Tube life in preamp. Please help

don't leave tubes on stand-by if you want to save your equipment and your dwelling. it's dangerous no matter how well tube electronics are designed. if you're not watching your equipment or go to bed you must turn that off.

A note about tube's being damaged by "current in-rush"...I've owned tube guitar (old low wattage stuff, high wattage English and US amps, etc.) amps that kept their preamp tubes for DECADES and were turned on and off thousands of times with and without "stand by" circuits with...here it comes...ZERO preamp tube issues. I doubt hifi amps get the abuse guitar amps suffer in their natural state (do you overdrive your preamp tubes to distortion for several hours while their in the same box as your speakers?...no you do not).

Well, Wolf, i once re-wired point to point VTL tube amp that started burning in front of my eyes, but I'm glad you're always holding premium cards that you don't have to fold.

Czarivey-You are a bit paranoid, aren't you? Not too many amps will "burn in front of your eyes" unless you mess with them...

Standby was created for a reason and generally speaking it works quite well at extending both tube and equipment life. An amp that burns up usually does that as soon as you turn it on, not after being on standby for 4 days or 400 days.

Yes, I do turn off gear when I'm not going to be around for a couple of days but never for shorter periods.
Preamp tubes should last longer in standby by avoiding the current rush. Many NOS 6922's can last 5000 to 10,000 hours.

The ARC SP9 series of preamps do NOT have your typical "standby" mode that some preamps have. Most "standby" modes reduce the voltage to the tube(s) and only keep the heater warm.

The SP9 preamp has only an on & off and a mute & operate toggle switch. The mute switch just mutes the output, but keeps full current to the tubes.

I agree with everyone above, if the SP9 had a real standby circuit, but it doesn't. I turn my SP9MKII on 30-45 minutes before I'm really ready to use it, then it takes an additional 30 minutes or so to warm up to full potential.

If even you keep it on full time, the tubes should last 5000-10,000 hours so you would need to replace them once a year or so.