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tube amp auto bias and general tube amp use

Hello,
My system comprises of the Ayon Sprit 3, Ayon CD1sc and PMC OB1i speakers. The Ayon is my first tube amplifier and although I was never afraid of the maintenance associated with tubes (I was rather intrigued), the Spirit 3 has auto bias so all I have to do is press a button.

Still, I have some questions regarding use of this auto bias button and general tube amplifier use since this is very new to me. Please forgive me if these questions sound rather banal, and I know I could also forward these to Ayon itself but I would love to hear from experienced users on these forums.

So here it goes.

1. The manual for the Spirit 3 states to press auto bias once a month. OK, but is this if I listen everyday? Due to my busy work schedule I often listen only during weekends. So do I press auto-bias less than on a monthly basis? Can I press it more often? Will it damage something if I press it once a week? Will it be better or worse if I press it after every turn on?

2. Is it ok to turn the amp on for, let’s say an hour, for a quick listen. Can I do this a couple of times per day? Or is it better just to leave it on for 6 hours even if the amp will be inactive for 2 hours or more? How does all this affect the tubes and their life?
_________

My previous system was a Cambridge Audio 840 which I found a little bland for different types of music, and after a listening session with a Bryston (2BSST2), Naim (Supernait) and Ayon, the Ayon had that edge and especially after I brought it home and settled in with it. Soon after the CD1sc arrived. Love it.

Thank you for your advice,
Norbi
norbi
bigshutterbug
383 posts
 
Once a month should be fine as long as your tubes seem to be stable. I would not suggest biasing it every time you turn it on. My Spirit II is not auto bias, but it is quite stable with a good set of Black Treasure KT88's. It is not that critical that each tube be within a few points of each other. You will not be able to hear a difference if they are off by just 10 points or so. Have you tried rolling different 12AU7's in it yet? The amp sounds even better with some nice NOS Amperex Hollands or Mullards. The Amperex 7316 is a real eye-opener in these amps too. Enjoy!
wolf_garcia
6,696 posts
 
Modern tube amps are a lot more rugged than one might think, and one of the nice things about 'em is if after thousands of hours of use a tube gets old, you simply replace it. Also, I seriously doubt that any harm comes from hitting the re-bias setting more often...although as Bigshutterbug said, it's simply unnecessary. I bought a voltmeter even though I don't really need it (I use an "ez bias" amp with LED indicaters) just because it's interesting.

A note on tube amps...I dragged a couple of Fender Twin Reverb amps around during most of the 70's (4 6L6 tubes facing so all the heat goes up into the chassis!), as well as using a really old white Bandmaster, A Mesa Boogie Mark 1, a Marshall combo, etc., and they always sounded great and were extremely reliable. I mean extremely! I currently use a 6V6 based "boutique" all tube combo daily now and if you think about the vibration and heat those things suffer, you sort of get the point. I realize hi end home audio amps are a different animal (less beer spilled on them usually, and baggage handlers don't drop them as much), but not that different really.
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