Vox AD120VT

[Blueswaite]

I have this amp but when I play my Ibanez Artist with Seymour Duncan Lil 59 or my strat on the g and b string I get a fairley loud ringing tone after I hit the string.. I have lowered the pickup and in the amp went straight into the effects return to just use the power amp and still get the ring. Tried a 31 band eq in front and in the loop to try and take it out to know avail. Any ideas. At first I thought the preamp tubes might be going, but I believe when you go strait into the effects loop it by passes them Any ideas are welcome.
Thanks

[TS808]

I have the AD60VTH (the head version of the 60-watt) as well as an AD50VT 212 and have never had this problem. What you're describing I had never heard of before.

I would post the question on the discussion forum at www.valvetronix.net
That site is THE best resource for these amps and Voxman can be very helpful.
Give it a shot.

[Blueswaite]

Being doing some checking and the problem seems to be a microphonic tube. Going to change the tubes to Groove Tubes 12AX7-C.