May 2001Mirage OM-7 Loudspeakers
by Doug Schneider
I remember my first listen to Mirages M-1 loudspeaker when it was released in 1987. The speaker was awe-inspiring. It had a large, imposing appearance, and a pair sat in a room like monoliths straight out of Stanley Kubriks 2001: A Space Odyssey. And the sound? With ample power, the M-1 could fill a very large room and cast an enormous soundstage. That speaker cost $5000 USD per pair at the time, and it was the birth of what Mirage called the bipolar loudspeaker. Hot on the heels of the M-1 were a number of other models, including the smaller M-3 that I thought was the real killer of the bunch based on price and performance.
Enter the Omnipolar speaker
Mirage, a division of Audio Products International, has long abandoned bipolar terminology in favor of what they now call Omnipolar, presumably because they feel it better conveys the impression that a loudspeaker should radiate in 360 degrees.
And thats the key about the Mirage line. Almost all the Mirage speakers radiate sound forward and rear -- in phase! They do this via drivers mounted on the front and back of the speakers cabinet. Furthermore, the sound isnt coming straight as an arrow out of the front and back. Mirage designs the speakers so the dispersion characteristics of the drivers are such that the sound emitted to the side is controlled too. So you get wide and even dispersion from the front, back, sides -- even up and down. Essentially, then, the speaker becomes a 360-degree radiating column that energizes the entire room. Because of the nature of this type of speaker design, it is difficult and time-consuming to measure properly. In order to do so, you must measure whats called sound power -- the total energy emitted in a 360-degree arc around the speaker horizontally and vertically.
Whether were talking bipolar or Omnipolar, the goal with current-day Mirage speakers is the same as what the company was chasing when the M-1 was released. Ian Paisley, the head designer at Mirage, is a firm believer in wide-dispersion loudspeakers. He came to this conclusion by trial and error and from legendary work done at Canada's National Research Council. He and many other designers learned that the sound a person hears at the listening seat is a combination of the direct sound from the speaker and the reflected sound in the room. The best way to achieve great sound, Paisley feels, is to design a speaker that works with the room.
Is the Mirage way the right way to design a loudspeaker? From talking to many designers over time (who seemingly all chase subtly or drastically different goals), Ive determined that there is likely no perfect way to design a speaker. Instead, a great speaker is designed with the best balance of tradeoffs -- and that goes for expensive speakers too. As a result, I found it interesting to read in the Mirage literature that the company believes their speakers "sound more real than forward-radiating (unipolar) designs." Mirage is part of a very large company, Audio Products International, that includes Energy, Sound Dynamics, and Athena Technologies -- all makers of forward-firing speakers. I wonder what the designers in those groups have to say.
Although Ian Paisley is still the head designer at Mirage, Andrew Welker also carries the Omnipolar torch. Welker was instrumental in the design of all the new Omnipolar speakers, including the OM-7 and the larger OM-5 (with powered subwoofer section), also the smaller OM-9. As well, a new statement-level model has just been added to the line -- the $25,000-per-pair OM-1.
The floorstanding OM-7 under review here retails for $2000 per pair and comes with a five-year warranty. It features Mirage-designed and -manufactured drivers: two 1" Pure Titanium Hybrid tweeters (front and back), two 4.5" polypropylene cone midrange drivers (front and back), and one 8" polypropylene cone woofer (front only). Crossover frequencies are said to be 200Hz and 2kHz. The company rates the OM-7 as having 90dB in-room efficiency (shave off a few dB for anechoic efficiency) and an 8-ohm nominal impedance. Its not necessarily a difficult speaker to drive, but I found it best to use a good solid-state amp of reasonable power. Low-powered tubes likely wont mate well.
Bass response is rated down to 30Hz, which is realistic given the type of "whomp" I heard in my room. Essentially, this is a nearly full-range speaker (full range would be one that goes below 20Hz) that I would not consider using with a subwoofer. It's so well balanced, and I wouldnt want to risk messing that balance up.
The little tidbits that finish off a high-quality speaker are here in abundance. There are big, thick binding posts (two sets per speaker for biwiring, should you wish), spikes for penetrating carpet to keep the speaker rock-solid on the floor, and rounded, gold-colored feet that finish off the bottom of the speaker nicely.
I've always admired the look of the original M-series speakers -- big, bold, and more than impressive sitting in any room. However, I found the appearance of the previous generation of OM-series speakers to be a bit awkward. It was obvious that the company was trying to cut down the size of the cabinet and perhaps make it a bit more curvaceous -- after all, not everyone wants a pair of monoliths in their room. However, in doing so, Mirage managed to give the speaker something akin to a big rear end. The speaker just looked unbalanced.
