.

Tubed, single-ended. The 3000 II represents a huge sonic upgrade from the Galatea II. When it is coupled with the optional GZpz power supply, it gets more refined and picks up an astonishing sense of ease on large orchestral and big band music. The BC 3000 GZpz was the best of the BC preamp line I’d heard until I heard the 107 solid state preamp. Those who prefer tubes in their preamps are likely to consider it unchallenged yet. List price for stock 3000 II: $8795. With GzPZ power supply: $10,995. The BC3000 II is also available in balanced topology for an additional $750.

BC 107. 

Designed especially to mate with Blue Circle’s new solid state amplifiers, the BC1022 and NSP in particular, the BC107 benefits in this role by sharing some of the N amps’ technology. In my house, coupling it with an NSP makes the excellent NSP an even better NSP: a more coherent and balanced sounding amp than it is on any other preamp I’ve tried it on, including the very fine Crimson 710 which I’ve been using as I awaited my BC107. The 710 has a different sonic agenda, namely feeding the very fast, 175 watt Crimson 640.

On Gonzalo Rubalcaba’s Solo piano album, the piano has more low end authority on the NSP with the 107 than it has had without it. Actually, the NSP’s low end with the BC107 has a lot of the weight of the 1022 and O22i but more clarity. The weight is less noticeable than it is on the 1022 and O22i because it’s part of a whole picture that contains the midrange and treble clarity and detail the amp revealed with the Crimson preamp. With the BC107, the NSP is a more complete sounding amp than it was, full of both feeling and musical information. The superiority one would expect it to have over the 1022 (and O22i) is now complete and evident, whereas before it was only partial. We are talking about a $15,000 package vs. a $7,500 one, so it should sound better. But in audio, things are not always that simple. Some may, for example, prefer the O22i’s and 1022’s hint of sweetness and emotional simplicity and directness. The O22i’s presentation is more intense; the 107/NSP’s more extensive, full of a variety of fascinating instrumental flavors! The distinction I make below between the O22i and NSP holds even more when the NSP is coupled with the BC 107.

The BC107 can be ordered with a very fine optional phono stage, an adapted version of the BC L’il 703. The BC107PH, playing with my Audio Note TT2 Deluxe with external power supply, an Arm 3/Vx, and an IO1 moving coil cartridge sounds…analogue. Meaning it conveys what Audio Note’s Peter Qvortrup calls ‘the medium,’ a sense of the physical aspect of musical instruments. It is not artificially and conspicuously warm, like some phono stages I have known; it is realistically and compellingly warm. When Starker’s cello shrieks in the Kodaly solo Cello Sonata, we hear a shriek but it a full-blooded shriek. I don’t remember very well what my BC703 sounded like, but the L’il 703 as implemented in this preamplifier sounds close enough to what I remember of the full 703 that it should keep you from feeling you’ll be losing much in moving to the L’il 703, at least in the form it takes in the BC107PH. Price: $4695. With optional phono stage and external power supply that serves both preamp and phono stage, $6850.

BC 307.

User controlled 6922 based, 6SN7 based, and solid state circuitry all in parallel with L3 power supply. A favorite among many Blue Circle fans for his reputed overall excellence and flexibility. I have not heard this preamp so I refer you to the Blue Circle website for description and review. and $11.950.


The NSC solid state preamplifier arrived in the summer of 2016 to be the ideal mate for the NSL: to realize all of the potential of that extraordinary amplifier. It is a considerably enhanced BC107 (many internal upgrades, larger chassis, much larger external power supply). It also implements the new DCRN (Direct Current Rails Network) power supply network, technology conceived to address the chief weakness of preamp/amp combinations: that the two units use their own power supplies, totally separate from each other. According to Gilbert, ideally what is wanted is some way to tie these separate power supplies together, “so that they are seeing the same picture at the same time — so they are working as one.”

