Tube Preamps Should Have This Feature

@invalid

Thanks for your reply. Really. That means you are running them 8,700 hours a year.

I have been told that tubes… particularly power tubes age more slowly when on but not in use. Maybe that has something to do with it.

My Audio Research gear recommends tube changes after 3,000 hours. When I do this I hear a bit of and improvement, as in the older tubes were starting to roll off a little.

What kind of gear do you have?

@ghdprentice  power tubes do age faster, but those are in the output stage of an amplifier, not in the power supply section usually, though some power tubes can be used as rectifiers and in some regulation positions.

@invalid 

That makes sense the lasting longer would not extend from power tubes to rectifier and smaller tubes.

So, what is your preamp / DAC.

@ghdprentice my preamp is space tech Lab qa112 and my DAC is also space tech Lab DA24/196, I'm using a separate power supply with the preamp called a super rectifier STR104 with two 3b22 rectifier tubes each rectifier tube has a 6amp heater current.

Thanks. Interesting. I had not heard of them. Lots of tubed equipment. They must use the tubes conservatively to get so much mileage out of them. Always good to see different audio companies.