Mesa Dual Roadster Continued Problems- intermittent shutting

I'm nearly done with this amp, it has been checked over by the local mesa dealer who cannot figure out anything wrong (or will not spend the time to really test it out). It has been turned off for nearly 3 weeks and just now I had it going at 3/10 volume for about 10 mins and all of a sudden it just shut off completely, all lights, everything completely off. And in the time it took me to pull up the forum and write this post all the lights are back on and the amp is running again. About 2 months ago, same thing, just randomly shut off, then randomly fire back up. He checked out all the tubes, and the amp has 4 years warranty left, but I've had gremlins with it big time.

Any thoughts?

About all I can suggest is verifying the power cable is serviceable. Beyond that, I'd call Mesa. They seem to have this talent for leaning on a dealer and making them show more interest in diagnosing a problem.

A faulty power switch could do exactly that.

Would about have to be a switch or connection issue. If nothing else just pull the chassis and send it to Mesa's home shop. Hassle+cost, but surely they'd fix it right.

Certain wall outlets can cause this, if they are, or have a ground fault circuit interrupter outlet between the outlet in use and the breaker box in the dwelling. When it does it, verify there is still power from the outlet.

You haven't said if this only happens at home in a certain power outlet or outside of home and everywhere else.

If it's only at home through one particular power outlet that you're plugged into all the time, then at the service centre it's probably OK. So logic says that the service centre didn't find anything wrong.

You need to clarify if this happens through any power outlet inside the home and outside the home.

In Australia, the maximum Amps through one power outlet is 10 Amps. If you have heaps of stuff connected, the fuse will trip, or worse, cause a fire. So make sure you haven't got 10 things plugged into one power point, this includes multi outlet boards with 6 things pugged into it connected into one power point.

If it happens regardless what power outlet you're plugged into, call Mesa. You've got four years warranty left. Use it rather than bang your head in frustration. Ask them if you can take it to the service centre and get them to post it for you. Alternatively, ask if they'll replace it. If you don't ask, you'll never know.

Good luck.

I'll bet it's the power cord or wall outlet.

When the amp dies, have you tried wiggling the power cord at the outlet and/or amp?

Try a different power cord, one from another amp or PC that works with no issues.

Also, try a different outlet, as mentioned you need to verify the power at the outlet when the amp cuts out. Plug in a lamp or something with a light into the same outlet.

You say you "had gremlins with it big time". What else is not working correctly?

Dom

Thanks for the discussion here everyone. For background info the amp has never left my house or the outlet it is plugged into through a brand new musician-quality sound bar. The house wiring is 5 years old and the only other thing on that circuit is a Mac computer. I've never had any other electrical issues in the house.

It is a long saga with this amp but basically a guy from eBay ripped me off and sent me a demo instead of a new amp, and when it arrived the tubes and a fuse had to be diagnosed and replaced because nothing worked properly. Then for no reason in December, it seemed to lose all power in the middle of playing, and go into this anorexic sound that sputtered and popped and crackled (I have another thread on this). This was also a problem that self corrected between my house and the guitar shop as I could not recreate it once I got there! (go figure)...so they took a run through everything and said it was all fine.

The one thing I'm thinking may be the case here is that when I took it in in December, they gave me a replacement mesa dual rec amp and somehow they did not give the dual rec roadster chord back, and am thinking that it was swapped. It seemed the same to me, but perhaps its different. The amp tech was pretty clear all tubes were fine. I have never tried to wiggle the power chord or anything, but maybe I will fire it up tonight and start playing around with it to see if it makes any fuss.

Will update here.

Try it without the "musician qualtiy soundbar" whatever that is.

Just because the wiring in the house is five years old, does not mean there's not a loose connection, or improperly wired receptical in the house.

This could be a number of things. One thing that comes to mind is that metal expands when it gets hot. If you have a loose or broken connection or PC Board trace, it can be difficult to spot, and it may make enough contact when the amp is cool, but make poor contact when heated. That would be quite difficult to diagnose. I would consider resoldering all the power supply connections, or possibly all connections, in case it's a cold solder joint. If you're not up for that, send it to Mesa and have them go through it in the factory.

Also, even if the fuse tests OK, replace it. Lots of wonky things can happen with a fuse, and they don;t always blow clean open.

Bummer about the problems. Must be really frustrating.

Coleo said:

Thanks for the discussion here everyone. For background info the amp has never left my house or the outlet it is plugged into through a brand new musician-quality sound bar.

Click to expand...

This statement caught my attention.

As far as I know, a sound bar is a piece of hi-fi speaker cab.

Do you plug the amp into a proper guitar cab? You don't say hence my questioning.

Also, plug the amp into other power outlets with nothing between the power cord and the outlet. And I have to say this (and I certainly don't mean to sound condescending): make sure your amp is plugged into a proper guitar speaker cab with a proper speaker cable (not instrument cable) before switching the amp on.

