So my Peavey Valveking has served me quite well for the past year or so, and within the last few weeks the gain has started to thin out and lessen. I was playing it today and with the gain all the way up and the boost switch turned on, it was basicallys a very Zeppelin-y sounding gain. I figured this was because the tubes were dying, and needed replacing soon.

Well just a minute ago, the sound level dropped a lot. Like cranking the amp all the way up achieves slightly louder than bedroom levels. I've taken all the tubes out of the amp and none of them look burned out, so I don't know which ones need replacing.

Are these common symptoms of one type of tube dying, or should I just replace all of them? If I replace all of them, I won't have enough money to replace all of them at once, so which should I replace first, Power or Preamp?
I'd retube the entire amp since you've had it for @ 2 yrs. Eurotubes.com has complete retube kits for the Valveking
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yea just do it clean man. once one goes bad the rest will follow.
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