Subwoofer Review - Stereo Integrity MAG 12

Ah, subwoofers. No sound system, home or car, is complete without them. Every shop you enter seems to sell subs, and as of late, it seems more and more shops are putting their own private labels on them. Different reasons motivate this trend. For some shops it adds to their bottom line, effectively cutting out the middle man and putting more cash in the till. For others it makes a statement of their expertise and depth of experience. Some get it right and some don't. Stereo Integrity in upstate New York took the plunge and created a couple of models, a 12" and a 15" they dubbed the MAG (as in magnificent?) 12 ($479) and, you guessed it, the MAG 15 ($599). For this issue I had the distinct pleasure of auditioning the MAG 12. Let's see what it can do.

Impression
Upon opening the woofer's box, I was greeted by a large, attractive, industrial-looking 12" driver packed securely in form-fitting foam. Included with this rather expensive subwoofer I saw an information sheet that lists the MAG 12's power handling as anything from 250 to 1,300 watts RMS. Also included are enclosure recommendations of 1 to 1.5ft3 sealed and 1.5 to 2ft3 ported for this particular sub. The motor structure contains some nicely chrome-plated components and the cast aluminum frame is covered with what appears to be a powder-coated metallic silver finish. To move air it uses a non-pressed black paper cone with "Stereo Integrity" emblazoned on the convex dust cap, surrounded by an obligatory (nowadays) wide, tall, foam surround and an integral rubber gasket/trim ring around the bolt pattern. Nothing too fancy, just kind of an understated elegance.

Build
The MAG 12 uses a 3" voice coil wound with aluminum wire on a black anodized former, dual 8" spiders, and thick tinsel leads that appear to be just the right length so they won't tap on the cone in a high-excursion situation. Also included are stout, nickel-plated push terminals for the dual 4-ohm voice coils. Supplying the force to move this assembly is a motor using dual 1" tall x 8" diameter ferrite magnets and a heavily beveled, chrome 1.5" tall backplate with a vented pole piece. Mounting depth on this big boy is 6", not including the 1.25" clearance needed to avoid obstructing the radiused pole vent, for a grand total of 7.25". This is not your space-saver woofer.

In addition to the appearance described previously, the frame used on the MAG 12 is the standard off-the-shelf 12-spoke basket we've seen several times before. Its design is nice and open, and its thin legs minimize ob-struction of air movement at the rear. However, this is an old design, and it's compact, so it doesn't lend itself well to super high excursion without consequences. Nonetheless, it works well in the MAG 12.

Manual
The "manual" included with this driver was a little skimpy. It consisted of the previously mentioned information sheet with enclosure recommendations and a description of the woofer's build. An additional sheet lists power handling on the MAG 12 as 900 watts RMS. So which is the correct figure, guys? Also included are Thiele-Small parameters for both the MAG 12 and MAG 15. There is a caveat included here that should be taken to heart by anyone using this woofer as an SPL piece: The MAG woofers are warranted for one year against manufacturer's defects, which does not include burned voice coils!

Installation
This woofer was tested in my '04 BMW 330Ci coupe. BMWs are built like tanks, so I folded the rear seats to approximate what it would sound like in a hatchback or small SUV. In other words, the output from the woofer would have an uninhibited path into the listening area. A bridged pair of channels of a Genesis Series III 4-channel amp was used to drive the woofer at approximately 300 watts RMS. (Genesis has a habit of seriously underrating the output of their amps, so it was probably more like 450 watts.) The driver was installed in a sealed, lightly Polyfill-stuffed MDF enclosure with a volume of 1.25ft3 after allowing for the displacement of the woofer. The box was aimed toward the rear of the vehicle in the right rear corner. The crossover frequency that seemed to give the best blend with the mids mounted in the front of the car turned out to be 70Hz with a slope of 24dB per octave.

