#2
Don't pay someone to do it, you literally pull out the valve and push in the new one, some amps/valves screw in, still a simple job, some amps have covers over the valves to keep them in place, still a simple job to do though.

If you took it to a guitar shop, they'd probably charge you £20 or so to fit the valves for you, but that really really is a waste of £20.

Valves themselves vary hugely in price.
"In modern music, a lot of people are really stuck on the example, asif it were the idea. It takes millions of examples to articulate an idea, so don't get stuck on the f*cking example." - Joshua Homme, 2008.
#3
Hotrox is the best place to buy actual valves from. With regards price, I paid a tech £20 with a complete rebias and test on all the valves (including preamp).
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Quote by Kensai
I must be even further in the closet then
#5
Replacing power valves is a very easy job anyone can do. its just a matter of pulling the old ones out then replacing with new, but thats not the whole story if you want things done properly.

Biasing power tubes is a little more hassle and well worth paying a few quid to get done if you can find someone reasonable with their prices.

You can just not bother with the bias but be well aware of the fact that the tubes wont have the right current hitting them and will either run hot or cold. Both hot or cold will affect the sound and life of the tubes. hot = less life in case your wondering...
ESP M-1 - Dimarzio Super3
Ibanez RG3270 ToneZone/Blue Velvet/Paf Pro
Ibanez RG1527
PRS CE22
Mercer Blackmachine Replica

Diezel Herbert
Diezel Einstein Combo
TC GMajor

Gain Wh0re and Diezel Mafioso
#7
I see, I see, you didn't mention that. Yeah, if you want them properly biased and stuff then it's worth the money, I still think it would be about £20 on top of the price of the valves to have someone do it though, maybe slightly more, it definatly wont be anywhere close to £160 though so dont worry too much haha.

I've always bought Electro Harmonix valves when mine need replacing, some places sell them in 'matched pairs' but I've never bothered taking them anywhere and having them biased properly, and they sound fine to me.

Then again valves and their biases isn't really my area of expertice.
"In modern music, a lot of people are really stuck on the example, asif it were the idea. It takes millions of examples to articulate an idea, so don't get stuck on the f*cking example." - Joshua Homme, 2008.