What we want to do is start a process of elimination.

1. Proper guitar cab with proper ohms?
2. Speaker cable (not instrument cable) connecting amp to guitar cab?
3. Try different power outlets throughout the house.
4. Use a new power cord to the amp.

If all the above are satisfied and the amp still switches in/out, call Mesa and discuss the problem. It's under warranty, so use it.

As mentioned in the other post, it could be heat related (expansion causing a disconnect). Who knows, it may just be a loose nut that needs tightening.

We look for simple diagnosis and quick solutions and sometimes they just don't come through. The PCB has plenty of components and wires. The components themselves can have internal parts (switches, pots, connectors). Anything can go wrong.

I just read what I wrote and should clarify, I meant power bar, not sound bar, sorry about the confusion! (I just recently purchased one so it must have been on my brain). That makes a big difference. The power bar is pretty heavy duty and high quality and I don't suspect this to be a problem.

The house wiring is not high on my suspect list either, the amp is the problem. I've owned 4 amps plugged into this outlet over 4 years, and it all started with the dual rec roadster.

I'm thinking that it is an internal problem given the intermittent nature of this.

1- The speaker cabinet is hooked up to the amp with a proper speaker cable, per the mesa guidelines. It is not a patch cable. The cabinet is a 4x12 1960 Marshall something or other.
2- I could try running the amp only through the wall outlet and the pedal plugs through the power bar. Or another outlet I suppose as there are a few in the room.

I played around with it last night for at least 2 1 hour sessions and not a single issue. I wiggled the power cable around and nothing changed. No lights on or off. I was not playing very loud (bedroom-ish volume), but maybe I should push the amp a little bit and see if I can get it to heat up and make some excitement.

I'm afraid of sending it to California for Mesa, the shipping will kill me there and back, probably $200 each way from Canada.

OK- the amp gremlins caught on camera! There are two videos here and I'm pretty sure it is now obvious what I'm dealing with (no 'sound' bar involved :? )

- Today I switched the amp power cable directly to the wall outlet and only kept the pedals in the POWER bar
-I played very briefly today for about 7-10 minutes at maybe 4/10 or 11 o'clock in the master output position. Amp sounded great!
- I left the amp on stand by for about 5 hours and came home to play for a few minutes. The second I switched the stand by switch to on, the whole thing shut down. I literally ran downstairs to get my phone so I could record it. The first video (excuse recording quality) shows that when I smack the top of the amp head with my hand a couple minutes in, there is an audible click, and the tubes fire back up and the amp turns on. I do this a couple times, and you can see/hear the amp power engaging and disengaging. Right at the end of the video, you can see it cycling on and off as I touch the amp.
- I tried wiggling the power chord but it really had no effect on this as you can see near the end of the video

https://youtu.be/DfWW7bZbfAM

I came to my computer to write up this post....and all of a sudden, the thing fires back to life. You can see all the lights on and all tubes glowing, with me wiggling the power chord and nothing happening the second time.

https://youtu.be/PY-yZCMohvE

Thanks for info and clarifying the setup.

I've seen the videos. Nice and clear. You should contact Mesa and send them the links.

OK, next is to unplug everything from the amp. Just have guitar plugged in and amp to cab. Remove everything from effects loop. Go to bare basics. Also plug amp into a different power point in another room. You never know, it might run all night without issue. Just try it - it costs you nothing. The house wiring may be 5 years old, it doesn't mean nothing is wrong.....

It seems to be a heat related issue but considering you've played for 2x1hr sessions, it's difficult to say that this is the problem.

Have you tried the amp in Bold and Spongy mode and also Recto and Diode mode? You never now.

I'd suspect a poor connection from the transformer up to and including the power switch and standby switch, or at least a connection inbetween. Considering that the power light does not come on at all when it all goes down and just lights up when it's OK it seems to point to a faulty power switch (or the terminals or wires to / from the power switch).

Have you ever taken out the chassis? If not and you feel comfortable, take it out and take a look --> WARNING; Don't go poking around with bare hands and metal objects. The capacitors could (will) be charged and shock you resulting in possible death.

Just do a visual and see if you notice anything suspicious. You might see a wire that's hanging on by a thread, maybe a connector is not clipped in properly.

Here's a few links that show the guts of Roadster or Roadking. It's to show you the basics of the wires going to / from the power switch and standby switch, the power light and transformer. You can see the wires to / from the fuse. It also shows connectors that you can look at.

https://www.google.com.au/?gfe_rd=cr&ei=x6_fvmkunqwn8qepwocgdq&gws_rd=ssl#q=mesa+boogie+amp+switches+on+and+off&start=10

http://i853.photobucket.com/albums/ab91/mansfieldguitars/RoadsterLayoutJPG.jpg

http://www.seymourduncan.com/forum/showthread.php?149536-Build-Qulaity-of-Newer-Mesa-Boogie-Amps

Youtube - go to 3.30 into video. Pause as you go.
https://www.youtube.com/watch?v=ZKutLcVOGXQ


If you can't be hassled with all that, send an email to Mesa with your story explaining your frustration and lack of repair (be respectful rather than sound sh*tty) and also include the youtube links. Ask them to call you. Discuss the possible postage to / from Mesa. I'm sure they'll want to resolve this for you.

