August 2007

AV123 Strata Mini Loudspeakers

by John Crossett

Review Summary Sound "Musical to the extreme" with "low frequencies aplenty. Not just bass for its own sake either, but good, tight, articulate bass that went deeper than I thought possible in my room." "Rock was fabulous, and organ aficionados should plotz when they hear how well the deepest organ notes are reproduced by these speakers." However, they "offered a rear-hall view of the music" and "they never quite managed to present the dimensional images, especially of vocalists, that other speakers do." Features "Yes, that’s real rosewood veneer, along with a 1" planar-magnetic tweeter, an 8" planer-magnetic midrange, and a 5 1/2" midbass dynamic driver. There's also a 350-watt class-A/B internal amplifier that powers a 8" rear-firing subwoofer enclosed in that four-foot-tall cabinet." Use "Because of their integral subwoofers, connecting the Strata Minis to your audio system is more involved than you might think. Still, don’t be disheartened by all the input and output jacks and binding posts you see around back of each speaker. Sure, it all looks daunting, but the owner's manual goes into nauseating detail as to which should and shouldn’t be used, and why." Value "Based on my experience with the Strata Minis, AV123 is making 'unusual' and 'unique' speakers for audiophiles on a budget and putting a new spin on the Chinese influx into high-end audio."

Where have you gone, affordability? Where have you gone, value? Where have you gone, affordable, value-packed gear that sounds better than it should? For that matter, where have you gone, Audio Alchemy?

The answer to the first three of these questions is, for the most part, the Far East, China in particular. The answer to the final question is, in part, to Longmont, Colorado. Mark Schifter, co-founder of Audio Alchemy, has resurfaced with AV123, his new mail-order-only company. Audio Alchemy was famed in its day for bringing to market affordable digital gear that delivered far more in the way of sound quality than its chump-change prices would have deemed possible. Unfortunately, it closed its doors a number of years back. In the spirit of Audio Alchemy, AV123 offers a surprising number high-value, low-cost products of all stripes to audiophiles on a budget, including the Strata Mini loudspeaker.

Look closely at the Strata Mini and try to guess its cost. Looks expensive, doesn’t it? Yes, that’s real rosewood veneer, along with a 1" planar-magnetic tweeter, an 8" planer-magnetic midrange, and a 5 1/2" midbass dynamic driver. There's also a 350-watt class-A/B internal amplifier that powers a 8" rear-firing subwoofer enclosed in that four-foot-tall cabinet. Got a price in mind yet? Good, now cut it in half. AV123 offers a speaker packed with goodies for $1995 USD per pair (plus shipping, of course) and does so with a 30-day money back guarantee.

The Strata Mini is either a three-and-a-half-way (which is how AV123 describes it) or four-way speaker, depending on one's point of view. The speaker stands 47"H by 11 1/2"W by 17 1/2"D (at the base, the top is only about 4" deep), and weigh 95 pounds. On looks and feel, you certainly get a lot for your money with the Strata Mini.

Manufacturer-supplied specifications are impressive. Frequency range is 27Hz-35kHz, nominal impedance is 8 ohms, and sensitivity is rated at 86dB. The crossover point for the subwoofer is user definable from 30Hz to 150Hz. This hands off to the 5 1/2" midbass driver at 80Hz, which crosses to the planar midrange at 650Hz. The planar tweeter covers from 4100Hz to 35kHz. The speakers are sloped back to offer a bit of time alignment, and the curved front panel helps avoid diffraction issues. Both the tweeter and the midbass driver are recessed into the front panel. The tweeter sits in an almost-horn-loaded slot. Whether this has any effect on the speaker's sound is open to debate, I suppose, although it may be an aspect of the time-aligned design.

Around back are a large heat sink for the subwoofer amp, that plethora of input and output jacks and binding posts, as well as rotary dials for crossover, phase and subwoofer level. There’s also an IEC receptacle for the included power cords that get juice to the subwoofer amps.

One final thing you’ll note on the back is a sticker that proudly proclaims that the Strata Minis were built in China. Given the stunning good looks and top-notch build quality of these speakers, I think writing off Chinese audio goods as obviously inferior is careless. When you look at them on paper or see them yourself, the Strata Minis are a match for almost any speaker out there.

Toil

Because of their integral subwoofers, connecting the Strata Minis to your audio system is more involved than you might think. Still, don’t be disheartened by all the input and output jacks and binding posts you see around back of each speaker. Sure, it all looks daunting, but the owner's manual goes into nauseating detail as to which should and shouldn’t be used, and why.

To connect to the amplifier, you run a single set of speaker cables from your amp to the heavy-duty five-way binding posts. You then have to decide how you want to connect to the subwoofer. AV123 recommends using the supplied jumpers from the binding posts to which the amp connects, but you also can use a set of interconnects from your preamp to the inputs on the rear of each speaker. I tried both options and settled on the supplied jumpers. The sound was simply more seamless this way.

