Study Hall

Supported By
ProSoundWeb

Unplugging From AC: Why Playing On Battery Power Alone Can Be Useful In 2022 (& Beyond)

Taking advantage of a rapidly growing slate of options to effectively drive smaller-scale sound systems as well as instrument amps (and more) without electrical power. (A downloadable audio version of this article is also available.)

SIDEBAR:

Set The Flux Capacitor To 1974…

Power is a wonderful thing, isn’t it? Back in the days of analog power supplies and incandescent lamps, my band would often use a pair of 50-amp/240-volt outlets to get the 200 amps at 120 volts needed for our shows. Now, we were just a cover band in the mid-1970s, but I had a 50-kW lighting rig that consisted of 48 old-school 1,000-watt PARs with 500-watt pin spots with dimmers that I designed and built myself.

Meanwhile, the sound system included a rack with 5,000 watts of old-school Dynaco and Heathkit power amplification that was very hungry for AC power. We couldn’t even think about plugging this rig into just a few 20-amp wall outlets. It required a direct connection into a club’s electrical service panel with 100-amp wiring. Ah, those were the days….

Moving along to the 80s, I did a two-piece act with a guitarist that was much more modest in terms of power requirements. It only had a single stereo 1,000-watt amp (still with an analog power supply) plus a few 300-watt spots. So, if we didn’t do anything crazy, it would run (just barely) from a single 20-amp wall outlet. Still, if I got out of control with my Mini-Moog playing key bass, I could trip the circuit breaker. Oops…

Over the subsequent decades I ran the sound for hundreds of live and broadcast shows of all types, many of which required a large generator or 3-phase power on cam-lock connectors. But I noticed that as the years went by, the AC power requirements got to be less and less.

Of course, one of the biggest watt-reduction technologies was the introduction of LED lighting instruments. They’re handy not just because you could attain any color you wanted without the need of gels, but their power requirements were about 10 percent (or less) of incandescent lights. An LED lighting instrument that only needed 50 watts of AC power would easily replace a 500- or even 1,000-watt PAR. Plus you didn’t burn your hands changing lamps.

At the same time power amplifiers were making great strides in reduced AC power requirements, to the point where a small rack of really powerful amplifiers could run on a single 20-amp outlet in many cases. And the amplifiers also lost a lot of weight in the process, thankfully. I still have a rack of four Crown Macro-Tech 2400 amps that tests your back every time you move it, and it’s currently powering a wall of 80s vintage concert cabinets that weigh 420 pounds each (these components are pictured here).

This kit now resides in the kids’ game room, and I’m not moving it anywhere. And the kids have to be careful to power up the amps one at a time or it will trip the 20-amp breakers providing them with AC. I’m glad the good old days of heavy metal aren’t coming back. I don’t think my back could take it…

Study Hall Top Stories