JP-2C reliability

sheehanje · Nov 28, 2016

I had my JP-2C cut out at rehearsal. Was an odd cut out - turning it off then back on would give me sound for a second or two then cut out again.

I figured I'd try 60 watt mode - nothing. I think moved the pairs of power tubes and tried it again. It worked, but only for about 10 minutes then cut out again. Maybe a preamp tube?

Anyways, this is the second time this amp has given me problems in a short time. I brought it in once and they replaced V1 and said it was fixed. I replaced V1 before I had brought it in that time (and I tried multiple 12ax7's in it). So I don't know why the shops tube worked when mine didn't. In fact, I went and replaced every preamp tube one by one - and also cycled in 2 new power amp tubes....

So, my amp is down. We had to cut rehearsal short this time. Last time it went out I had to use a loaner amp for a gig... A bit frustrating. I just went and purchased a rather large (1400watt) FRFR powered speaker to use with my Helix as a backup.

In any case, what have peoples experiences been with reliability - especially for the gigging musician? I know it's a tube amp - I know I will have an issue here and there, but only having this thing a few months now has me a bit worried about it's viability for the long term.

Ibanezex718 · Nov 28, 2016

Sorry to hear you're having trouble with yours, as mine has been nothing short of great in every way. I use mine about 4-5 times a week for practice in the studio as well as gigging about twice a month. I've had the amp since the first ones came out earlier this year and have yet (knock on wood) have any sort of problem with it and have been very happy. I know eventually I will need to re-tube but thats just your average wear and tear. I know Mesa has a great warranty on their products, so if you continue to have problems, I would not hesitate to reach out to them, especially if you got something to play as a back up in the meantime.

sheehanje said:
I had my JP-2C cut out at rehearsal. Was an odd cut out - turning it off then back on would give me sound for a second or two then cut out again.

I figured I'd try 60 watt mode - nothing. I think moved the pairs of power tubes and tried it again. It worked, but only for about 10 minutes then cut out again. Maybe a preamp tube?

Anyways, this is the second time this amp has given me problems in a short time. I brought it in once and they replaced V1 and said it was fixed. I replaced V1 before I had brought it in that time (and I tried multiple 12ax7's in it). So I don't know why the shops tube worked when mine didn't. In fact, I went and replaced every preamp tube one by one - and also cycled in 2 new power amp tubes....

So, my amp is down. We had to cut rehearsal short this time. Last time it went out I had to use a loaner amp for a gig... A bit frustrating. I just went and purchased a rather large (1400watt) FRFR powered speaker to use with my Helix as a backup.

In any case, what have peoples experiences been with reliability - especially for the gigging musician? I know it's a tube amp - I know I will have an issue here and there, but only having this thing a few months now has me a bit worried about it's viability for the long term.

Markedman · Nov 28, 2016

I had that problem but it was because it was becoming unplugged! Where the power cord goes in, it's a pain in the butt so I made a small extension so I didn't have to reach up in there all the time. I don't know why they put it up in there because if you have to unplug it like me and you go to band practice or for show which is several times a week it's a pain in the butt.

sheehanje · Nov 29, 2016

Power was staying on - the sound was cutting out.

Contacted tech support, they said try a new tube in V1, V2 and V5. Just trying to find some time to diagnose it, hopefully by this weekend.

I bought a FRFR speaker to use with my Helix instead of buying a backup head - I figure it will work in a pinch. Unfortunately I traded two amps towards the JP-2C so it's left me thin... One thing I want to try once I get the JP-2C working is using cab clone into the FRFR Speaker - I know it won't sound as good as the vertical 2X12 - but may be a great way to get saturated tube sound at bedroom levels.

bandit2013 · Dec 1, 2016

I have yet to experience this type of issue. I have played almost every day through it.
Your issues sounds like mine with the Mark V within the first two months of use. However, the V was blowing power tubes constantly if they were the Mesa branded tubes. Sorry to hear you are having issues. I would send it off to Mesa with the same tubes in it that you are having issues with if you get no resolve otherwise. When it cuts out, are the heaters on, and do the power tubes have the blue hue on the glass. If all of your tubes are good, there may be a cold solder joint in the amp somewhere or a faulty component. Are you using the Midi? that may be related if you are having issues. If so, do you have similar problems when you do not use the Helix? It could be bad connection on one of the cables vs a preamp or power tube.