However, thats all changed because all these new OM speakers are real head-turners. The OM-7 measures 43" x 11 9/16" x 14 3/8" and weighs 78 pounds. It's a gorgeous speaker. Frankly, when I got the pair in the room, I misunderstood their price and thought they were $3500 (the price of the OM-5). Given the fine appearance, I simply accepted the price. In fact, based on appearance alone, if someone told me the OM-7s were $5000 or $6000, I would have accepted that too. People wont think "ugly speaker" of the OM-7. Instead, theyre more likely to gasp and say "Whats that!?"
The speaker comes finished in high-gloss black or real cherry wood veneer. The way Mirage gets away with putting such a nice finish on these relatively inexpensive speakers is to use not too much of it. Similar to what MartinLogan does, the gloss black or cherry is applied more or less as trim, and the rest of the speaker is a plain black. The result is a nice contrast. I like both finishes, and it will likely be individual tastes that determine which one is more pleasing in your own room. The grilles are removable, but they're an integral part of the speaker, so you need to leave them on.
On the one side of the coin, I used the OM-7s with some pretty pricey gear, including Blue Circle Audios BC8 monoblocks being driven directly by the outputs of the Audio Aero Capitole 24/192 CD player -- this combination sounds fantastic! I then removed the Capitole 24/192 and used Simaudios Eclipse CD player and ran it through the Blue Circle Audio BC3000 preamplifier with outstanding results too. Speaker wire in both cases was Magnan Signature, and interconnects were Nordost Quattro-Fil. I then turned the tables a bit and used the much more affordable Roksan Kandy KA-1 integrated amplifier and KC-1 CD player. Speaker wire again was Magnan Signature, but for interconnects I used Nirvana S-L.
Ive heard all kinds of crazy notions about how a speaker that radiates like the OM-7 will sound. This speculation most often results from someone looking at the speaker, seeing the front- and rear-firing drivers and then making a wild guess on how that will sound. No, Im sorry to say that these Mirage speakers dont do any sort of magical tricks, but the fact that they do produce sound with such wide dispersion means that they have some unique characteristics, and these are accentuated by in-room positioning.
In order to get the kind of sound that the OM-7s are capable of, you must not place them very close to the front wall. Doing so seems to cause all sorts of problems. They also need a room to be a reasonable size -- 10' by 12' second bedrooms should not be used. I normally pull speakers way out into the room anyway, and for the OM-7s, its mandatory -- I left at least five feet behind them. With that done, the speakers have room-filling capabilities, and they sound nearly the same wherever you walk in the room. This is no head-in-the-vice speaker. Sure, the sweet spot is still in the center, and thats where youre going to be getting the best soundstage re-creation, but for general listening and proper tonal balance, you can be just about anywhere. If you cant give this speaker the proper breathing room, you should consider the smaller OM-9.
It wasn't too surprising to discover that the sound of the OM-7s is reminiscent of that of the great M-1 (and M-3) -- but better in many ways. The OM-7s are big and robust, just like those original speakers. One downfall I remember with the original M-series speakers is that they were a little too robust and sometimes a little woolly, particularly in the bass. That isnt a problem here. The OM-7 is strong, tight and well defined. Its not as lean or visceral in the bass as, say, Paradigms $2000 Active/40 speakers. But it is solid and gives a firm foundation to the music. I never thought that U2s Achtung Baby [Island 510490] had much bass, but when I played it using the Simaudio Eclipse CD player in 24/96 mode along with the Blue Circle BC8s and BC3000, the sound was room-filling and jaw-dropping. I was completely impressed.
OK, so I went overboard and matched the OM-7 with some very expensive electronics, probably far more expensive than anyone would consider using. But this taught me a quick lesson: the OM-7 is suitable for such fine gear. And despite being more than twice the price of the speakers themselves, Simaudios Eclipse CD player proved an ideal match. One of the players strengths is its ability to deliver large-scale dynamics in a way that few CD players can approach. As well, it can "slice" out detail in a recording, again like few other CD players. As a result, when I played "One" from the same U2 album, it was as if I were hearing a new recording. The vocals, guitar and drum all had unbelievable impact and intensity. Furthermore, the delineation of the musicians is the best Id heard in my room from any speaker. The OM-7s midrange has excellent purity, and the high frequencies soar without any "tizz" or hash. Given a top-notch front-end, the Mirage OM-7 is capable of something remarkable.
But this isnt to say you need to use the speakers with big-buck gear. The Roksan Kandy KA-1 and KC-1 together cost less than the speakers do ($895 a piece), and they're a much more rational and cost-effective way to go. Sure, they dont get you to where the cost-no-object stuff resides sonically, but what you sacrifice is in no way comparable to what you save in money. So just as the OM-7s can be mated with really expensive electronics, they can be matched with reasonably priced gear too.
