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Should Class A Amps be left on??

Ok- Audiogon members need some advice here. Should Solid State Class A Amps be powered all the time? Have heard two school of thoughts on this. Apparently from what I have heard this is a moot question for Class A/B amps due to the usual low biasing of A/B Amps. From what I have been to learn so far Class A Amps should be left continously on.
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Showing 2 responses by jasonbourne52

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jasonbourne52
2,863 posts
 
My Sumo Andromeda (another James Bongiorno design like his Nine) is Class A for the first 15 watts. Then it goes to Class B for 200 wpc! It still sounds excellent at the higher power range - a mark of an excellent design! I turn it off at day's end! 
jasonbourne52's avatar
jasonbourne52
2,863 posts
 
@unsound : you are correct! A true Class A amp (like a Bedini 25/25) will get quite hot by 30 minutes after turn-on. Playing music for an hour will then lower its temperature significantly as the speaker load absorbs current. That is the mark of a true Class A circuit! If the amp temperature remains hot it is going into Class B past a few watts of Class A power! How do I know this? I owned a Bedini 25/25 for 10+ years as my "daily driver"! The Sumo Nine mentioned here is Class A only for the first 15 watts! After that it goes to Class B for a maximum of 60 wpc! Audio magazine had a test report on it back in the 80's. True Class A amps are most efficient when they are driving a load/speaker.
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