Anone else have this problem before?

[Sling Blade]

My 550 Express is my first TUBE amp.

Since I bought it I have been having problems with it cutting out. The volume drops to a mere whisper. Sometimes after a hour of playing or sometimes it does it when I first turn it on for the the day.

I have taken it to the Mesa dealership twice to have it looked at. They reported that the amp checked out fine and that it was most likely my power source.

Today I used a meter to check my power from my outlets. Now it should be reading 110 or above. This evening my power is reading between 105 to 108 and I have seen it drop to 104. And wouldn't you know it my amp is not working.

I have been told that a power conditioner will solve this problem. Is this true? If so is there one out there that won't cost me a ton of cash? If this is in deed the problem.

 

[clutch71]

Have you had any other problems with electronics in the house?

Have you contacted AEP to determine if there is a fault in the house somewhere?

You could (and I'm no electrician) have a problem with a ground fault in the house. I had one that was bad that would trip if I plugged to many items on the circuit. Ran from the basement to the garage to the upstairs. Real PITA. I replaced the ground fault outlet upstairs and it seemed to have corrected the problem.

Best of luck.

 

[Sling Blade]

Hey someone does care! LOL!

I am taking my 550 back to Mesa today to get fixed hopefully. Last night and this morning when I tried the Express it would not work. Same thing, just a mere whisper. I checked the power with my meter and the outlet was fine. 123v. I never thought about it before but a friend of mine gave me a 1985 Peavy Bravo 112. It runs on EL84's. I plugged that in and it worked fine and sounded great. While the Express sat over there and just mumbled. I think that rules out any power issues.

Though I must say my first experience with Mesa products is turning into a sour one. It is sad when I can turn on a 1985 Peavy (probley never even retubed) and it works fine but my new Mesa tanks.

Peavy bravo selling for $300 (works)
Express 550 selling for $1200 (Doesn't) UURRGH!

 

[nemesys]

Intermittent low voltage like that can cause damage to a tube amp. It'll usually show up in the OT, if I remember correctly, the voltage change causes it to need a different speaker impedance. After you get the amp back, a power conditioner may be a good investment -- you can get a good one for less than $100.

I hope everything works out okay with it!

 

[Chris F]

The pursue of tone can be a winded and occasional painful road 8) Don;t let that bug you, hopefully the repair/next one will be fine. I've had expensive amps create agony for me before (not mesa).

Hope everything works out.

Chris

 

[ursinus]

I do some amp work for a local boutique shop and they get amps from England that cost 3200.00-3900.00 (the name shal remain nameless) and have had to repir about 50% of what comes in. Bad switching relays, cold solder joints, bad footswitches, backward wiring in the footswitches, blown high voltage power resistors. So it happens to pretty much all manufacturers. Give Mesa a chance to make things right. After 20+ years of being a Mesa user, they have never let me down.

 

[cottoneyedjoe]

Same problem with the 5:25 and my Studio 22.

Here is what you do. It is your effects loop. Take a short patch cable and patch the effects send and return together. It will never cut out again. Unless it is another issue.

There is a review of the 5:25 in the new Guitarist magazine. They had the same issue. It is due to how the effects loop is wired in most Boogie amps.

Talked with Rich at Mesa yesterday and he also agreed it is a normal occurance with these amps.

If you don't want to do the patch cable thing, then clean the contact points in the effects loop. You could also take it to a tech (Mesa Authorized to not void your warranty) and he could replace the jack.

That is what your problem is though. I am 98-99% sure of it.

I really don't think it is the voltage in your house. Even if you are running at 105 volts you should still see power to the amp. The sound may be weaker, but you will still see power. You will not have a volume cutout like you speak of...

Trust me on this. Try the effects loop.
My buddy has had the same issue with his as well.

 

[Sling Blade]

Same problem with the 5:25 and my Studio 22.

Here is what you do. It is your effects loop. Take a short patch cable and patch the effects send and return together. It will never cut out again. Unless it is another issue.

There is a review of the 5:25 in the new Guitarist magazine. They had the same issue. It is due to how the effects loop is wired in most Boogie amps.

Talked with Rich at Mesa yesterday and he also agreed it is a normal occurance with these amps.

If you don't want to do the patch cable thing, then clean the contact points in the effects loop. You could also take it to a tech (Mesa Authorized to not void your warranty) and he could replace the jack.

That is what your problem is though. I am 98-99% sure of it.

I really don't think it is the voltage in your house. Even if you are running at 105 volts you should still see power to the amp. The sound may be weaker, but you will still see power. You will not have a volume cutout like you speak of...

Trust me on this. Try the effects loop.
My buddy has had the same issue with his as well.

You were absolutley correct! As soon as plugged in the patch cable I heard the amp kick back to life! Thank you so much! Know I wonder why my Mesa dealership didn't know about this?

Thanks again. That's is why I love this forum. You guys are the best.

 

[lyman]

i just found this thread. good call, cottoneyedjoe. i had the same problem with my maverick a while back. i spoke with a tech around where i live and he suggested the patch chord in the loop method. cleaning the jacks or even just working the plug in and out of the loop might help. unless you physically are making the connection, the jacks tend to drift out of spec. mine has been fine since. good luck!

 

[Jak0lantern01]

AN AMP DROPPING OUT AND BEING FIXED IS NOT "A NORMAL OCCURANCE", IT IS A DESIGN DEFECT!!!!!! Sorry for the caps, but if it is the way the amp has been designed, it is an issue that Mesa should be addressing. Don't get me wrong, the Marshall's are trying to seduce me these days, but I refuse to dump the Boogie. I'd hate to hear, though, that Mesa is talking about a defect as a normal thing.

 

[cottoneyedjoe]

It is because Mesa designs there amp with a serial effects loop that is an active part of the circuit.

Sometimes those contacts become bent, sometimes they get dirty. Contacts that get dirty are NOT design defects but normal wear and tear.
Now designing the effects loop as an active part of the circuit is Mesa's design. However, if you take the effects loop out of the circuit it is a seperate circuit board and more problems you may have to deal with later.

Think of it like a car with auto locks and windows. One more thing that could break.

It is not just Mesa that does this either. I have a Rivera that has had the same issue before. The only real way to stop it is to buy an amp without an effects loop.

 

[lyman]

the pumkinhead has a good point. i'm a little surprised that was their response, unless they or the poster was using "normal" and "frequent" interchangeably.

 

[Barry]

You dont want a power conditioner , You want a voltage regulator . Furman makes some nice ones .