Coming to the NSC from a BC107, we are immediately struck by its greater overall authority: we get a significantly weightier, fuller, richer, and more dynamic presentation — with all of the 107’s clarity but in a more rounded form. The NSC actually has the ability to make the truly fine 107 sound like a lightweight! Definition is comparable but has greater dimension, instruments have more of their distinctive color and substance. There is absolutely no loss of the 107/NSL combo’s characteristic tactile grasp of surfaces, the NSC/NSL simply delivers them with more depth and backbone: woodwinds have more wood in them, brass have more balls. And there is no loss of refinement: rather, the refinement seems more an integral part of the whole presentation. Bottom line: the NSL driven by an NSC with its DCRN network feels more forcefully present. As good as the NSL is on a BC107 — it was this combo that got me to order an NSL in the first place — we really don’t know how good that amp is until we hear it with an NSC.

We are told the NSC with or without its DCRN network  (Blue Circle can retrofit any BC solid state amp for use with the DCRN) can be used with any solid state amplifier.

The NSC is available with an optional phono stage that in terms of performance approaches that of the standalone BC 703. Price: $10,000. With phono stage: $15,000.

Integrated Amplifiers

Blue Circle has trimmed its integrated amplifier line to two solid state models, the O22i and 002i, which is a lower powered version of the 022i with its own distinctive voice. The class D integrateds are no longer in production. There is also a sophisticated new N series integrated coming in late 2018, to be called the NSi. It will be, in effect, a Super 002i-EPS incorporating a version of the NSC and “other enhancements.”


O22i with external power supply in optional curly maple and walnut faceplate.
O22i with external power supply in optional curly maple and walnut faceplate.


The O22i is a 125 watt (160 into 4 ohms) all solid state integrated based on the BC1022 stereo power amp. It was obvious that once we’d heard the BC1022, something on this order would have to follow.  It is one of the most comforting, satisfying, and commanding new products to emerge from Gilbert’s garage since the new “N” series stereo amps.

It is clear and commanding in an entirely natural way. Its chief virtues are (1) a sense of scale (large), mainly the result of a robust bass foundation, reminding us how essential really good bass is in conveying music realistically; (2) an almost magically silent background that makes possible an appealing kind of clarity; (3) body, which is not the same as bass, giving everything a sense of exciting physical presence; and (4) beauty, mainly the savory (meaty?) midrange but there is also a lovely sweetness to the highs. I would say the most conspicuous of these is body: pianos have body, low brass have rich clear authority, singers have chests!

I consider the O22i along with its new little brother, the 002i (see below), statement products, the best integrated amps Gilbert Yeung has designed. They are the amps I’d hoped for but was reluctant to expect and they complement each other perfectly. $7500

Great new review of the O22i on Positive Feedback.



002i with optional EPS power supply and dark walnut faceplates

Pictured above is the new Class A/B 002i 80 watt integrated, essentially to replace the FtTH2.

In its standard form, it has a beautiful sound, more noticeably beautiful than its big brother, the 022i. It is less robust and lighter, which creates a sense of greater subtlety, more delicacy. It is a trifle (pleasantly) indulgent. There is plenty of body to the sound when it’s called for — left hand of piano suddenly coming in alongside a cello. But body and weight are not the chief impression we get. What we hear first is beauty. This amp feels more like a cousin of the NSL than of an 022i. And it has the sound of delight in it:  “When I designed the 002i, I said I wanted to bring back the joy of the 80’s when most people were listening to the music and enjoying it.”

Blue Circle has also made available as an add-on option an external power supply called the EPS. With the power supply hooked up to the 002i, the augmented amp is dramatically more impressive, audibly a whole other amplifier. It sounds firmer, more forceful, vigorous, faster, firmer, more energetic, tighter — and more refined.  There is more evident control, edges are clearer & better defined: the overall presentation has a sharper but also subtler focus. Without the EPS, the 002i is softer, ‘romantic,’ easeful. With the EPS, beauty is no longer the amp’s most conspicuous quality…or rather the beauty has more backbone.

As my 002i has settled in, I find I am now playing it all of the time with the EPS, as is my first 002i customer. On truly critical speakers, like my new Jean Marie Reynaud Abscissa Jubilees, the body, mid-range clarity, and beauty of the 002i – EPS are extraordinary. As good as the 002i alone is on more modest speakers, I now feel that the EPS makes it twice as good. On Penderecki concertos (flute, horn, clarinet), the solo instruments are dramatically real and present, the double bass and low brass are both solid and clear. I’ll have to say I’m finding its modest 80 watts sometimes sound more powerful than my 022i’s 120 watts; and the amp itself, for those who crave refinement, clarity, and natural weight, even better. I did not expect that. The o22i has the 1022’s beefy voice, and many have to have that, along with its deeply saturated tonal colors. But the 002i – EPS is definitely the more refined amplifier of the two. It really does bring to mind the NSC/NSL sound for those with 80% fewer dollars.