Positioning the Strata Minis was not simply a matter of plopping them down in any reasonable spot and connecting the electronics. Oh sure, that could be done, and you’d get decent sound for your trouble, but if you want to hear these speakers at their best -- and who wouldn’t? -- you’ll need to spend some time experimenting with placement. The owner's manual discusses the subject somewhat. It recommends using the rule of thirds as a base point, but also suggests experimentation, which is what I recommend.

In my 13'W x 15 1/2'L listening room, I found that 3' 6" from the side wall to speaker center and a bit over 4' from the front wall to the sloped front baffle, with my listening seat 9' away, worked best. The speakers were toed in so that I could just see the inside edges of the cabinets. I tried both the rule of thirds and the Cardas method before finally adopting a mixture of both filtered through my own experience, which was based on listening. But, as you can imagine, that took quite a bit of pushing and shoving. Here? No. Here? No. How about here? Yeah, that’s better. I finally stumbled on the position that allowed the Strata Minis to sing their best. Luckily, the speakers slide easily on carpet.

Once I had the positions figured out, I screwed in the adjustable brass spikes and began the laborious task of adjusting all of the subwoofer settings. Once again, the owner’s manual comes to the rescue with well-written instructions that can save you time and anguish. The crossover point between the 5 1/2" midbass driver and the subwoofer can vary from 30Hz to 150Hz. AV123 suggests using the midpoint to start, but I found that setting the dial at 1:00 -- about 95Hz -- offered the best integration in my room. Of course, your results will vary. I left the phase set at 180 degrees -- and, yes, I tried it the other way too, but I wasn’t as happy with the results. Finally I got around to setting the subs' output level. The manual goes into detail about how to do this -- provided you have a Radio Shack SPL (which is notorious for poor resolution in the bass region). I don’t have one, which may have been a blessing, so I adjusted by ear. AV123 suggests beginning with the dial at the 12:00 position. I did just that and then went slightly up and down until I reached the spot where I found the best integration of bass and midbass, which for me was about 10:30.

Time to listen

Once I had the subwoofers dialed in, the Strata Minis had low frequencies aplenty. Not just bass for its own sake either, but good, tight, articulate bass that went deeper than I thought possible in my room. I guess that’s one of benefits of having a 350-watt powered subwoofer built into each speaker. It’s also the major reason the sound of these speakers is on the dark side of neutral; no matter the subwoofer settings, the Strata Minis seem weighted toward the bass. Consequently, playing music that depended greatly on the low frequencies to drive it along was a joy to hear with these speakers. Rock was fabulous, and organ aficionados should plotz when they hear how well the deepest organ notes are reproduced by these speakers.

To give just one example, Chris Jones's "No Sanctuary Here" from the Stockfisch SACD sampler Closer to the Music [SFR 357 4003 2] starts off with a driving bass line that anchors the song throughout. With the Strata Minis, I not only heard the bass, but felt it as well. I not only heard the bass guitar, but I heard what the bassist was doing with his instrument to achieve that driving beat. I’ve rarely heard better low frequencies, even from speakers that are far more expensive.

All of this made the Strata Minis sound musical to the extreme. They neither homogenized the music into a sonic blob nor thrust a wall of detail in my face. The Stockfisch sampler showcases primarily singer-songwriter music, so it offers a lot of acoustic instrumentation -- guitar in particular. The Strata Minis didn’t disappoint. I could hear the fingers on the strings and the body resonance of the guitars, but the speakers never turned analytical. Other similarly priced speakers may get one or the other part right, but rarely both. The Strata Minis reproduced both in correct proportion to each other.

One area that gave me initial pause was the treble, because of that planar-magnetic tweeter. Would the highs be dull and rolled off or bright and overly detailed? Initially the treble of the Strata Minis was lacking in air and extension, but as the speaker broke in, the high frequencies loosened up more and more. Still, cymbal strikes never wafted off into eternity. One way I found to alleviate this to an extent was to make sure I followed AV123’s mandate to have my ears at tweeter level. This was a problem, as my listening chair placed me well below that magical level and caused the Strata Minis to sound a bit dull. A hard folding chair got my ears up where they belonged, and then the treble opened up and sounded more realistic.

The Strata Minis did not do the 3D aspect as well as the very best speakers I've heard, but they are the equal of many I've listened to in their price range. It's not that they presented cardboard cutouts of the musicians, but they never quite managed to present the dimensional images, especially of vocalists, that other speakers do. They also don’t portray a very deep soundstage, although width was excellent. Oh, you get a sense of the soundstage’s size, but what you don’t get are layers upon layers that stretch from the front plane of the speakers back. Classical music proved this point. I could hear all the sections of the orchestra, but not how far back each person was sitting or the back wall of the venue. I’ve only heard very good (and very expensive) speakers manage to convey this quality, so maybe I'm asking too much of the Strata Minis.

Related to soundstaging is perspective. The Strata Minis offered a rear-hall view of the music, as opposed to a midhall or floor-seat. I always had the feeling that I was looking down on the proceedings instead of up at them -- a bit disconcerting at first. The Strata Minis didn’t project singers or instrumentalists forward of the speaker plane, preferring instead to keep them either even with or behind the speakers.

Still, the Strata Minis worked very well in a two-channel audio/video system. Their musical nature and ample bass always reproduced music or movie soundtracks in a pleasing way. I can just imagine what four of these -- and the accompanying center-channel speaker -- would do for a full blown home-theater system. You could put together a nearly full-range speaker system for the cost of a stereo pair of domestically built speakers, and you wouldn't need a separate subwoofer.

Comparison

There are two major areas in which the AV123 Strata Minis have it over my reference Magnepan MG1.6es (currently $1775 per pair): appearance (looks, size and spousal acceptance) and bass response. That relatively small footprint combined with the beautiful rosewood veneer makes the Strata Mini a speaker you’ll be proud to show off and one that should garner a positive response from your domestic partner. In comparison, the Maggies, as slim as they are, look more like room dividers and are therefore a much harder sell to your significant other.

More important to audiophile types like me is the bass response of the Strata Minis, which was a huge improvement over that of the MG1.6es. The Maggies may go down to 40Hz, but no lower -- and with no real heft except that which your power amplifier can provide. The Strata Minis are said to reach 27Hz almost flat, and they sounded like they reached that with ease in my room. The Strata Minis could shake my floor and set my pant legs aflutter -- no wimpy bass here. They sounded deep, tight and articulate. The Maggies, on the other hand are semi-deep and semi-articulate down low, but they won’t rattle anything greater than a piece of rice paper.

An example of what I’m talking about? How about James Taylor's "Gaia" from his Hourglass SACD [Columbia CS 67912]. Played back though the Strata Minis, the tympani in the final verse had thunderous power. Played back on the Maggies, all I got was a hint of the power of the instrument. Both speakers did an excellent job of defining the whacks to the tympani, but only the Strata Minis conveyed the full sound realistically.

Where the Magnepan speakers top the Strata Minis are in the areas of atmosphere (the way they convey space), coherence, and treble sparkle. The '1.6es are all about space and coherence. They offered a better sense of the recording space, one that eludes many inexpensive box speakers. They accomplish this, though, at the cost of image specificity, which is a bit less sharply defined than that offered by the Strata Minis. The Maggies also present the sound as more of a continuous entity -- what I meant by "coherence." The Strata Minis, despite their planar midrange and tweeter, just couldn’t keep up with the full planar panels of the MG1.6es. As good as they are, the Strata Minis still sounded like a collection of drivers.

Regarding the treble of these two speakers, it’s not that the Strata Minis aren’t detailed in the high frequencies -- they are. It’s just that their highs don't extend out as far as those of the Magnepan speakers. When I played The Three Sounds' Moods LP [Blue Note ST-84044], Bill Dowdy’s cymbal strikes seemed to waft off into nothingness more thoroughly with the '1.6’s, even when I was sitting on axis and at ear level with the tweeters of the Strata Minis. I also heard more of the cymbal's tinginess, and could discern its size and where Dowdy struck it via the Maggies.

While I'm not talking about huge differences between these two sub-$2000 speakers, it's the sum of the small things that can cause you to choose one speaker over another. Personal preference also plays an important role. If you’re a Magnepan guy, you’ll hear the box and crossovers of the Strata Minis -- and the bulk of speakers on the market -- as faults. If you come to the Strata Minis from a standard dynamic speaker, you might find that their mixture of drivers and powerful low frequencies offer the sound you're after.

Conclusion

There was a long time when I thought the Magnepan MG 1.6es had no competition in their price bracket. They are sonically sophisticated, and they just plain look cool -- more like attractive dressing screens or room dividers than loudspeakers. "Unusual" and "unique" describe them well.

Mating planar and dynamic drivers to a powered subwoofer, the Strata Minis aren't really like any other speakers on the market. They offer some distinct sonic virtues, including powerful bass and a music-friendly demeanor, and only a few areas in which they show obligatory cost-cutting measures. Being made in China, however, means that there are fewer of these compromises than you’ll find in a domestic speaker of the same price. Toss in their fabulous looks and you might find yourself the proud new owner -- with domestic harmony as an added bonus.

It looks as though Mark Schifter has forgotten none of what he learned at Audio Alchemy. Based on my experience with the Strata Minis, AV123 is making "unusual" and "unique" speakers for audiophiles on a budget and putting a new spin on the Chinese influx into high-end audio.

...John Crossett
johnc@soundstage.com

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