Axiom Audio M3v3 Bookshelf Speaker
Reviewer's Note: Before this review was published, Axiom Audio contacted me to say that they'd measured the review sample after I returned it and found it to be defective. According to the company: 1) a running change was made at the time I requested the review samples, 2) the original review samples had hand-built crossovers that reflected the running change, 3) the hand-built crossovers were incorrectly assembled, which affected the performance of the speaker. I agreed to test a second sample, with the caveat that this time, Axiom measure the speaker to confirm the performance before sending it. I've kept the original review intact and added a new section below, subheaded "M3v3 Redux," to report on the results with the new sample.
A longtime fave of home theater enthusiasts, Axiom sells its speakers direct through its Web site. The M3v3 ($378/pr) features a 1-inch titanium-dome tweeter and a 6.5-inch aluminum-cone woofer, crossed over at 2.2 kHz and mounted in a rear-ported cabinet. At 13.5 inches high, it's one of the largest speakers in this roundup.
With a relatively large cabinet and one of the two largest woofers in this batch of minis, the M3v3 ought to have plenty of bass. And it does. It sounds fuller and more room-filling than any other speaker but the Hsu Research HB-1 MK2, although some of the smaller speakers, such as the Music Hall Marimba, came fairly close. It also plays loud, easily reaching party level when I slid the volume control up on my laptop computer connected to the Firestone DAC for Jeff Beck's crazily dynamic, almost comically muscular recording of "Rollin' and Tumblin'." Given that the amplifiers used for this test are conservatively rated at 200 watts per channel, that's pretty impressive power handling.
What surprised us, though, is the treble, which in the face of the woofer's prodigious output seemed rather dialed-down. While this didn't hinder the M3v3's ability to deliver a solid center image, it robbed the speaker of some of its stereo soundstage. "It seems like you're looking into the performance space, rather than actually being in the performance space," Greg said. I often found myself speculating about how much I'd raise the tweeter level to get a more natural balance. (I settled on 2 dB, but my measurement gear will tell me for sure.)
Every product has a buyer, so who's the buyer for the M3v3? Someone who wants a minispeaker with ample, powerful bass output and who grooves on very mellow sound.
Frequency response of the M3v3 measures 78 Hz to 20 kHz ±6.9 dB on-axis, ±5.9 dB avg 0°-30°. Measured impedance is 5.7 ohms minimum, 9 ohms average. Sensitivity from 300 Hz to 10 kHz averages 82.3 dB.
While I don't normally record serial numbers of review samples, I noted that one of the new samples bears the same serial number as the one shown in the back panel photo above, so I assume this is the same pair, presumably outfitted with new crossovers.
Obviously, since the new samples are a (presumably) modified version of the originals, I couldn't compare the original samples to the new. But I had a good substiute: the pair of Hsu Research HB-1 MK2 speakers also reviewed in this roundup. Our listeners ranked the HB-1 MK2 in the middle of the pack, and the M3v3 toward the bottom of the pack. Thus, if the second sample of the M3v3 was substantially improved, it should equal or even beat the HB-1 MK2. To compare the two, I used the same testing setup as before. As luck would have it, I realized when I went to match the levels that I couldn't remember which inputs on the switching box I used for which speaker, so the test was blind.
To the best of my recollection, the second samples of the M3v3 had the same sonic character as the originals. The treble was a dB or 2 or 3 too soft for my taste, and the sound had something of a closed (i.e., not open or spacious) character. It sounded like too much of the upper midrange and lower treble was coming from the 6.5-inch woofers, which will tend to "beam" at these higher frequencies. The HB-1 MK2, on the other hand, had a much more open and enveloping sound.
The second chart accompanying this review compares the frequency response measurements of the new sample of the M3v3 and the measurements I took of the original sample. As you can see, the differences are not large. I thought for a moment that maybe Axiom had mistakenly sent the same speakers back to me, and that slight differences in my measurement setup might explain the change, but the difference in the curves does appear larger than the usual session-to-session variation I've seen in my measurements, so apparently some change was made to the new samples. But it wasn't much of a change.
We'll have to stick with our original conclusion on this one.