There will likely be some people who start out with the 002i alone and come to like it as it is and may not like the added forcefulness and clearer focus introduced by the EPS, preferring the stand alone amp’s slight softness, especially on warmer speakers that can’t take advantage of the EPS’s qualities. Some may like the stand alone on some recordings, the full boat on others!

So, at present Blue Circle actually has three integrated amps in the line. Further, the 022i and 002i/ESP now strike me (at least) as equals, two amps that will choose among us. The passionate, bass-loving, and connoisseurs of prime rib on one side, the discriminating lovers of eloquence, beauty, and nuance on the other. I’m not talking extremes here, just clear variations on the Blue Circle sound. The 022i is no dumb head-banger and the 002i/EPS is far from being a priss. These are Blue Circle amps, folks. As we have come to know, the 1022 school of Blue Circle amps and N series cater to different tastes. And Gilbert has the uncanny ability to ‘know’ and value both of these tastes — more important, to address them both brilliantly.

Price for the stand alone 002i is $5250. The EPS is an additional $1750 and can be added later.

Stereo Amplifiers

BC 1022  Benefitting from a technology trickle down (mainly its input stage) from the top of the “N” line, the NSL, the BC1022 is a 125 watt stereo amp which, used with an appropriate solid state amp (like the BC107), produces a somewhat purer and clearer sound that we’ve heard from Blue Circle up ’til now. It also puts out over four times the power of the NSL. Among the four new amps, the BC1022 is distinguished by a firm low-end grip and a subtle and beguiling bit of warmth that contributes to a remarkable sense of intimacy through the midrange. It sounds great on both the JMR Abscissas and Offrandes. Clearly the best value of the four, it sells for $4795.

NSP  The NSP is the result of Gilbert’s attempt to see how much better he could make the BC 1022 within the space allowed in his larger (BC 200 series) cabinets. Power is 90 watts rather than the 1022’s 125, but capacitance is way up from 488,000uF to 5,600,000uF! It too makes use of the NSL front end and can sound like a sibling of the 1022; but it has its own distinctly different sound.

Moving from the BC 1022 to the NSP, using a pair of JMR Abscissas, the larger amp found things on recordings that neither the 1022 nor my beloved FtTH2 could find and delivered them with magical grace, clarity, and speed. It was a startling experience, as if someone had suddenly thrown open the windows. In the upper mids and treble, the NSP can be gorgeous. Reproduction of timbre in the lower midrange and upper bass can be spellbinding. In combination they give a whole new meaning to the concept of transparency. The NSP has less of the bass grip and sense of weight than the 1022. It also lacks its subtly beguiling midrange. It has less personality, less character. But it has the magic that more clarity — especially timbral detail — more focus, discipline, control, speed, precision, and a quieter background can bring. The breadth of tonal values is extraordinary.

Some listeners accustomed to a simpler, warmer sound will be willing to trade off what strikes me as the NSP’s overall superiority for the less ambitious amp(s). I find listening to the FtTH2 and 1022 very pleasing on the Abscissas. But in the end, for me and my particular audio taste, it is no contest. On the matter of bass, the NSP won’t get more bass out of your speakers than they have. It is not a particularly meaty sounding machine, which the O22i and 1022 definitely are. But, as I found on Erik Traffaz’s Bending New Corners, where the acoustic bass nearly shook my 5000 cubic foot living room, it will get all of the honest bass that’s on a CD and that your speakers can reproduce. And the quality of the bass can be stunning. I would say it is true, honest bass.

Looking over my comparative listening notes on the NSP, the words that come up most often are “beautiful” and “interesting.” The NSP made some of my recordings sound more beautiful; it made all of them sound more interesting. I wanted to hear them again. I wanted to hear more CD’s. I was pleased, sometimes really turned on — and interested. Interested, fascinated, and intrigued.

