Solid state power amps.; on or off?

Yea Craig, if you ever have a chance to pick up a Proton, they are ausume. Best piture tube made (Hattachi). I got mine at a close out dealer for 70% off and it was still over $1000, but that was the first and only issue I've had. Now it just needs to last another 13 so that HDTV finds it's place. J.D.

I have started turning off the Musical Fidelity SS amp attached to our mini system due to the power problems in California and it does not sound as good at it did before (when left on 7/24), not nearly as much detail at low listening levels which is how I use it in a near field setup. I still leave the CD player on as it does not draw much current.

I left a Cello Duet 350 powered on for most of eight years -- only took it down for vacations, renovations, cable changes, etc. Bought it in 1992. Now it runs in my home theater and is powered up only when the system is active (maybe 4 hours a week) -- but it certainly suffered no ill effects. One caveat is that electrolytics have a rated life -- so they will age more quickly if the amp is left on; the semiconductors, it seems to me, benefit from being left on (fewer transients and fewer temp changes). Since the amp is now nine years old, its capacitors should be replaced. I used to manage service for $5-15 million (per copy) mainframe computers -- and the absolute worst thing that customers could do was to power them up and down -- the process inevitably shook out the weak components. A machine that had been powered up for months, once powered down, was a good bet NOT to come back up without some expensive repairs. Those experiences have always left me convinced that electronics (w/o moving parts) are probably more reliable if left on.

Technology has moved on once again. Capacitors are one of the "active" components that benefit from being left on as long as they are not "cooking" inside of a "hot box". When electrolytic caps are not used for an extended amount of time, they first discharge and then begin to dry up. When power is then applied to the unit, there is a MAJOR in-rush current to the caps in order to "fill them". Until they are "filled" they present a near short to the power supply. It is at this time that many caps or other components in the power supply are stressed and "pop" under the instantaneous but large load demanded. Keeping the caps fully charged will cause less thermal stress along with greatly reduced risk of dielectric damage from internal arcing. This is why "techs" use a variac to SLOWLY power up old equipment. They are letting the caps "reform" gradually instead of blasting them with the massive surge that they would normally see upon "firing up". Sean
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Just talk to Classe this morning, and they said the same thing that I asked a month ago which is "everything should be off, and turn on two hours before listening". I'll ask my dealer tomorrow. DT