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Amps and Preamps has standby, but should I turn them completely off?

Hi guys, I know there has been discussions of this and the overall consensus seems to be leaving the Solid State amps / preamps on (or standby). I have a Parasound A51 that runs pretty hot. The heat sinks are hot to touch after running them for 2 hours. Ever since I move them to the 2nd floor (gets hot in the summer), I worry that they'd run too hot so I turn them completely off (by switching off the surge protector) after each use. Note that standby mode doesn't solve the heat issue -- it still generates a significant amount of excess heat. 

My question is:
1. Does turning them off after each use shorten their life?
2. Does turning them off increase the probability of failure?
3. Does the excessive heat damage them in the long run by leaving them on?

I am not too worried about warm up time because I use them 2-3 times a week tops. I just don't want the excess heat on the 2nd floor since it's already much warmer than the 1st floor. 

Thanks!!
angelgz2
gs5556
769 posts
 
Your amplifier has a soft start circuit which limits the current inrush through the power supply. Therefore there is no problem cycling the amp on and off as needed. 
kijanki's avatar
kijanki
3,575 posts
 
Czarivey, life of capacitor is reduced by factor of two for every 10degC increase over temperature that life of capacitor was specified by manufacturer.  For instance capacitor rated 5k hours at 85degC will last 2.5k hours at 95degC 1.25k hours at 105degC etc, but also 10k hours at 75degC, 20k hours at 65degC, 40k hours at 55degC.  At 25degC (room temperature) it would be 320k hours (37 years).  Different manufacturers define end of life differently but often it is 200% of rated ESR.  When capacitor dries out ESR  (equivalent series resistance) increases.  Increase of ESR produces, with electric current, increase in temperature.  Increase in temperature produces increase in ESR leading to avalanche effect and explosion. 
czarivey
4,494 posts
 
So the life in my class D amp is practically infinite. It runs perhaps at 30 Celcius tops.
kijanki's avatar
kijanki
3,575 posts
 
Czarivey,  will you last 40+ years?

kijanki's avatar
kijanki
3,575 posts
 
Timlub, I'm not sure why keeping them charged stops them from leaking.  Perhaps some capacitors are not properly sealed, to start with, and would eventually leak.  Keeping them on will most likely increase their temperature (since electronics dissipates heat) drying out electrolyte faster, hence thickening it (and reducing capacitors' performance).  Company I work for has a lot of obsolete electrolytic caps in stock,  often 30 years, and I never heard of any of them leaking.  They are unusable, in my opinion, but it is not my decision to toss them out.  Keeping fully charged might extend life of some batteries, but not capacitors AFAIK.  The only negative effect turning electronics off is reduction in breakdown voltage of the aluminum capacitor.  Without voltage electrolyte eats out dielectric - aluminum oxide, reducing breakdown voltage.  Presence of voltage rebuilds dielectric.  We're talking  >5years of keeping gear unpowered.
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