http://www.voxamps.com/forum/ VOX | Discussion Forums Topic: AC30 TB/6 feedback problem en Sat, 25 May 2013 18:28:53 +0000 http://www.voxamps.com/forum/topic.php?id=5678#post-31669 Fri, 13 Apr 2012 07:55:58 +0000 sizzlingbadger 31669@http://www.voxamps.com/forum/ <p>My first guess would be a microphonic tube. You can normally find the tube by tapping on them lightly with a pencil until you hear one of the tubes ring. I would test this while the using the bad channel and with the volume just below the point where it starts to feedback. </p> http://www.voxamps.com/forum/topic.php?id=5678#post-31666 Fri, 13 Apr 2012 01:03:57 +0000 skipos 31666@http://www.voxamps.com/forum/ <p>When I turn the volume past noon on the vib-trem channel, even with no guitar plugged in, a low-midrangey feedback loop will start. If I turn the volume below 9pm, the feedback will go away. The higher I turn up the volume, the quicker the feedback starts. All other channels are fine. I have been googling around trying to find any discussion of this, with no luck. I bought it in 2000, and it has very, very few hours on it. I rarely crank it up, so I have no idea how long this problem has been going on, or if it has always done this. Any ideas? </p>