May 2010

Blue Circle Audio BM2 Loudspeakers

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Had I played life safe, I probably wouldn’t have quit my job in high tech in the 1990s to start up an online magazine. But if I hadn’t, I wouldn’t have had as much fun doing what I really like to do, and the SoundStage! Network wouldn’t exist today.

I suspect it’s been pretty much the same for electronics designer Gilbert Yeung. He could probably have found a job in electronics working for someone else, but instead he started up Blue Circle Audio, of which he is president, to produce some of the most original designs in all of high-end audio. His first products, from the mid-’90s, are legendary for their use of wooden knobs, stainless-steel chassis, and innovative circuit designs. I bought his BC3 preamp and BC2 monoblock amplifiers; I still use the BC3, and Yeung himself bought back my BC2s for his "museum." Yeung’s current Thingee products are turning heads and opening ears with their outrageous construction ("chassis" made from lengths of ABS pipe!) and very good sound. Every one of our reviewers who has tried these recent products has challenged their looks and praised their sound. Yeung took a risk in starting his company, and continues to take risks with almost every new product he makes.

And he’s still challenging himself. Blue Circle Audio boasts a wide range of electronics that includes cables and accessories, and now Yeung has set the company’s sights on loudspeakers -- mainly so that, according to Yeung, "when they display at a show, they can show a complete Blue Circle system." Of course, he wants to offer them to consumers, too.

Enter the BM2 loudspeaker, which costs $4900 USD per pair in its standard finish of natural or black oak (the price rises to $6500/pair for custom real-wood finishes; contact Blue Circle for details). And, like everything else Gilbert Yeung has designed, the BM2 is novel.


Although Gilbert Yeung has expertise in entrepreneurship, risk-taking, and electronics, loudspeakers are not his strength. Therefore, to design the BM2, he enlisted the help of Ohm Acoustics, of Brooklyn, New York, which has produced speakers since 1971. The BM2 includes some of Ohm’s tried-and-true technology, notably their implementation of the Walsh driver, but also includes its own unique features. The BM2 is not a rebadged Ohm model.

The BM2 is a floorstanding speaker of modest size (38.5"H x 8.5"W x 16.5"D with grilles on) and weighs 65 pounds. Blue Circle claims bass extension down to 28Hz, a sensitivity of 86dB/W/m, and an impedance of 8 ohms. There is a single set of binding posts on the back. But to really understand the speaker, you have to understand at least a little bit about its Walsh driver, which forms the heart of the BM2 and of all Ohm Acoustics speakers.

Developed by Lincoln Walsh, who died in 1971, the Walsh driver resembles the usual cone driver, but is longer and works differently. Instead of the entire cone simply moving back and forth, as in a traditional dynamic driver, the Walsh cone is stretched and compressed, which essentially creates waves in the cone material itself. It’s this controlled movement that results in the excitation of the air that arrives at the listener’s ears. In the BM2 the Walsh cone is mounted on the top of the cabinet, above an aperture -- any sound emitted by the cone’s interior is directed into a small chamber inside the cabinet and absorbed there. Soundwaves emitted by the cone’s exterior are radiated equally to all sides of the speaker, making the BM2 an omnidirectional design.

The Walsh is wide-range but not full-range. The topmost frequencies are aided by a 1" soft-dome tweeter mounted on the tip of the Walsh driver and firing only to the front. Driver and tweeter are enclosed in a black "canister" of metal mesh that can’t be removed by the owner (the Walsh driver and the tweeter remain hidden from view). A switch on the rear of the canister lets you adjust the tweeter output level (see below). The unsightly canister is concealed by a rectangular grille covered in cloth.

Two 6" woofers are mounted on the front of the main enclosure to reinforce the bass. Because the Walsh driver extends quite low into the bass, it isn’t crossed over to the woofers at a specific frequency; instead, all three drivers work in the bass range, to provide the most surface area, and the Walsh is allowed to roll off naturally at the low end. This makes the BM2 a more or less two-and-a-half-way design.


I gave the BM2s lots of room to breathe in my room, which I do for all speakers that spray sound to the front, sides, and rear. I placed them about 5’ from the front wall and about 7’ apart, which left about 4’ to each sidewall. My primary system comprised an NAD C 565BEE CD player and an Anthem Statement D2 v.2 preamplifier-processor feeding a pair of Stello M200 monoblock amplifiers (140W into 8 ohms). I did all of my listening in the Anthem’s Analog Direct mode, which bypasses all processing. The speaker cables were DH Labs Silver Sonic Q-10 Signature, the interconnects Nirvana S-L.


