Issue with Ampeg BA210V2 Bass combo

ellangus

My son bought a used BA210V2 from somebody yesterday in a private sale.

We tested it at the sellers home and all worked fine.

He took it to rehearsal later that evening and used it for around half an hour - all good.

He switched the amp off for a short period and when he switched back on there was no sound at all, the light came on but no sound.

He switched it off again left it for a few minutes switched back on and it was working again.

He brought it back home and so far we have found that the problem continues, we left it on for an hour with no problem.

We then switched it off - no sound again, switched off - left it for 5 minutes - switched back on - working again.

After lots of switching on an off we found that if we leave it on for say 5 mins or so, when switched off and then back on we get no sound unless we leave it off for say another 3 mins or so, then it works ok when switched back on. 

He loves the sound of the amp (when working) and would like to keep it if we can get it sorted.

Any suggestions would be most helpful.

ICBM

It could be something to do with the thermal protection switch (I'm pretty sure it will have one), or if it has a relay-operated mute circuit (I'm not sure about that model) - but the most obvious thing to do is stop turning it off... there's no need, and if anything it's generally better for electronics to remain on rather than going through on/off temperature cycles.

It may be worth asking on one of the bass forums if anyone else has found the same fault, and if they had it fixed what the cause was.

ellangus

Thanks @ICBM That's what we were thinking.

I have posted the same thread on Basschat.
I've also sent a message to Ampeg.

ellangus

Spoke to Surrey Amps who do all the non-warranty repairs for the Ampeg distributors in the UK.

The chap I spoke to in the workshop asked how old the amp was - I told him I wasn't sure but when I described the issue, he said it's probably around 4 years old and was aware of the problem. He said it was in the power amp and that they could replace the part but there are a number (didn't say how many) of this part and that it would be prudent to replace all of them at a cost of £125 - £135 + VAT along with the cost of collection and delivery (£35 +VAT).

Obviously a known issue in Ampeg amps!! I wish manufacturers would stand by their products.

ICBM

That sounds like a lot of money to fix something that doesn't show up unless you turn it off and back on again. In fact it sounds like quite a lot of money to change a few parts in a solid-state amp...

Did he say specifically what type of part it was?

ellangus

He just said it was components in the power amp? 
It was obviously aware of the issue though, as soon as I described what was happening he pretty much diagnosed it on the phone. 
I've since spoken to the seller who has offered to take the amp back for a refund or pay (up to £50) for repairs if we'd prefer to keep it.

I've also spoken to a local amp tech (Dave Lunt) who said he'd charge £30 to diagnose it (which would come off the price of fixing it if we went ahead).
He reckons it would be cheaper than Surrey Amps quoted.

ICBM

I would probably give Dave Lunt a try. I don't know him but that sounds a reasonable charge for diagnosing an unknown (to him) problem - the seller's offer more than covers that part of it anyway. Unless you just want to give up on it, in which case take the refund.

ellangus

Decided to get the refund.  Got a Mark Bass 500 tube head instead and looking for a Mark Bass traveler 102P cab to go with it.