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[Creamsnwhey]

Hello. I hope someone has experience with the problem I am having, and can gimme a hand.

My 2005 ac30 112 has just started to do this: when it's still cold, the sound will crackle a little, then become thin and gutless. It never dies 100 % but it does fade away till it sounds like its a 1 Watt amp. If I snap the standby switch off, then on again, the problem goes away. It may happen twice, once in a while. Then, after ten minutes or so, it's a non-issue, and stays full-sounding. No other switch being turned off then on seems to ressurrect the volume, except the standby, which may hint at a power problem? Tubes are Chines, old and I've played just days and days on them. I'm willing to accept that's the problem, but haven't replaced them yet. I'm just wondering if anyone KNOWS this is a tube problem, or they have other ideas.

Although the sound returns to full, I'm assuming there may be other aspects of my sound that's affected by the prob.

Tganks

[Creamsnwhey]

I want to add/augment my post by saying that this morning, the ac30 just died until I snapped the standby switch. Then it came back. So it doesn't fade away, then turn to a whisper; it also just stops projecting sound and is absolutely silent: no whisper sound, no tube hiss, nothing. But it always comes back when I snap the standby. The impression of the sound fading away must have been because the verb and trem were both engaged.

Thanks for any help....

[Creamsnwhey]

...Which is the best way to do it.

I am surprised that no one was there to say anything. Usually you can't keep folks from jumping in. It was bad output tubes. I replaced all the tubes in my ac30cc with jj tubes, and am disappointed by the brittleness/shrill character my amp's adopted. Dialing in the proper tone is different than before, but when I get it, it's...generic.

A valuable learning experience, I am going to document here for the other hopeless newbs such as myself, what I am doing with my two Voxes.

My curiosity was piqued, so I entered my ac30TB's guts to check out the tubes. It has sound issues, too, which is probably why I could score it so reasonably, with the bluebacks.

The Ei-brand el84s were pretty baked-looking, with a whitish residue in the bottom of the tubes which I saw was absent in all the new tubes. I put the original EH el84s from my ac30cc into the TB to see if the sound would change.

Horrid.

A little more "hummy" than usual. Harsh, though tighter in the lowend.

So I put the Ei's back in.They are not so loud or insistent, probably because they've aged more than the EH tubes. Anyway, I like the mellower tone of the Ei tubes.

That amp's (the ac30TB) preamp tubes are very generic, with no name or numbers on them, unless they've been worn away. Next, I'll replace these guys, six of them, or experiment with different 12ax7s in different positions.

I'm looking at "matched" pairs, quads, etc, on ebay, in the hopes of scoring some older tubes (ie. amperex, mullard) to see what those might contribute to the sound. I'm going to see about putting the new JJ el84s which are in the ac30cc into the TB, but I predict I won't be too pleased with the sound, though it will be stronger. My ac30CC just seems to have lost some of its brashness, with the jj's, which is now replaced by hysterics, with overtones of shrillness. The snottiness of the amp has been replaced with a whininess.

Sorry, I view the perfect Vox sound as a bit like a spoiled child with a really good ear for music. Sometimes he goes nyah-nyah-nyah, amd I love him dearly. Sometimes she goes OOOh-OOOh, and I'm head-over-heels for Eric's woman-tone, but this tube swap has revealed a less-than precotious loud-mouthed couch potato...if the tone of a Vox is a bit like a Child.

(BTW. I visualise the child, too; yup, in a British school uniform, with Angus' hat, and shorts, as well. He's got a skinned knee and he's tearing up alittle, but he's ready to kick someone's *Horse's Patoot* all over the schoolyard. Thanks for the digression.)

Now I'm investigating the quality of the transformers in the ac30TBs carriage, to see if I might improve my tone this way.

They have all been manufactured in England by Dagnall Electronics Ltd, and are very generic looking, with only a single lable to give information.

I don't know what I expected when I looked into the carriage of the British built Vox, but I wasn't anticipating such "cheap" looking hardware (at least as far as the three power transformer looking things appear). They might be awesome. I don't know...but I do have humming and some sounds beyond the fact that a tube amp is never silent.

I am surprised that Dagnall hardware is in a Vox, anyway, as I associate them with Marshalls. Perhaps a purchase of Mercury transformers, choke, etc, and a trip to the amp-guy at Trade-Up music for installation? I won't do that myself...it'd be wrong to so abuse a Brit-built Vox that way.

Finally, that last statement makes me wonder why I jam more on my Chinese Vox than the Korg-era Brit Vox? The inherent qualities of Chinese vs British, Hand wired vs circuit board, are topics of debate throughout gear forums throughout the world.

My British friends might get upset by this, but I PREFER the tone of my neodymium speakers to the pair of Blue bulldogs; I like the spank of the CC more. This defies logic, and the wallet, when what I want is the sound of the mid 60s. Or do I even know?

My perfect sound is somewhere between the opening riff on "I feel fine" and the dreamy, crisp power riff on that radiohead song with the "can't get the stink out, he's suckered you but not your friends" or something like that.

For this reason, I play the CC more. For this reason I am seeking anyone's advice regarding what I've described in detail, as my quest to perfect my Brit 2x12 goes on.

My two cents, and tribulations, for what they're worth. Thanks for all the thousands of responses, yo! and rock on!