#1
Long story short i was recording on my jcm800 not too long ago and even though i had the volume knob rolled down so i could get a clean sound, it started to distort. It was working fine before i dont know what happen have any ideas whats wrong?
#3
anyway i could check this? i heard of taking out a power tube one by one to check which one it is but i dont know if that sounds safe i feel it'd just break my amp
#4
No what you can do is the pencil tap test. There is a stack more information on this test and how to do it properly in the forums just do a search. It is safe and will give you a good idea on which tube is playing up. But if you don't feel up to it then take it to a technician. Hope this helps I was in a little rush when I wrote the other comment.
#5
thanks i appreciate the help. I've heard of the pencil tap test i thought that was to check if pre amp tubes are microphonic?
#6
Any tube can go microphonic but that isn't the only way they can fail and the tap test won't identify any other type of fault. You should always have spare tubes. A full set of power tubes and at least one spare preamp tube. When something like this happens you just try your spares and identify the fault by a process of elimination. Had you had spares you could have diagnosed the fault in less time than it took to make this thread.
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