SWR 2x10 Combo problem

bmohara · #1 04-09-2010, 08:52 AM

My SWR 2X10 Workingman's Combo starts to break up after 1 to 1.5 hours of use. Doesn't happen if it's just turned on and left for a couple of hours - seems to be the load/heat of playing through it. Happens consistently.

I tried it with several basses (active and not) and cords and once it starts to distort they all sound the same. There are no pedals involved.

Took it into the local shop here in Toronto, described the problem and they tested the heck out of it and say they couldn't find anything wrong.

I really like the amp but now I feel stuck.

Any ideas ?

Brian

rumblethump · #2 04-09-2010, 12:10 PM

Buy a small clip on fan and point it at the rear of the amp. It sounds like its overheating under load. I ran into the same problem with my SWR Workingman 300 when I ran it a 2.67 ohms even though it's rated to handle this load.

Walking · #3 04-09-2010, 12:15 PM

I assume you already took it apart and blew the dust out of it and ensured the heat sinks and fan blades were clean--or the techs did, but might want to check...

Might want to get the part number off the fan and look for a new one--or maybe a more powerful ( cubic feet per minute of air) one of the same size. Its kind of guessing, but I will guess and do a cheap fix to see if it works.

Also, inspect the electrolytic caps for swelling or discharge. It may be in a borderline state of operation and then fails when heated up.

bmohara · #4 04-09-2010, 12:26 PM

Thanks for the responses guys

I just got back from going to pick it up even though they had not been able to fix it ... the guy there who was not the guy who had tested it decided to give it one last try to see if he could re-create the problem ... plugged in a a Fender jazz Bass and played pretty aggressively for a couple of minutes - no problems - then just as he was about to give up he hammered away on a low G and there was a bit of crackle then more then the problem reared its ugly head in full bloom - thank god - so it would seem to be related to some sort of resonant vibration and a loose something inside that perhaps becomes more susceptible the warmer it gets - anyway, they took it back into the shop and said to come back in a couple of days and they should have it sorted out.

I just wasn't experienced enough to look for a specific frequency to cause the problem.

Thanks again for the responses guys.... I'll follow up when they have it fixed to say what they found so others can benefit from my experience.

Brian