why are preamp tube life much longer then poweramp tubes

[Forrrest]

Why is preamp tube life much longer then poweramp tubes? Preamp tubes just never die, don't they get pushed for distortion a whole lot more then poweramp tubes?

[12XU2A3X3]

i would guess physical wear on components in power amp tubes were voltage is anywhere from 300x to 30x what preamp tube utilize would be a factor.

[GardenoftheDead]

The preamp tubes barely have any current going through them. The power tubes are doing all the work.

[univalve]

because they are no power tubes.

[goroth]

I'd guess like Garden said it's too do with the current. An common analogy is with water pipes - voltage is the difference in water pressure at two different points in the pipe (i.e. the potential for how much water will flow) and current is the actual rate of flow of the water. With a high enough flow rate (current) and a small enough opening (resistance) you can do all sorts of damage to stuff. It's the actual flow of water that's killer, not the potential difference (although the two are of course inseparable).

I know if I put the wrong current limiting resistor in a pedal with an LED I blow up the LED, but if I change the voltage it gets more or less bright. Same things with an electric shock - you can survive substantially high voltages, but you can't survive much current. Tubes are like people. Haha.

Preamp tubes don't have much current flowing through them.

PS: all of the above is super true. I got 49% in my final exam in first year electrical engineering before making the wise decision to study politics instead.

[multi_s]

i think it's because power amp tubes cost way more (in general) than pre amp tubes. So in order to maximize profits, they just make power tubes more prone to failure.