The year was 1877, and Thomas Edison played back “Mary Had a Little Lamb” on his newly created tinfoil recorder. That basic model of a transducer driving a horn has been the basis for sound reproduction system design ever since. The sound waves spread out in three dimensions, constrained only by the shape of the enclosure and the acoustics of the room.

FAST FACTS Applications Theaters, Houses of Worship, concert halls Key Features 12 2.2-inch drivers; horizontal 160-degree dispersion range; 300 W continuous long-term power handling; designed for use with Bose Panaray digital controller or plug-in EQ card and subwoofers such as the Bose MB4 Price Contact your dealer Contact Bose Professional Systems 877-428-BOSE pro.bose.com PRODUCT POINTS PLUS Well-controlled dispersion pattern Clear, articulate reproduction MINUS Limited frequency range Requires subwoofer for normal music reproduction THE SCORE A quality implementation of the line array design for smaller venues

A different paradigm emerged with the advent of line array loudspeakers. The line array emits sound from, well, a line instead of a point source. The cylindrical waves that are generated spread out in essentially two dimensions. The sound level consequently dies off far less over distance. The level doesn't have to be as hot in front to provide coverage in back, and there is significantly less interaction with the surrounding acoustics. So many drivers work in concert to provide coverage that no one driver is putting out as much energy as, say, the tweeter in a traditional three-way system. This, coupled with the more controlled radiation pattern, means that the system is likely to be operating much further below the feedback point than a traditional system.

Line array loudspeakers and their variants have become a familiar sight in large concert venues for these reasons. And the subject of this review — the Bose Panaray MA12 Modular Line Array Loudspeaker brings this concept into a unit that is suitable for smaller PA applications, such as churches and concert halls.

Features

The MA12 is a loudspeaker using 12 2.2-inch drivers and handling up to 300 W continuous power. It offers a maximum acoustic output of 113 dB at one meter with a frequency range of 155 Hz – 12 kHz (-3 dB) and 100 Hz - 16 kHz (-10 dB). The MA12 — a true line array — has drivers radiating sound over 160 degrees in the horizontal plane, while providing vertical coverage in a band of constant height. They can be complemented by the MB4 Modular Bass Loudspeaker for more low end, and a variety of mounting options are offered.

MA12 loudspeakers are designed for use with the recommended loudspeaker EQ curve resident in the Bose Panaray system digital controller or Bose amps in conjunction with a MA12 speaker plug-in EQ card. Use of either the controller or EQ card allows crossover with a sub, such as the Bose Panaray MB4 bass cabinets.

The MA12's aluminum enclosure measures 5.1 x by 4.2 x 38.7 inches and weighs 20 pounds per unit. Connection to source signal is provided by two parallel-wired NL4s and one two-position barrier strip. The MA12 is available in both white and black finishes.

In Use

I first heard the MA12 speakers at a church located in a recently renovated historic movie theater. There had thusly been problems getting coverage of the seats nearest the stage from the loudspeakers that were flown overhead. The band had begun using in-ear monitors, and these seats were getting almost no direct sound at all. Two MA12 units, placed on either side of the stage, provided even coverage of the front rows at a reasonable sound level without unduly interfering with the sound from overhead. They even helped to localize the sound with the band at stage level.

It occurred to me that these might be a good solution to a problem that had vexed a recital hall. The room, with 500 seats, rarely requires PA for music, but occasionally needs amplification for lectures and other spoken commentary. The room's sound reinforcement system as originally specified had a pair of conventional speakers mounted at ceiling height (around 30 feet) between the acoustical clouds over the stage. This “hang-and-tilt” approach minimizes the differences in speaker-audience distance from front to back, and is in widespread usage for installed sound. The hall, though, exhibited the two main shortfalls of this approach. Firstly, the wide dispersion of traditional speakers means much of the sound is not headed directly to the audience. Secondly, the sound tends to localize at the loudspeaker, which in this case was 30 feet above the stage. This is not the optimal state of affairs in a venue that is principally used for acoustic music.

Serendipitously, an overly exuberant experiment resulted in a couple of blown drivers, so we took the opportunity to mount the replacement speakers in the organ loft. This put them at the sides of the hall, only 12 feet from stage level. This helped to put the image back in line, but we were still dissatisfied with the clarity of the spoken voice. Too much of the sound still went up into the space above the audience, causing reflections that complicated diction.

A local dealer offered the chance to try a pair of dual Bose MA12 speakers with the matching MB4 bass cabinets and the Bose Panaray System Digital Controller. They were set on stands at the sides of the stage, near the place where they would need to be mounted. They were then put to a most difficult test: two faculty with strong accents who just happened to draw a crowd with many older patrons.

The results were fantastic! Several patrons commented on being able to finally hear what the performers were saying. There were no complaints about the sound being too hot in front or too low in back. A permanent set were then installed and augmented by the Meyer Galileo 816 processor, since the system needed the additional I/O and the ability to control the unit over Ethernet.

Several options for mounting speakers of this unusual shape were considered. I thought that the tall, slender MA12's might be able to hide among the organ pipes, but I didn't push that idea too far. So they were mounted at the sides of the stage as planned. One word of caution is in order here: while these speakers are quite sleek in appearance, they are still heavy! The dual MA12 columns weigh a bit more than 40 pounds each, and their length produces a good bit of leverage against the mounting brackets.

The MA12 units were first tried by themselves, fed directly from the mixer. The speaker again was a foreign artist with a strong accent. And, again, the response was uniformly positive: “Best sound I've heard in a long time!” and “Every word was clear!”

The full system was then hooked up. The MB4 bass units were placed on the sides in the organ loft, where the former system was located, and wired in the Galileo. A few favorite CDs were played to verify the filter settings and awaited the next test.

An annual jazz festival began two days later. This afforded the opportunity to try some music. The MB4s extend the system's frequency response down to 40 Hz, plenty enough for the reinforcement required by ensembles. The opening concert was a six-piece jazz combo and a seven-piece saxophone orchestra. The PA requirements for jazz are very much the same as for spoken voice — clarity and articulation are of primary importance, and I already knew that the MA12s could deliver.

One thing quickly became apparent: Localization was far more critical with less sound bouncing around the room. Introducing any significant level in the MA12s with an instrument on stage generating just about enough sound to be heard on its own pulled the image straight over to the loudspeakers. Time to set the delay! This setting proved to be far more critical than it had been with the previous conventional system. We eventually reached a setting that worked through most of the hall — keeping the image centered on the players where it ought to be — and sat back to listen.

That's when I made the most impressive discovery: I was able to pan the soloist's sound with remarkable precision by properly setting delay. I consider jazz as essentially acoustic music, and I've always hoped to have the apparent size of the group mirror the actual size. This goal was achieved with the Panaray MA12 system.

Summary

It's true that localization will never be perfect for everyone in a room, whether it's five seats or 500. But the clarity of the Bose Panaray MA12 system and the limited interference from reflections bouncing around the hall allowed for a precision of imaging and placement that I had only dreamed of.

The lingering thought at the end of this evening of jazz was that this new PA system is truly something different. The sound is more controlled than our conventional system, and the clarity is remarkable. The Panaray MA12 system looks and sounds like the perfect solution for a troublesome hall.

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