View Full Version : L212 Subwoofer problem

11-21-2006, 08:02 AM
I got a pair of JBL L212 in which the powercompany unfortunally have blown the amplifier in the subwoofer. Everything works, but the 50Hz tone (i am living in Sweden) from the main voltage is getting through to the woofer. I think the capacitors are blown and wonder if anyone has any ideas of where i can get new ones. I have searched the net but could'nt find anything. It would be nice to use the speakers with original amplifier for the subwoofer.

11-21-2006, 08:24 AM
Here's the Service Manual if you need it.

L212 Service Manual (http://manuals.harman.com/JBL/HOM/Service%20Manual/L212%20sm.pdf)

Right-click, Save Target As...

11-21-2006, 06:54 PM
Here's the Service Manual if you need it.

L212 Service Manual (http://manuals.harman.com/JBL/HOM/Service%20Manual/L212%20sm.pdf)

Right-click, Save Target As...

Hi Giskard

The link comes up as page not found ?

You wouldn't happen to have access to the service manual for the ESC200 surround processor/amplifier by any chance.:bouncy:
I'am currently trying to repair one bought off e-bay, all 6 speakers arrived in great shape but the amp has a blown component in the output stage & there is unfortunately nothing more that i can do without a schematic, have put pictures in my last post which i cant seem to attach here ?
Any information would be greatly appreciated.

Cheers Wayne.

11-21-2006, 07:09 PM
The link works in CA.

[Title page is kinda tilted, tho.... ;) ]

11-21-2006, 09:44 PM
YOu may have shorted a Diode as well, causing AC to get through. Don't turn it on until you get it fixed, there may be AC present on the parts that could be hazardous.

11-22-2006, 04:09 AM
Thanks for the service manual.
I will check the diods too, it would be easyer if it 's a diod that is causing the problem.
Thanks for the tips.

Reinhard Schulz
04-07-2007, 08:57 PM
Quite some time has passed since the thread was opened. Nevertheless, if somebody else faces a similar problem with his L212 Ultrabass Energizer I thought that I post my experience here.

I had by a sudden similar symptoms, strong 50 Hz hum and 1.2 V DC on the output.

Turned out that the bridge rectifier was blown and AC passed into the amplifier. Fortunately I realized it immediately and shut the unit off. After replacing the rectifier with a new Si-Type (4A current capable) the unit worked fine again.

04-07-2007, 10:52 PM
I had a different problem with my 212's bass amp. About 2 watts output only. The repair was simple and cheap. 2 faulty capacitors about 3/4" long (C8 and 7) restored the amp to as good as new.