I live in Australia and Mesa have contacted me via email within two days (time difference) and they answered every question I had. Even if their reply had taken an extra day, it's top notch service by them.

Who knows, Mesa have probably seen this issue dozens of times and know the fix that can be forwarded to the service technician. It may simply be a faulty switch that is intermittent (but only fails when you use your amp.....)

Don't compare the service centre vs Mesa the company. Sometimes it's chalk and cheese.

There is a loose connection somewhere between the power switch and the power socket (where the cord plugs in). Maybe the fuse holder is not making good contact, or the fuse itself is damaged.

Coleo said:

OK- the amp gremlins caught on camera! There are two videos here and I'm pretty sure it is now obvious what I'm dealing with (no 'sound' bar involved :? )

- Today I switched the amp power cable directly to the wall outlet and only kept the pedals in the POWER bar
-I played very briefly today for about 7-10 minutes at maybe 4/10 or 11 o'clock in the master output position. Amp sounded great!
- I left the amp on stand by for about 5 hours and came home to play for a few minutes. The second I switched the stand by switch to on, the whole thing shut down. I literally ran downstairs to get my phone so I could record it. The first video (excuse recording quality) shows that when I smack the top of the amp head with my hand a couple minutes in, there is an audible click, and the tubes fire back up and the amp turns on. I do this a couple times, and you can see/hear the amp power engaging and disengaging. Right at the end of the video, you can see it cycling on and off as I touch the amp.
- I tried wiggling the power chord but it really had no effect on this as you can see near the end of the video

https://youtu.be/DfWW7bZbfAM

I came to my computer to write up this post....and all of a sudden, the thing fires back to life. You can see all the lights on and all tubes glowing, with me wiggling the power chord and nothing happening the second time.

https://youtu.be/PY-yZCMohvE

Click to expand...

Hey man, how's this going for you? Did you get it sorted out?

Dom

Sorry for the lengthy delay here guys, I was in the US for 9 days for work and am just back this weekend now dealing with music related things. I did talk to mesa the day before I took off and they looked at the video and concluded that there was something in or around the fuse that was likely the culprit. I was on the phone with them and they had me take out the fuse to look for any scars or pitting on the fuse. Sure enough, I took out the fuse and there were 3 marks on the one end that would connect to the amp side of the circuit. He claimed that was my issue, and that the fix was to replace it, or turn it around so that the end with the pitting/marks was in the fuse holder end, since there were more points of contact. I think its probably just better to replace it, so am going to go to a store tomorrow to look for a brand new fuse.

I will post a picture of it here and then replace the fuse with a new one. I will also give it a test run to see if I can make it unhappy again, but he sounded pretty confident that was the problem. The next fix was to send it back to them, which was a non-starter for me. I really hope this fixes the issue! 8)

I finally swapped the fuse out this evening and after about 30 mins of the mellowest playing session, sitting here reading a tab on the PC, not even strumming the thing, it just shut off completely. And about 3 minutes later, it turned back on. After another 5 mins of the amp just being on and me plucking the strings, same thing, just started to make a really quick fuzz noise (less than a second) and shut right down. About 25 seconds later, it started back up. And I just turned it right off this time.

Sorry to hear you're still having some trouble.

OK, do you think replacing the fuse has at least made a difference? I know it hasn't solved the issue but is it behaving differently? Do you think the amp is on for longer before shutting down?

I'd take a good look at the terminals that touch the fuse. Maybe they're pitted or scarred and making poor contact. Maybe the wire/s coming off the terminals could have a poor connection. Take a flash light to check and/or take chassis out.

I'd take the chassis out and take a very good look at any terminals, wires that may be loose, look for poor soldering and look for loose screws/nuts.

I think you're getting there, as frustrating as it may be. A process of elimination is required. It's also a good opportunity to learn some basic trouble shooting.

Have you thought of going back to the service centre and sitting down with them for an hour with amp open and just throwing some suggestions as possible causes? Sometimes thinking outside the square rather than looking for obvious causes can trigger a different approach to solving the issue.

Alternatively, since you have warranty, I think Mesa should, in good faith, have the service centre ship the amp to them at no cost to you.

Let us know your next steps....

You should check all solder connetions and try a new power cable and check the fuse holder as well. There is a simple fix there, it's just intermitant power that is effected by physical force on the power section. I doubt very seriously it's the PT.