i just got a vox ad50vt valvetronix and it has a 12ax7 used as a power tube and im wondering if anyone knows if i need to service it like a tube amp (ie changing the tube and re-biasing ect)???
Nope, no servicing needed. I don't think you even need to change the the tube (its soldered right in...can't remember)
I can't even get to the tube in my (blue series) Valvetronix without a screwdriver...
Quote by sempri_fi
really, thats not how mine is.

back of the amp enclosure... Its not a closed back cabinet
No, it only runs on like one watt.

And yours is different, since it's a silver series. Mine's blue.
You can change the tube. You can get slightly different tones from different tubes (well, in other amps, anyways; I'm not too sure how it effects the sound in the vox amps). But you shouldn't need to change the tube for a couple of years at the least.
i wouldnt change the tube until you need to. the tubes that come in them are some of the best you can get.
Quote by Tiamat
dont buy an amp, amps are just stupid.

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oiled... i like the feel of oiled wood in my hands... wow, that was homosexual...
^It's usually a preamp tube, but Vox uses them as poweramp tubes, since they only nees a small current for the Valvetronix system.