Mirage OM-6 loudspeaker Page 2
One caveat about the choice of amplifiers: Though it may be tempting to consider the use of a low-power amp to drive the mid/tweeter section of the loudspeaker, remember that this amplifier is always being driven full-range. It is thus still subject to clipping from strong low-frequency signals, even if these signals do not reach the OM-6's mid/tweeter–range drivers. The only way to avoid this is to roll off the upper-range amplifier's bass response. This may be done with anything from an outboard electronic crossover (only the high-pass section is required) to a high-quality capacitor of the appropriate size at the input of the amplifier.
The proper choice of crossover point and technique to use here is beyond the scope of this review. If you do perform some sort of high-pass filtering at the front of the mid/tweeter amplifier, then you must use the line-level connection to the subwoofer. (There will be no deep bass present at the loudspeaker taps.) With any amplifier of sufficient power, however—certainly anything above 100Wpc—audible clipping should not be a concern in normal use.
Largely because of its adjustable bass, setup of the Mirage OM-6 was far easier than with most normal loudspeakers. I obtained good results from two room configurations: firing across a room diagonal, or placed several feet out from and parallel with the short wall. Most of the comments in this review reflect this latter setup.
In both situations, the Mirages were placed well out from the wall behind them and toed-in toward the main listening position. Using a variety of program material, I set the bass level and equalization for best results. (The optimum settings will vary from room to room and position to position.) Male vocals proved particularly useful in making these adjustments. I used the furnished spikes; these included two attractive gold-plated feet that double as locking collars for the front spikes.
From the first audition, the OM-6's easy-on-the-ears, well-balanced, full-range sound made the right impression. According to Mirage, the samples we received had already seen some use and required virtually no break-in—I was able to jump immediately into "reviewer mode." But that wasn't easy; the OM-6es kept pushing me into "relax-and-enjoy." They were incredibly seductive, drawing me into the musical performance and refusing to distort the experience with their own distracting colorations.
No loudspeaker is entirely free of character, of course, and the OM-6 is no exception. But in the all-important midrange, the OM-6 is first-rate. The overall sound is a little laid-back and forgiving (more on that below), but my usual lineup of reference recordings emerged without a hint of nasality, unnatural edge or bite, or aggressive forwardness. Well-recorded vocals, the acid test for me, were completely natural, with an evenly weighted balance and believable vocal textures. The ability to adjust both the level and contour of the built-in subwoofers helped significantly to minimize any chestiness or boom on male vocals.
In fact, it was male vocals that I used to adjust the controls on the OM-6, falling back particularly on two old reliable references: Gordon Lightfoot's If You Could Read My Mind (Reprise 6292-2) and the Fairfield Four's Standing in the Safety Zone (Warner Bros. 26945-2). In my experience, when the balance is right, the former should have just a small degree of pleasing warmth, the latter just a little more (though not to excess). The surprisingly narrow range of the Mirage's controls at which these conditions were met is food for thought when you consider how seldom normal loudspeakers can be made to sound right through the midbass—not without careful, often tedious setup. And some loudspeakers refuse to fall into balance no matter what the user does—often for no other reason than a skewed top/bottom balance. I would certainly not claim that the Mirages can be made to sound optimum in every possible room, but their inherent flexibility greatly enhances their chances for success.
At the top, the OM-6 was open and detailed. There was a touch of fine grain present with both test amplifiers, though it was lessened with the Kinergetics. This suggests a slight rise in the Mirage's response in the sibilance region or slightly above. It may possibly be related, also, to its wide dispersion, which put more overall upper-octave energy into the room than typical direct-radiating loudspeakers. But I never found this quality irritating. The only downside was a small loss in the liquidity and sweetness of the upper treble. The upside was an open, detailed, but never etched or exaggerated sound—in other words, a convincing window on the recording itself.
The radiation pattern of the OM-6es enhanced this open quality—the sound was suspended in space around and between the loudspeakers. And unlike many loudspeakers that radiate in multiple directions, with the Mirages I never felt that I was listening to the ambience of my listening space rather than the ambience of the original recorded event. Still, this quality will certainly be dependent to a degree on your room and setup.
While the OM-6es were relatively easy to set up, I don't recommend positioning them so that their rear radiation fires into undamped room corners. Even if they're physically well out from the corners, this placement invites an unnaturally cavernous midrange coloration. (My listening room is not overly live, and the front wall behind the loudspeakers is damped from the outside of the loudspeakers into the corners.)
Soundstage placement with the OM-6es, while less pinpoint than you might get with, say, good minimonitors, was nonetheless natural. Depth was very convincing and, again, appeared to be that of the recording rather than a byproduct of the loudspeaker's radiation pattern. The dancer on Flamenco (Philips 422 069-2), for example, generated an astonishing sense of position, both in width and depth, as he worked his way around the "stage" in front of me.
Another engaging characteristic of the OM-6es' radiation pattern was the stability of the image as I moved laterally across the listening area. This does not mean that you'll get optimum imaging no matter where you sit—I know of no loudspeaker that will do this trick. Any loudspeaker capable of reasonably precise imaging will still work best from the sweet spot, and the OM-6 was no exception. But still, I got a believable image from any reasonable listening position. Furthermore, I heard no odd, abrupt shifts in balance and soundstaging as I moved across the room.
With many loudspeakers, such shifts are the inevitable result of the loudspeakers' limited horizontal radiation pattern, their response irregularities, and the room. It's not unusual for the sonic effect to resemble a sort of comb-filtering, with the images shifting radically, sometimes popping into focus, at other times sounding phasey and indistinct as you move farther away from the primary listening position.
With the OM-6es I was conscious of no such irregularities. With the loudspeakers toed-in toward the center I could, in fact, sit opposite the left loudspeaker and still hear a respectable soundstage spread evenly from left to right. This has useful implications for any application in which the loudspeakers must provide satisfying performance to a widely spread group of listeners—ie, home theater.
The OM-6's bass response was remarkable for a loudspeaker of this size. It definitely extended into the bottom octave, and while a few each of the best subwoofers and full-range loudspeakers offer more powerful sub-30Hz performance, you'll have to look hard to find them. On a wide variety of bass material—bowed and plucked double bass, bass drum, organ, piano, synthesizer, even video-type sound effects—the result was never less than convincing, and frequently thrilling. The famous falling drumset on Däfos (Reference Recordings RR-12CD, now available only on a reissue from Ryko) definitely sounded as if it was coming from a subwoofer rather than merely a good woofer. This is a subtle distinction; a good subwoofer energizes the room in a way most ordinary woofers can't quite manage. The percussion section on Vaughan Williams' Sinfonia Antartica (Koss Classics KC-2214) startled me upright. And Jean Guillou's organ transcription of Mussorgsky's Pictures at an Exhibition (Dorian DOR-90117) rocked the room.
Still, though the overall bass of the OM-6 was impressive, it wasn't quite awesome—there's still room for improvement in definition and power handling. While what I heard in the low end was often amazing, we're still talking here about 8" drivers pushed to their limits. The bottom octaves were a little full and rich rather than tight and highly detailed, and there was occasional audible overhang (possibly a result of bass amplifier clipping) when I worked the system hard. Push it just a little harder and the woofers began to rattle on extremely challenging material like the big bass drum on "O Vazio" from Tropic Affair (Reference Recordings RR-31CD), deep synthesizer bass such as that on "Psychopomp" from the Däfos CD, the subterranean growl in "Hell's Bells" from The Apocalypse Now Sessions (Rykodisc RCD 10109), and video sound effects such as the falling rock in the cave sequence from the Aladdin laserdisc.
But unlike most loudspeakers, you do have the option here of turning down the bass level without sacrificing overall system loudness: Apart from the bass limitations noted, the OM-6 played very loud without turning edgy or seriously congested. Turning down the woofer level slightly thinned out the overall balance, but also minimized bass overloading. But it's also fair to point out that this is unlikely to be a problem in a smaller space than my fairly large listening room, or at less demanding overall playback levels.
I've already mentioned the slightly laid-back, forgiving quality of the OM-6. This is a strength in that the Mirages were far less likely than most loudspeakers to sound irritating on less than the best program material, a weakness in that they sometimes just didn't "take off" dynamically when the music called for it. They seemed just a little lacking in "jump-factor"—the ability to startle with abrupt shifts in the microdynamics of the music. (This is opposed to their output capability, which, as I've noted above, was more than adequate.) I attribute this at least partially to their radiation pattern, though I also suspect a slightly recessed response either in the midrange or low treble—perhaps both.
But the OM-6 was both involving and detailed through the midband, which suggests that the recessed response (if it in fact exists) is not severe. In both bass power-handling and dynamic immediacy, the OM-6 was outdone by my long-term reference, the Energy Veritas v2.8, though the latter loudspeaker lacks the Mirage's adjustability and is therefore more difficult to position for optimum bass performance. But the comparison is hardly fair; the Energy sells for twice the price of the Mirage. There is, I suspect, a larger Omnipolar model in the Mirage pipeline which will give the big Energys a run for their (and your) money.
Minor quibbles aside, the overall performance of the Mirage OM-6 was hard to fault. I know of few loudspeakers that can match its extended frequency response, output capability, sheer listenability, and low coloration. Thanks to its separately adjustable subwoofer, it's relatively easy to position and not overly demanding of associated components. Its ability to maintain reasonable performance with less than the most pristine program material and in less than optimum listener locations strongly suggest that it just might be at home in an all-purpose, music/home theater system without the musical compromises that such a multi-use system sometimes involves. In fact, I definitely plan to try it out in just such a system for a possible future review in the Stereophile Guide to Home Theater.
In short, you don't need a crystal ball to figure out that I really like the Mirage OM-6. I suspect that you, too, just might be impressed.