I’ve long fancied omnidirectional designs for their spacious, boxless sound, but I’d never reviewed a speaker based on a Walsh driver, whether from Blue Circle, Ohm Acoustics, or anyone else. I had no idea what to expect from the BM2s. Would they sound similar to other speakers I’ve heard, or would they generate a sound uniquely their own?

I first concentrated on the midrange; in particular, how the BM2 reproduced voices. In my opinion, if a speaker doesn’t get the midband right and thus makes voices sound nonhuman, it doesn’t matter what else it might do well, because that’s what matters most. Voices must sound real.

I was pleased to hear a midrange that sounded well balanced and natural -- not too thin, certainly not too rich, and with a "rightness" that made voices sound real. Mariza’s all-acoustic Transparente (CD, Times Square TSQ-CD-9047) is a good test for female voice -- it’s naturally recorded, with seemingly little extra processing added. I’ve heard Mariza sing live, even unamplified, and on this recording that’s what she and her band sound like. I liked the way the BM2 made her voice sound open, effortless, and airy, yet never wispy or too lean. The BM2 was surprisingly transparent and quick, not at all unlike an electrostatic speaker. Think detail, speed, and incisiveness through the midband, along with a proper amount of the heft that more traditional, dynamic speakers provide. Is this a Walsh trademark? No idea.

What impressed me more was how the BM2 handled male voices, particularly those that can be reproduced with too much presence and weight. Johnny Cash’s voice on The Man Comes Around (CD, American 044007708309) was miked ultraclose and can sound too rich and resonant through speakers that overemphasize the lower part of the midrange. The BM2 didn’t. It conveyed just enough weight to sound immediate and clean, but never weighty, chesty, or bogged down. Likewise, midrange-centered instruments sounded splendid for their incisiveness and attack. Bruce Cockburn’s 1980 album, Humans, is considered by many (including me) to be his masterpiece, and the best you’ll hear it sound is on Humans: Deluxe Edition (CD, True North TN0317). Hugh Marsh’s violin plays a tremendous role on this album; through the BM2s it sounded extremely natural, as well as wickedly fast and clean. The BM2s had a transparency and immediacy that let me focus more on the music and less on my system.

I also liked the way the BM2s reproduced Willie Nelson’s Stardust (CD, Columbia/Legacy CK 65946), a classic from 1978 that many feel is one of his best. This, like the Johnny Cash recording, can sound amazing through a great system, but sounds flawed if some frequencies are overemphasized, making Nelson’s voice sound too nasal and coarse. The BM2s did a shockingly good job of creating a vivid, highly detailed sound in which Nelson’s voice was projected three-dimensionally in space, but without ever pushing the envelope too far and thus sounding nasal, coarse, sharp, edgy, or etched. I say "shockingly" because, in this respect, I’d put its sound in the company of the PSB Synchrony One ($4500/pair), Revel Ultima Salon2 ($22,000/pair), and JansZen Model One ($32,500/pair, now discontinued). The BM2 isn’t nearly as neutral as any of those designs (especially the ruthless PSB and Revel), but all four share similar qualities of speed and transparency.

The BM2’s bass and highs sounded a bit more conventional -- probably because, the atypical Walsh driver aside, the BM2’s woofers and tweeter are used in pretty typical fashion. Still, that’s nothing to balk at; its performance in these areas was good, even if Blue Circle’s claim of 28Hz bass extension seems optimistic. Realistically, the speakers could lay a firm foundation in my room down to the middle of the 30-40Hz range -- still quite ballsy, given the speaker’s size, and the ideal amount of low-end grunt for a medium-size room without completely overloading it.

The BM2 sounded weighty enough that no music lover should even consider adding a subwoofer, and they had what audiophiles like to call "sock" and "punch" -- in other words, impact, the opposite of slow, plodding, waterlogged bass. The drums on "Grim Travellers," from Cockburn’s Humans, didn’t have the subwoofer-like weight from the BM2s that they do through the reference-grade, triple-woofered, flat-to-20Hz Revel Ultima Salon2s, but there was still an impressive level of depth and punch that made the Blue Circles sound extremely satisfying. I also played some hard-driving, drum-heavy rock through the BM2s at volume levels higher than I suspect most would play them in their homes, and they held together without breaking up. This surprised me -- I’ve heard speakers of similar size, when placed under such stress, start to crackle and distort, and their woofers bottom out. The BM2s proved that they had guts.

