Hi, Mark:
Excellent article. I’d like to chime in on an approach to backyard audio that I rarely see advocated in publications—but one that I’ve had great success with. I work for a large audio-video-control retailer. About three years ago we made the switch from “8-ohm” speakers and amplifiers to commercial 70-volt speakers and amplifiers for outdoor sound systems where the client is looking for an immersive audio system that blends into their outdoor environment. The key advantage of a 70v system is it allows an almost unlimited number of speakers to be used-—provided the relationship between speaker power settings and amplifier's output wattage is adhered to.
We place the speakers very close together (~5ft to 6ft apart), generally on custom aluminum speaker stakes near ground level hidden behind shrubs at the perimeter of the yard with the speakers pointed into the listening area. This allows the system to "blanket" the listening area, with a near constant acoustic output through the listening area. Placing the speakers low and pointing into the yard helps keep the sound in the listening area, rather then projecting it into the neighbor's yard. A typical "large" system has between six and 25 speakers distributed throughout the yard.
We describe it as the “Disney Land Experience”, where their excellent outdoor audio system provides a near constant sound level as you walk through the park. This is accomplished by using more speakers with lower power per speaker vs. higher power and fewer speakers.
One additional advantage is since 70v is a “bus” system, where multiple speakers are wired (parallel wiring connection) into single 2-conductor speaker cable, a backyard can be wired with fewer cables compared with an 8-ohm system. Oftentimes, a yard can be wired with as few as one 2-conductor cable. This makes the installation of the speaker cable a snap. We always use direct-burial rated cable and we follow NEC electrical code guidelines to meet minimum burial depth requirements.
As far as brands go, we’ve had great success with the Crown and Extron 70v audio amplifier lines. For speakers, we most often use the JBL Control 25AV monitors. They’re excellent!
Just another angle to view larger outdoor audio systems. Perhaps the Home Theater readers will consider this approach. Or, perhaps this might make a good topic for an article in the magazine. Who knows, right?
--david