Active Speaker repair – W-Audio PSR-8A

Active speaker repair powered speaker repair W-Audio PSR-8A

I just came across my notes for an active speaker repair on a W-Audio PSR-8A monitor. It’s an affordable W-Audio PSR-8A that was being used in monitor duties by a Grantham based keyboard player. The job was competed last year, but I thought I’d blog about it now.

The mains transformer had died. I replaced this with a new 160VA unit, sourced from RS. The new transformer was larger than the outgoing unit, so a small amount of plastic had to be removed from the inside of the unit.

If you have an active speaker repair, please get in touch.

Ashdown 550 Touring Repair

Ashdown 550 Touring Repair

The first task for last week was an Ashdown 550 Touring Repair, brought in from a Newark customer bec because the amp wasn’t making any sound – actually it was making a very weak tinny sound. I like ‘no output’ or low output repairs – they’re often easy to fix. Fortunately this was the case here.

The problem turned out to be a faulty speaker connection. The touring 550 has two 10″ LF drivers and a little HF driver. There was a loose connection in one of the LF drivers – I suspect from the way that wire broke that it had been badly wired in the factory. The weak, tinny sound was the tweeter operating on its own. I re-soldered this connection and added some heatshrink to support the connection. And the amp was working!
Ashdown 550 Touring Repair
It was obvious from the external state of the amp that it had been kept in a damp environment – the tolex and top wood layers had swollen around the screw joints and the fixings were horribly rusted. The owner had bought this amp in the faulty state, so I then proceeded to give the amp a 1 hour service to check for any further sonic gremlins.

The amp uses two preamp valves – 12AX7s. These were unbranded valves but tested fine on my valve tester.

I discovered that the master volume pot was quite badly oxidised, but cleaned up nicely with a bit of Caig DeOxit D5. The gain pot had similar problems. I also cleaned the sockets and the valve bases as a precaution.

Checking the output level into 6.8 ohms the amp produced >288W. This is about right for a 550W amp rated into 4 ohms, which would produce a proportionately larger signal, allowing for transformer sag.
 Ashdown 550 Touring Repair
If you have an Ashdown 550 Touring Repair, please get in touch.

PA speaker repair – dB Arena 10

pa speaker repair

Last year I completed a PA speaker repair, I’ve just found the photos of the damaged crossover so I thought I’d blog the repair.

The owner had bought a pair of these nice dB Arena 10 speakers from a disreputable eBay seller. One was working, but the other had a fried HF compression driver and a damaged crossover.

Fortunately the 1 inch dB compression drivers are commonly available from the likes of Thomann so this was easily replaced.

A resistor had also burnt out in the crossover so I replaced this with a higher spec part.

Upon completion I graphed the frequency response of the crossover and compared it with a known good unit.db arena repair

If you have a Pa speaker repair, please get in touch.