But again, I can see how listeners could go either way on this. Some may not want to give up the 1022’s particular virtues for those of the NSP; others will laugh and say, “Are you nuts” Listen to the different textures of the different viols in Purcell’s Suite for Viols. Listen to how the NSP clarifies the bass. Listen to how real and present everything sounds. All true. $9,995.

NSL  In the world of amplifiers, this lower power solid state amp is unique, so far as I know, in generating its output from a great many op amps wired in parallel. The upside of this approach is an extraordinary gain in control, subtlety, and refinement — with no sacrifice in overall response from bottom to top. The downside, for those who consider it such, is that its output power is 28 watts into 8 ohms respectively. The NSL can be supplied with additional power on special order, but this requires many more op amps. From my listening experience and from the two reviews I’ve read, you should be sure you need extra power before even considering that option: it doesn’t sound anything like 28 watt amps is what I’m saying. I would be comfortable pairing it with any speaker of around 92 dB or more, maybe even something less sensitive in a smallish room.

My  direct experience of the NSL amplifier began in mid-November, 2015, with a demo NSL, a BC107 preamp, a Resolution Audio Cantata digital source, and JMR Offrande Supreme, V2’s, with Crimson cabling from stem to stern. It resumed in the summer of 2016 with the arrival of my own NSL — and the new NSC preamplifier designed specifically for it. The most important thing I can say up front is that with the NSC the NSL has brought me as close to my ideal as I expect to get in my lifetime — maybe another 10-15 years, 20 tops if all of the various celestial and medical meteors miss me. I can finally say, with full confidence, this is good enough. Actually, it’s so good enough, it’s ridiculous. That’s the first word I sent back to Gilbert after the first half-day of listening: “Gilbert, this is ridiculous.” If music is what matters to you most, the NSL may well be the best amplifier in the world.

I could compare the NSL with the NSP, which until recently has sat next to it on my Mapleshade rack, but at the moment that seems silly. Because the NSL has simply stepped clear and beyond it into another world. As good as the NSP is — and it’s very good indeed — and as audibly related to its sibling as it clearly is, comparing it with the NSL seems irrelevant. It’s the difference between a truly great effort and success. The NSL doesn’t sound like a better NSP, it sounds like instruments and voices in my living room. Playing beautifully.

I told Gilbert I wanted to hear his best before I was finished with this whole business and hobby. With him since the BC3 Despina and BC 2.1 of many years ago, I simply had to hear him at his best. It became a matter of wanting to hear the best audio designer I know at the top of his game, regardless of where he goes from here. No one understands how art and technology go together like Gilbert. No one. I heard that back at the beginning.

Hearing the NSL tells us where it’s all been going, if we hadn’t guessed: what it’s always been all about. What the original room heater Class A gear, all of those hybrids, and now the latest all solid state gear were searching for. Unlike life, a narrative gets its meaning from its ending. Even if this isn’t the ending.

The NSL gives us something close to Absolute Presence. We are not looking through a clear window. We are sitting in the concert or jazz hall in the presence of the musicians. We hear behind them, seemingly inside them, and we feel the frontal wave of their sound. We can hear everything they are doing and it all fits together and we are mesmerized by it all. Music from the NSL, especially when coupled with an NSC, inhabits the air. To my ears, it is the ideal we music loving audiophiles have always sought. One of the most delightful features of listening to this amp is hearing all of the instruments that make up an orchestral chorus. The emotional thrill that degree and kind of clarity effect can generate — bassoons, cellos, double basses, trombones, each with their individual voices, all singing together — is impossible to describe. The effect is almost visual.

What are the most significant attributes of the NSL?

SPATIAL DEPTH. A sense of space, of a performing venue.

EASE. That belies the NSL’s modest power. A smoothness and lack of effort that sometimes surprises and even amazes us. An ease that becomes…

BEAUTY. Ease may finally be what we mean  a great deal of what we mean by beauty in performed music.

DETAIL, NUANCE. The seemingly absolute retrieval of instrumental sound, timbre. Qualia.

CLEAR AND NATURAL BASS. Low brass are stunning clear and like beef steak. Some will object to the NSL’s bass because while it has extraordinary clarity, body and impact, it hasn’t the weight, the avoirdupois of 300 watter. Fat it ain’t. You can’t have it all. You have to choose. I choose NSL bass.

