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Help with a new Tube headphone amp blowing fuses

Received a new headphone amp this week to replace one from same manufacturer that is still serving me well but wanted to try a little more power, new amp 1.4 watts versus a .35 watt on the older one. Have about 25 hours on new amp and turned it on this morn loaded CD and after about a minute the music was replaced with an elevated fuzzy noise right before fuse blew, replaced fuse and it blew a second or two after turning unit on, saw nothing unusual going on with the tube glow, replaced New amp with the older amp in system and all is well. What are the possibilities of fault here, would like to handle myself without having to send back to Japan for warranty work.
tooblue
atmasphere's avatar
atmasphere
11,862 posts
 
Raindances is one of their better albums.

@tooblue , what happens if you replace the power tubes? Does it still blow the fuse?
tooblue OP
1,934 posts
 
Do not have extra tubes, it uses an obscure C3M Siemens. When the fuse blew initially I was listening and the music was replaced by an elevated hissing distortion for about a second before fuse blew and didn't see any tube glow anomalies.
tooblue OP
1,934 posts
 
Never heard of the band Camel but just googled them, don't know how they got by me being a product of the mid 60s.
atmasphere's avatar
atmasphere
11,862 posts
 
The tube glowing oddly does not happen all the time.

Remove the power tube and run the unit. Does the fuse blow? If yes => it needs service, probably in the power supply. If no => install the tube and try it again. If you hear odd sounds, tap on the tubes and see if any respond. The socket might be loose (but that usually won't blow a fuse unless its the grid connection on the power tube that is loose) which can make crackling and popping sounds. So you have to sort out which is which. Sounds like it would be a good idea to obtain a spare power tube regardless since they are not all that common.
tooblue OP
1,934 posts
 
atmosphere, thanks for your input, currently out of fuses but did just order some off ebay (damn I miss Radio Shack) and some back up tubes. when the fuses arrive I will remove the two c3m tubes and give it a try and see what happens. Going to try that before taking it to a tech for diagnoses. Unit is brand new and did work well with no issues for at least 20 hours, the first 16 being burn in hours and the last 4 actually listening.
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