#1
Hey guys,

I have a Vox Valvetronix AD50VT. It is a hybrid amp; it contains two tubes in the preamp but the full amp is a solid state circuit.

Anyways, today I got a new guitar and Fuzz effect pedal. So I plugged it into my amp and maybe a few minutes in I hear this really high pitched screeching sound and then everything just kinda stops working and gets really quiet. So I shut every thing down and then reboot it all back up.

So, now, my amp, which I have NEVER even gotten close to turning all the way up is relatively quiet turned as far up as it can be.....

Im wondering, is it possible this is because one of the tubes went out?

Or was it something else? My second guess is it was the Fuzz pedal.
Last edited by aaronob at Feb 16, 2009,
#2
i doubt it. the tubes don't have much to do with the circuitry in the VTs, but it's possible, i guess.
I'm putting my GAS on hold
for a couple months in order to pimp my ride.


Don't judge me.
#3
Quote by theoreticmusic
i doubt it. the tubes don't have much to do with the circuitry in the VTs, but it's possible, i guess.

Isnt that what tubes sound like when they go out though? A really high pitched screaming?

And also, would the circuit still function at all even though one of the tubes is out?
#4
I'm not all that familiar with the innerworkings of the ADVTs, but that's sorta what microphonic preamp tubes sound like. turn your amp on and tap the preamp tubes with the eraser end of a pencil. if that sound comes through the speaker, then replace the tubes.
I'm putting my GAS on hold
for a couple months in order to pimp my ride.


Don't judge me.
#5
could be the output transformer
"If you're looking for me,
you better check under the sea,
because that's where you'll find me..."
#6
I have a Vox Valvetronix AD50VT. It is a hybrid amp; it contains two tubes in the preamp but the full amp is a solid state circuit.


First off, no, it's only ONE tube, and it's part of a .5 watt power amp that daisy chains into the full solid state power amp. The wattage increase is done in the solid state section.
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#7
Quote by gwitersnamps
First off, no, it's only ONE tube, and it's part of a .5 watt power amp that daisy chains into the full solid state power amp. The wattage increase is done in the solid state section.

Oh ok. My bad. How would I go about accessing the tube to test it, like theoreticmusic suggests? Is it easy access to it or do I need to tear the whole amp apart?