So I got a Vox AC15CC1 for my birthday this past April. It's my first tube amp and I love it dearly. From day 1, I noticed that one of the EL84 power tubes is a lot dimmer than the other, even at full power. Once again, I am completely ignorant when it comes to tubes, so I assumed it was normal.

However, just recently, I have noticed an annoying and very apparent crackling static noise that comes with any sustained note, some more than others. The more gain I give it, via the Top Boost knob, the more apparent and obtrusive the static is. This, needless to say, is very annoying and very unsettling.

I have no idea if these issues are related, or if they're even issues at all. For all I know, this could be totally normal. I just ordered a pair of JJ EL84/6BQ5s yesterday, hoping to remedy the problem, but that could've been a total waste of money.

If there's any more information I can give, let me know.

Please UG, relieve me of my ignorance.

it is normal for one valve to be slightly lighter than the other, but it shouldn't be a drastic difference. Maybe a speaker change is necessary?
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DBZ guitars, love'em. Especially their Les Piccolo model.
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it is normal for one valve to be slightly lighter than the other, but it shouldn't be a drastic difference. Maybe a speaker change is necessary?

That's what I was worried about... I don't really have a ton of cash to spend on a speaker.
If nothing else, the JJs may at least be a better tube than what's already in them. There's a pretty solid chance that it's at least an upgrade.

If it's a Class A amp, it'll have some static no matter what. Amps that are wired better (or use more expensive components) will be quieter, but nothing will be silent if you jack the gain up all the way. Well, nothing short of a handwired amp with high-end cables and a well-wired guitar in a room without any sort of electronics.

Now if the gain and volume are at a fairly managable level and the static is too loud, then it sounds like you have a loose connection somewhere. The tube is really unlikely to be dead, but it might be faulty. Also check to make sure all tubes are seated well, and the speaker connections are solid. Also check the guitar cable you're using.

If the static is really loud, and none of the things I mentioned help, and you didn't drop the amp, then it sounds like you might want to talk to the guys at the shop where came from.

Overall, the amp is very quiet. There's hardly any hum, even with Top Boost at 3 o'clock. The static only comes in with sustaining notes. As the sounds trails off, it starts crackling and sputtering. The amount of this sputtering increases with gain, but there is no static that is present all the time.
Tubes make that noise sometimes when they are going bad or when they get turned on and off a lot. The tubes you ordered may solve the problem. I'm not familiar with the tube compliment in your amp but it could also a pre-amp tube making the noise. Capacitors in the amp are supposed to filter out that kind of noise and can go bad as well. The poster who said to check the connections in the guitar and your cord is right on as well.