Troubleshooting a JBL PSW-1200 (1 Viewer)

[OhJay]

Have a buddy whose JBL PSW-1200 recently quit outputting sound. The light on the back of the sub lights red when plugged in, and there is a thumping noise when the sub is plugged in or unplugged. Otherwise, nothing. He's out of warranty, so we cracked open the box last night. Pulled the speaker out, it's working when plugged into another source, and the removable fuse seems to be intact and good as well. I've downloaded the service manual and owner's manual, but don't have a lot of the fancy equipment to test all the connections. Any advice on where to go from here?

 

[Robert_J]

Driver works - good. Amp powers up - good. Have you connected it to another source to determine it isn't the receiver that is the issue?

 

[John_Bilbrey]

The JBLs are notorious for the amps failing - the PSW and the PB series. When my PB-12 failed, everything still powered up but the amp itself was dead. $99 replacement plate amp (240w, non-boost model) from parts-express.com fixed it. On the plus side, it sounded twice as good as it did with the JBL amp. It required only a bit of enlarging the cutout as well - easy fix. I didn't hook up the LEDs on the front of the sub though.

 

[OhJay]

Yep hooked it up to my receiver which is currently running my sub just fine. Also ran it high and low inputs to make sure it wasn't just the input he was using that was bad.

 

[OhJay]

If the amp were dead would it still thump on power-on/off? I'm more of a car audio guy myself, and haven't worked with home audio a lot, of course my buddy doesn't know anything about either so brought this to me hoping I could she some light on it. I'll check out parts-express, thanks for the heads up.

 

[Robert_J]

I would assume that the amp would not thump if it were blown but John has personal experience with a blown JBL so I would listen to him. A replacement PE amp is a great deal especially when on sale - http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-804

 

[John_Bilbrey]

Did the sub "go crazy" before it stopped working? Many times the sub will start popping real loud, like a machine gun scene in an action movie or something like that. There are lots of reports of that happening - luckily mine happened while we were watching TV, and not during the middle of the night!

The link Robert provided is the exact model that I got. Couldn't be happier!