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My ? is do you keep a tube amp in stand by mode all the time or turn it off. I do try to us it everyday .
The head unit is Traynor YCS100H Custom Special 100H that  iam using right now

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JanVigne    27

IMO the only reason to leave a tube amp powered up 24/7 is that you really, really think it performs better that way.  That makes more sense for a home audio tube amp than for an instrument amp.  

 

Two things to discuss though.  

 

1)  Tube power amps typically use an output transformer to work as an impedance match between the high output impedance of the tube(s) to the low load impedance of the speaker driver.  Transformers can take a while to fully warm up which could mean the amp does perform better after a warm up period.  Though about one hour's warm up should be sufficient for most transformers.

 

2)  Depending on how your amp was designed, the tubes are slowly wearing out even at idle.  Does the stand by setting actually lower the Voltage going to the tubes to extend life?  Or, does is simply disconnect the speaker outputs to silence the amp?  If it reduces Voltage, you can observe a slight reduction in the brightness of the tubes when you place the amp in stand by and a hotter looking tube at normal usage.  

 

If your amp runs fairly hot at idle/stand by, then your tubes are wearing out rather quickly.  A very conservatively designed tube power amp should idle at a temp that would allow you to place your hand on the output transformer(s).  If you can't do that with your amp, then your amp is burning tubes as it sits.  One thing to keep in mind is tubes begin to age the moment you put them in service.  You can certainly find less expensive tubes but, if you're running some NOS or exotic tubes, you might not want to waste your tube life on a silent amp.

 

Finally, like an incandescent lamp, tubes (and related passive parts) generally stop working when they are slammed with a full 120VAC at start up.  If your amp has a soft start circuit, the chances of this happening are virtually nill and tube (and parts) life will be greatly increased.  If your amp does not have such a circuit, you might want to consider adding one.  

 

https://www.google.com/search?q=soft+start+circuit+for+a+tube+power+amp&rlz=1CAACAY_enUS752&oq=soft+start+circuit+for+a+tube+power+amp&aqs=chrome..69i57.10196j0j1&sourceid=chrome&ie=UTF-8

 

A rather old but still useful concept for a soft start is to place a thermistor in line with the incoming AC line and the power supply;  https://www.google.com/search?q=thermistor&rlz=1CAACAY_enUS752&oq=thermistor&aqs=chrome..69i57.8095j0j1&sourceid=chrome&ie=UTF-8

 

McIntosh used thermistors for decades in their original tube amps, which were well known for their reliability and longevity.   A qualified tech can probably install such a circuit though you might want to ask about future warranty repairs prior to modifying your amp.        

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