JVM Forum

Hi all. I have been gettiing ready to join a new band so I upgraded my rig to include a JVM 410H. I have been using it off and on at home since buying it before xmas. All was well until last night when I heard a fairly loud click after powering it up and now no sound at all. I have checked the fuses and they are ok. There does seem to be some glow from the valves and the main channel lights are all working. Does this sound like a dodgy power valve? I do not get any sound either from silent running the preamp out via DI on back of amp.

I guess this means a long trip back to the dealer for a repair under warranty?

Regards

Steve

If the DI out doesn't work it's not down to the power valves.

You can test that tho by using the JVM as a slave from another amp (serial loop in).

Even though it seems obvious, check your guitar cable, the guitar, speaker lead, speaker
and make sure you didn't engage the effects loop with nothing in the loop.

If no joy, get hold of a preamp valve and check this thread out as to what does what.
I'd start at V1.

http://jvmforum.com/phpBB3/viewtopic.php?f=7&t=1109

There are some internal fuses on the circuit boards also, check those out.

I had a very similar problem - the symptoms all sound the same and the amp had only been used at home during down time in rehearsing/gigging. It was barely 2 months old, so was repaired under warranty.


It turned out to be "missing screws, and a broken wire" according to the repair docket. No more detail, but it works now. I love this amp, but found this to be infuriating.

How long a trip back to the dealer are you talking? Always better in my opinion to make them do the fault finding hehe :p

Sounds like a similar thing to what i had, turned it on and it went pop, and hardly any volume would come out, very farty and poppy and crappy. - was a small tube and some stuff on the circuit board i think.