Listening

Drum solo
Ron Tutt "Improvisation"
For my first listening test I decided to subject the Stereo Integrity MAG 12 to a drum solo by Ron Tutt. A lot of you out there have probably heard this selection before, as it's been included on quite a few demo discs. I've used this piece as a test for accurate drum tones and impact for many years. It's miked very close and is very well recorded. Tutt uses a moderately sized bass drum, so the driver in question should make it sound tight and appropriately sized.

My first impression of this driver is that it didn't call attention to its location in the rear of the vehicle. Its output coupled almost seamlessly with the front stage in the car. The bass drum didn't sound too large, and the impact was visceral and realistic. When Tutt started working his way around the drum kit, the floor toms had a nice pop to them and the bass drum roll practically shook the whole car. The woofer sounded pretty "fast" and accurate in this application, without overhang or distortion.
Score: 8/10

Rock
Dave Weckl "Heads Up"
Dave Weckl is one of my favorite rockers. You can always depend on him for a dynamic performance and a great recording. This selection features a slammin' bass and drum duo, and should give the MAG 12 a good workout. The MAG seemed to be in its element on this track: It appeared to have an affinity for smaller groups and less complex music. The definition of the bass guitar was very good if not exemplary, with no overhang, but good attack and decay. The impact and dynamics were also very good. The rhythm section was also featured and I must say the MAG 12 showed itself very well indeed - especially during the ensemble interplay between the bass and drums toward the end of the track. As long as things didn't get too complicated, the MAG 12 hung in there with the best of them.
Score: 7/10

Female Vocals/Jazz
Holly Cole "Je Ne T'aime Pas"
As any of you who have read my previous reviews can attest, I have a soft spot in my heart for Holly Cole and Co. The trio behind her consists of piano, acoustic upright bass and drums, all of which depend on a good subwoofer system to impart a sense of realism to the recording. As with the drum solo track, the bass appeared to come from the front stage quite convincingly, and the big fiddle sounded just like it should: big without being boomy. The lower notes of the piano had a nice weight to them also, and the drums blended well with the rest of the trio. Descending and ascending bass lines sounded very linear as they transition between midbass and subwoofer frequencies without any "hot" spots; and the bowed bass toward the end of the song sounded especially good. Nowhere did I hear any overhang or boominess, which is quite a feat when trying to reproduce the sound of a stand-up bass violin. Everything was nice, tight and controlled, and I easily differentiated the low-frequency sounds of the separate instruments.
Score: 8/10

Classical
Giuseppe Verdi "La Donna E Mobile"
This track is a recording of a full symphony orchestra in a large hall, so obviously it should sound big and powerful. Symphonies usually use large, 40" bass drums and tympani. This bass drum sounds every bit of 40", if not larger, and was realistically rendered by the MAG 12. The lower voiced instruments also had an appropriate weight to them. Maybe it's the recording, but the bass instruments all seem to become one when the entire orchestra comes in and things start to get really complex. It's difficult to pick out the individual sections. This woofer seemed, at this point, to be better suited to less complex music than a full symphony orchestra. In its defense though, it had very good impact and dynamics.
Score: 6/10

R&B/Blues
Susan Tedeschi "Little By Little"
Susan Tedeschi is the quintessential female "blue-eyed soul" singer and on this cut she proves it once again. This track features a predominant bass line that walks through the entire song. The MAG 12 made it sound like the bass player was in the car with me, with a full, dynamic, driving sound just like in a live performance, with good linearity as he ascends and descends the scale. At times the bass tended to overpower some of the other sounds, but I've also noticed this phenomenon on other systems when I've played this selection. All in all, I'd say the MAG 12 does a pretty good job on this one too.
Score: 7/10

Conclusion
The Stereo Integrity MAG 12 is definitely a contender in the arena of sound quality and dynamics. That said, on the value-per-dollar front, there are a number of subwoofers that are its equal or better when one takes into consideration the rather high asking price of $479 for the MAG 12. As long as your listening preferences don't tend toward a lot of complex, symphonic music, you could certainly do worse than this driver at that price, but it's your money. The MAG 12 deserves your consideration if you're looking for an attractive, accurate subwoofer for your system.