Either way you go, what the OM-7s do exceptionally well is give a large, room-filling sonic experience with excellent dynamics and overall weight -- they sound like the large speakers they are. Overall tonal balance is exceedingly good, and because of the OM-7s' dispersion characteristics, they sound largely the same wherever you walk in the room. Left-to-right imaging is stable and has good precision. Imaging is not as sharply focused as with some speakers Ive heard, such as the $2000 Revel Performa M20s, but what the OM-7s sacrifice there they give back in some other areas, which Ill expand on below. Depth of stage is also very good. Just like the lateral imaging, it may not be the very best, but its difficult to criticize.
While I played the OM-7s with my usual rash of demo material, I also find it valuable to use loudspeakers with current, more accessible material that many people will likely be hearing them with. Besides, some audiophile-approved speakers Ive heard have failed miserably when trying to play popular music. That said, I didnt expect the heavily EQd Destinys Child Survivor disc [Columbia CK 61063] to sound good at all. But, to my surprise, it sounded fantastic. As with many albums, its bass and treble are mixed way too high, presumably to make the disc sound good on equipment that doesnt have bass or treble (car radios, boomboxes, etc.). The ever-so-slightly-rich OM-7s did this recording plenty of justice. Bass was strong, tight and authoritative with excellent pace, rhythm and drive. The highs were a little too much for my tastes, but thats not the speakers fault -- it's on the recording. The nature of the tweeters sound is similar to that of the M20 -- clean, extended and precise. This is slightly different than the highs of Mirages own MRM-1 speaker (a $2200 front-firing two-way minimonitor), which has every bit as much extension but is a little softer and more resolving in its decay -- something I prefer. What surprised me most, though, was the midrange, which was pure, non-fatiguing, very clear and ultimately excellent at conveying the three singers voices on the Destiny's Child disc.
More neutral and natural-sounding CDs came across equally as well. Ive been using the soundtrack to All the Pretty Horses [Sony Classical SK 89465] of late because of its warm, rich musical balance and sense of grandeur and authority on some tracks. I simply love it on the OM-7s because of the strong, room-filling sound the speakers can achieve. The OM-7s have a way of enveloping you in a soundfield, and this is completely addictive.
On the downside, this speaker does have some limitations -- not surprising given that it is still a moderately priced speaker. First off, despite the excellent bass foundation, it is not truly a full-range loudspeaker that hits 20Hz. I say this not because I think it should be at this price range (I dont know of any speaker that is truly full range at this price -- or more accurately is full-range with high-quality bass too), but because I feel in many ways that the OM-7's overall performance is comparable to that of more expensive speakers.
Next, in terms of the midrange and high-frequency performance, the OM-7 has extremely good clarity and a warm-but-even tonal balance. But its not as open and airy as some speakers. It leans to the warmer side, and it is just a tad bit closed in up top. For example, Ani DiFrancos new Reveling: Reckoning CD [Righteous Babe Records RBR-024-D] has some stunning sound, in particular the simple tracks consisting of mainly voice and guitar. Played through the OM-7s, DiFranco's voice is warm and natural-sounding, but the upper midrange and lower high frequencies are just ever so slightly closed off (not to be confused with rolled off). In short, DiFranco does not soar as freely as with some speakers.
Finally, the only other strong criticism I can make is in regard to overall resolution. The detail is not as abundant as with some competitors -- and even with Mirage's own MRM-1. For example, with a hyper-revealing speaker, you can hear every last nuance on some of my test discs, but the OM-7s stop just short of that.
But you must remember that every speaker design is one that involves some degree of tradeoff and, after all, this is a $2000 speaker, not a $20,000 one! Revels excellent M20 does let you hear almost everything on a recording; however, it doesnt have the large-scale dynamics or near the bass depth of the OM-7. Likewise, Paradigms innovative Active/40s give approximately the same type of bass extension and can show a little more resolution and detail, but they dont have quite the bloom and warmth that the Mirage OM-7s do. Finally, although all the speakers I mentioned came about as a result of the NRC research and are wide-dispersion designs, the OM-7 is the champ at the "walk around the room test." Theyre fine-sounding from any location and truly present an enveloping soundfield. For $2000, you cant necessarily have everything, but you can have a fine floostanding loudspeaker.
With the latest rash of truly excellent speakers Ive gotten in for review at around the $2000 price point, I wonder why some speakers have to cost so much. Yes, I know that there are reasons; however, what a speaker like the OM-7 gives you is rare, especially for its price. For $2000, you get a nearly full-range, very wide-dispersion pair of speakers that in many ways can rival speakers costing much more. No, the OM-7 is not the pinnacle in terms of resolution, and there are some other tradeoffs, but overall its sound is so good that you can choose to mate it with some really great electronics, or some equally great but less expensive gear. My strongest recommendation is to use it in a big room with a good solid-state amplifier -- the OM-7s need some firm control in terms of power and some breathing room to sound their best.
Finally, it will be trivial for some but relevant for others: its worth stating again how impressive-looking this speaker is. Sure its big, but it commands your attention -- visually and sonically.
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