Peavey 2600 amps

[paulears]

I've had a couple oif amps in a rack for a few years now - Peavey 2600s, and they've been pretty good, coping fine with open circuits and a few shorts, but 4 months ago one suddenly became really load sensitive, with the feature of muting the output, but only after a second or two - at any level. I replaced it with a Thoman 2400, which was to hand and all was well. However, yesterday after doing a job where it performed fine, after being driven back and re-rigged in another venue, this one developed the same fault - which considering the previously solid service seems too much of a coincidence?

[gyro_gearloose]

Are both amps being used with the same signal source, leads, and speakers? Getting the same fault on two different amps would suggest that something other than the amps are at fault.

[DrV]

Are both amps being used with the same signal source, leads, and speakers? Getting the same fault on two different amps would suggest that something other than the amps are at fault.

 

+1 to the above but also, are the amps now permanently faulty or is it just when they are on this rig? I'm not familiar with the Thoman 2400 but is it a rebranded Peavey?

 

Regarding a fault which would make the amp 'load sensitive' , the 2600 uses 4 transistors per side in parallel. If one or two of these, or their associated emitter, resistors had gone open circuit then the amp would probably work successfully into a high impedance but would go unbalanced into a low/normal impedance load, tripping the speaker protection. I haven't got a picture of the innards of a 2600 but one very likely problem which could be caused by rigging/derigging/driving along a cart track (!) is that the resistor leads get fractured. Especially if they are large rectangular ceramics, mounted off the board with no mechanical support.

 

Worth a look?

 

Dave

[KevinE]

Do you mean the 2nd of 2 Peaveys developed a fault, or the newly installed T-Amp?

[paulears]

The second Peavey - there are quite a lot of the large ceramics on quite long legs, I'll pull the faulty one apart and check these. The first failed in situ - so had no harsh treatment at all, a semi-permanent install, but the second was indeed taken across a field, so it could be a mechanically induced fault. The Thomann amps are a similar design, but Chinese sourced, and I've got ten or so of them doing various things and touch wood, they've been very good. The feeders for the first one haven't been moved since the install - and the replacement amp just took over with no issues. It just seems a little odd to have the same type of fault on the only two of these models I have. They've given great service, so don't owe me anything.