As the Pro
Real World Speaker Demo
By Mike Putnam

With so many new products on the market today, I see many people buying redundant processors, gizmos, and gadgets as they seek to improve their sound. This is not always a bad thing, but, in most cases, there is still one thing forgotten, which is the physical response of the sound system with the room.

The size, shape, and surfaces of a room all contribute to room dynamics. Acoustical treatment is often needed to reduce slap-back, reverberation, or standing waves, but before proceeding with acoustical treatment, you can greatly reduce these kinds of problems, as well as the amount of treatment needed (if any), by using a speaker that has a more focused pattern to direct the sound where you want it to be heard.

A line array or column speaker projects sound much differently than a round speaker. Advantages of this type of projection include better clarity, less reverberation, and a more consistent sound level throughout the room. The column speaker is not a new idea, but today's technology allows the ability to produce small drivers with higher power handling capabilities.

Improvement in overall sound clarity has been so noticeable in these speakers, that while installing speakers and providing sound in many different environments, we have been bombarded with questions about sound and room acoustics, which are, many times, an afterthought in the design of a building.

Here are some of the most common questions we have been asked during a demonstration:

Q: Will a stick speaker really be able to fill my church sanctuary or auditorium with clear sound?
A: Yes, it will, I say to the owners. Their anticipation builds as I plug in a four space demo rig bearing a small mixer, room equalization, and power amp. While plugging in the cords of the two speakers and power cord to the wall outlet, I explain the basic physical differences of the sound spreading out from a single source speaker vs. sound from a speaker array. When my iPod begins to play, the listener is most pleasantly surprised.

Q: How does a speaker array work?
A: Sound coming from a single point source spreads out in a round pattern and reflections off the ceiling can make a room sound very reverberant. This can make speech become unintelligible or unclear.

The sound coming from a speaker array is a wide horizontal pattern projecting vertically by only about 5 degrees, minimizing ceiling reflections.

Another huge benefit is that rather than the 6 dB drop per doubling of distance from a point source, a true array will only drop 3 dB per doubling of distance. This means that there is more even sound throughout the room as the front row is not blasted out just for those further away to be able to hear.

Outdoor performance benefits greatly from this, as you can see that this would give 100 dBs at 100 feet a continued projection of 97 dBs maintained at 200 feet.

Q: I need a sound system that is powerful yet portable. What can I use?
A: Column speaker arrays are a great way to get large sound from a lightweight box. For example, you can get a model that weighs only 20 pounds and is rated for 1,000 watts RMS. Two of these cabinets will easily fit into a wheeled ski-type carry bag for easy transport, will produce 100 dBs @ 100 feet, and will mount on a standard tripod stand.

Q: Can line array columns be wall mounted?
A: Yes, they can. In fact, some wall mount brackets not only hold the speaker securely to the wall, but they also allow easy removal for use in another room or on the road.

Q: Are specific processors required for this type of system?
A: No. Any room equalization is adequate when set up properly, just as with any other professional system. A graphic equalizer is typically used to tune a sound system for a room. The multiple bands allow for adjustment of each frequency range so that the sound you hear is as close as possible to the sound going in. This is called flat response.

Mike Putnam is co-owner and design engineer at PZtronics, a professional audio and electronics manufacturer, www.pztronics.com.