Marc Mikelson has always seemed to me to get Blue Circle better than most. Here’s what I think is the essence of what he says in his review of the NSL posted on the BC website:

Piano, horns, and strings were marked by an effortless ability to cascade into the soundstage, their attack and decay prolonged. There seemed to be more of the instruments’ elemental selves, and less of an electronic signature, than with so many amps, even exceptional ones…In this way, the NSL was a sonic peculiarity: a component that was both highly detailed and abundantly easeful, presenting the music with precision and naturalness…The harmonic refinement it packs into its 28 watts is truly unique in my experience, bringing music to life in a fresh way.


The NSL is far more expensive than any of the other BC amps. If I weren’t in love with the sound of musical instruments and voice, I would call it a luxury. It is a luxury. But for those of you for whom Blue Circle has become the standard, if it is affordable, look no farther. The NSL is The Amplifier.

I write in my introduction something to the effect that gear can’t make music better. When I listen to the NSL, as with no other amplifier to date, music does in fact sound better. Composers want us to hear the bassoons and the cellos and double basses separately and together. When I’m reviewing CD’s for Positive Feedback on several different audio systems, I actually like the music better on the NSL. What else is there to say?  $19,500.

NSW 300

A new, high powered N series solid state stereo amp due out any minute. Early listening reports say its voice is somewhere between that of the NSP and the NSL. Stay tuned. $10,000.


Digital to Analogue Converters

Blue Circle’s best dacs mate wonderfully well with any systems I can imagine and do their best to tell us that digital will be around for along time.

BC 509, 507, 505. An affordable series of dacs that are already receiving high praise from customers. Stay tuned. $1205, $2195, $4750.

BC 501ob with optional purple-heart walnut faceplate.

BC501ob, BC501ob LOC. The ob version, with its external power supply, can hold its own with dacs for as much as three times its price. Dynamic, spacious, clear, physically warm, and smooth, it presents music with natural presence and authority. Instruments have has their true character and full weight through this all-solid-state dac. Compared with Audio Note tubed dacs, the 501ob gives the impression of greater weight but less harmonic enrichment: it is clear from corner to corner; and it has more natural texture and backbone The Audio Note dacs prioritize beauty, sounding sweeter, a bit softer, harmonically richer. Which you prefer will be entirely a matter of personal audio preference. Both work extraordinarily well. Compared with the Resolution Audio Cantata one-box player, the BC dac is warmer and richer sounding and not quite as fast. The choice here will depend on taste, as so much of especially digital-to-analogue conversion does.

The LOC version expands on all of the standard 501ob’s virtues in the same ways all of Blue Circle’s various power supply and capacitor upgrades do in other Blue Circle components. Essentially more ease, dynamic headroom, and realism.

Match your Blue Circle dac with an Audio Note CDT 2 II, CDT 3, CDT 4, or even a CDT 5 transport and you’ve got a great digital front end. I have yet to hear the baby dac. Price for the 501ob is $8630, 501ob LOC for $11,500. All can fitted with USB inputs as an option.
Blue Circle Line Conditioners

Blue Circle’s Music Ring line conditioners have been around for a while now and do a very creditable job. I have used an MR800 in the past and was pleased with it. But I wanted more, so I brought in an Audience AdeptResponse and got a LOT more. I got more of everything I wanted but also an uninvited boost in testosterone. I liked that – it improved the performance of both my Blue Circle and Manley amps, so I didn’t complain. In its new, revised version it is even better and has less testosterone, good enough to merit an award from me on Positive Feedback for 2007. But.

BC 6000, BC 6020

But, in late fall of 2007, I heard the BC6000. And the AdeptResponse had to leave. The BC conditioner made both my Blue Circle and Manley amps sound better still, but this time in the areas of clarity, refinement, and beauty, which are important to me. On my Audio Note M6 preamp and Neiro monoblocks, I got more ambient information and a noticeable increase in musical energy. This is the best piece of line-conditioning equipment I’ve heard and given the price of the competition, it is a steal. It is so much better than the Music Rings that I’m not even going to talk about them any longer. Go directly to the BC6000, in either the six, twelve, or fourteen outlet versions, and don’t look back. Probably the most bang for the buck in the Blue Circle line. $1975, $2560, and $2680 respectively.

Of course you could also jump directly to the new BC6020! More filtering, more everything good. $2995.