My original background started in television back in 1957. At that time everything was tubes, with transistors sneaking into the mix over the next few years. With tube equipment, they were never turned off, other than repair. Many tube circuits, would drift with changes in temperature, therefore, all of the electronic rooms were kept at 68 to 72 degrees F. As the TV industry grew into solid state circuitry, the same standards of temp control and policy of 24/7 powering remained the same. I ran a TV production facility for 17 years, and the only thing that we ever turned off, were the
CRT monitors.
I am not sure where I heard it, but it was widely accepted in the TV industry, that most solid state circuitry that fails, will do it in the first 90 days of continous use. There after failure rates are rare for the next 10 to 14 years, as long as the 68 to 72 degree at 50% humidity or less, standard was maintained.
In Theatres where amp racks and
dimmer racks are maintained under those standards, I can see no reason for powering them down. There was a chart, that I no longer have, on how failure rates increase with ambient temperature. It is almost shocking how quickly the rate of failure increases with just small changes above the quoted temperature.
That being said, I turn off all of my electronics at the
theatre where I know hang my hat. We are in the lightning center of Florida, and our building is a city owned building where temperatures vary with supervisory attitudes.
Our
house light
dimmer is powered 24/7, but I built it from some 1970s Electro Control modules using dual SCRs. I also have two oversized fans in the rack. One comes on anytime one of the channels is brought to more than 30% and the other is turned on by an internal thermostat when the rack temperature exceeds 80* F.
Tom Johnson
What are the hazards of an amp just sitting on not doing anything if anything, aside from the "heat" and electronics run better cool, as pointed out earlier?