The highs were clean and extended -- what you’d expect from a good, modern dome design -- but were most interesting when I used the switch on the back of the canister. My ears told me that it made 2-3dB of difference in the uppermost treble, which is not insignificant. Most of the time I used the BM2 with the switch down; for the most part, this sounded the most natural, and the speaker never hinted at being bright. But when I wanted a little more air and upper-frequency detail, I’d flip the switch up, which would raise the level of the top end and give the speaker a livelier, more immediate sound. Provided the recording itself wasn’t inherently bright, the "up" position was fine. But with poorly recorded material -- very hotly mixed pop records, and recordings that were thin and strident to begin with -- the BM2s would sound bright with the switch up, so I’d flip it back down to make the sound more palatable. After weeks of listening, I concluded that the buyer should be prepared to use the speaker with the switch in either position, depending on the recording played.

Of the things I’ve talked about so far, the BM2’s main strength was how it presented the midrange: it was immediate, revealing, natural, and transparent, the kind of qualities one gets from an electrostatic design. But another great strength of this speaker was something I haven’t yet mentioned -- the way the BM2s projected sound with such an uncanny sense of space and "freedom" that I couldn’t pinpoint the locations of the speakers except by sight. The BM2 shares this strength with other omnidirectional designs, such as Mirage’s OMD-28, which I considered one of the greatest values in high-end audio ($8000/pair, now discontinued). Nowadays, you’d be hard-pressed to find a pair, but if you do, buy them. The sonic illusion created by a pair of properly set-up OMD-28s or BM2s is awe-inspiring.

When fellow reviewer Jarrett Dixon came by to listen to the BM2s, he admired their natural and well-balanced sound, as I did, and he liked the immediacy of the midrange. But those weren’t what bowled him over. Rather, it was the width and depth of the soundstage. The sound traveled past the outer limits of the left and right speakers, but with no degradation of centerfill -- voices mixed to appear at the center of the soundstage hovered there in space, rock solid. Depending on the recording, the depth of the soundstage could extend far past the room’s front wall, to create a sonic illusion that wasn’t only speakerless, but wall-less as well. Images within the stage were still strongly placed -- better, in fact, than with the Mirage OMD-28s. I believe that’s attributable to the BM2’s front-firing tweeter, which gave stronger, high-frequency directional cues. This aspect of the speaker’s performance wowed Jarrett, and it wowed me, too.


Had Blue Circle Audio come out with a front-firing loudspeaker based solely on conventional dynamic-driver technology, even with high parts quality and generally good sound, they’d probably have had a hard time making inroads into the cutthroat speaker market. There are a lot of very good speakers out there selling for the BM2’s price, or less. Ask anyone who’s tried to start a speaker company in the last few years -- it’s next to impossible to firmly establish a new brand, and bringing out just another generic speaker usually results in a quick trip to obscurity.

So I think Gilbert Yeung was wise to recruit the folks at Ohm Acoustics to create something more distinctive. The BM2 is a compact floorstander with strong, impactful bass to about 35Hz, highs that are clean and extended and can be adjusted to suit the music and the listener’s taste, and an overall tonal balance that sounds natural, even if it’s not quite the epitome of neutrality. The BM2’s defining characteristics are two: First, its midrange is superb in its immediacy and transparency, and in its ability to reveal scads of detail without making any of it sound "etched." Female voices sound great, as do instruments of the same range, and male voices can sound incredible -- detailed, with just the right amount of heft. Second, the BM2’s way of portraying space and getting sound "out of the box," while keeping a firm grip on image focus, is uncanny. Time and again I was awestruck by the fact that these two speakers could throw out a holographic soundstage with a convincing illusion of 3D -- as good as or better in this regard than any other pair of speakers I’ve heard. These qualities make the BM2 special.

Playing it safe has its place, but not if you want to make a mark. Kudos to Gilbert Yeung and Blue Circle Audio for trying something unique and producing the BM2. It’s an intriguing design well worth listening to for the distinctive things it can do. At least give them a listen -- I thoroughly enjoyed my time with them.

. . . Doug Schneider

Blue Circle Audio BM2 Loudspeakers
Price: $4900-$6500 USD per pair, depending on finish.
Warranty: Five years parts and labor.

Blue Circle Audio, Inc.
Innerkip, Ontario N0J 1M0
Phone: (519) 469-3215
Fax: (519) 469-3782