Tube life in preamp. Please help

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.

I used Telefunken in mine. I found the 6DJ8/ECC88 to sound better in the SP9 MKII , and the 6922/E88CC to sound better in the MKIII. They both lasted more than five years in standby.

I have also found telefunkens to be the tube to beat. My amprex's had a hot top end that sounded a bit unnatural.

02-25-15: Elevick
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...
Paranoid is just definition and definition maybe just another form of bs. burning amp wasn't bs it was a fact.
Don't know if anyone messed with that, but it all started around just ONE failed power tube.

The one thing that no one has mentioned is the cost of keeping tube gear on all the time. I had an ARC SP9 at one time and it wasn't drawing that much power, but it together with a pair of ARC M100 monos and we're talking $20 to $30 a month in power usage. I also had one of the M100s catch fire in front of my eyes, but in all fairness the piece had been modified. As the years have gone by I have returned to solid state equipment for the reasons that first there is really no appreciable difference in the two technologies at the high end, and that I am more focused on the music than the equipment as I grow older.