tube maintenance

I'm thining of either a tube pre or a tub amp but I have no experience with them other than hearing them in other systems.

What kind of headaches, er maintenance should I expect?
Tube Pre-amps are a snap - all you have to do is change tubes when they become noisy or fail (unless you have a balanced unit). For the most part that is a no brainer if you can wield a screw driver.

Tube amps are a bit more of a maintenance issue in that you have to bias tubes when you change them (some amps have auto bias, some have built in meters, and some require seperate meters). Some units are simple to bias, some take a bit more effort. Occasionally a power tube will fail prematurely and may take out a grid resistor which you (or your service man) can replace at minimum cost.

For your first time out try to keep you selections as simple as possible 'til you are comfortable with them.
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No one mentioned the fact that power tubes (power amp) need replacing more often than signal tubes (pre-amp)at a much higher cost; 5 to 10 times higher or in some cases higher yet. Pre-amp tubes usually will last 3 -5 years with normal used while power tubes will go 1-3 years max. So maintenance cost with tubed power amps can become quite substantial. However they are beautiful to look at and listen too and add an air of romance to the music that solid state just can not match.