This amp has been back to two techs but as it was an intermittent occasional fault neither could find or replicate the fault.
After playing for a length of time, the amp would sometimes lose volume and distort. Please dont tell me its the known thyristor problem as its not. the amp still produces sound but distorted. sometimes wiggling the amp fixes it , maybe a dry joint somewhere, sometimes it doesnt. Today i tried it again and when it started distorting i switched off, removed the first power valve and switched on again. it actually sounded ok. I switched off, replaced the first power valve and removed the 2nd valve, this time it was very distorted. I then tried swapping the valves in each position. the trouble is its still intermittent but it does seem to me the valves are working ok but something about the first position is causing a problem. I saw
@voxman had a problem with one of his valve sockets so im guessing i may have the same fault. my soldering skills are not great (more due to bad eyesight) and it looks as though it involves removing and disconnecting the pcb to get to the sockets so i think its back off to maybe a different tech. just wondering if im on to the right idea with this or is it unlikely
Comments
If it isn’t to do with the valve socket it could still possible be a problem with the OT. I had a LC15 for repair a while back which did something similar and turned out to be an intermittent partial short on one side of the OT winding - it ran fine with only the other valve in, and most of the time with the one on the faulty side, but would intermittently drop in volume and sound very distorted.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein