Help with switches on JBL Pro 2.1 speaker system

[Bombay]

I have a JBL PRO PREMIUM COMPUTER SPEAKER SYSTEM that I am trying to repair. It consists of two satellite speakers and a powered subwoofer.

The on/off and volume controls consists of two momentary switches on a board. To turn the speakers on, you press both buttons simultaneously. To turn the satellite speakers up, you press the right button...to turn them down, the left button.

The system still powers on, but I can no longer control the volume through the switches. I am making a guess that the switches are bad (they do crackle).

Here is a pic of the system that I found on ebay. On this auction you can also see some of the electronic specs.

The only voltage specs that I can find are on the back of the subwoofer.
AC 120V~/60Hz/175W

I found some momentary switches at radio shack that are identical in terms of form factor, but the switches are rated at 50mA @ 12V DC. Here is a link.

Would these work or do I need switches rated at 120V AC?

Let me know if you have any questions that I can answer that would enable you to better help me.

thank you
Rob

 

[Resqueline]

If you can power on the system with those switches then obviously both of them works. Are you saying you can hear the actual switches themselves crackle?
Those switches are controlling an audio "processor" in the sub and are certainly not connected to the mains.. You'll have to look further into the system to find the fault.

 

[Bombay]

If you can power on the system with those switches then obviously both of them works. Are you saying you can hear the actual switches themselves crackle?
Those switches are controlling an audio "processor" in the sub and are certainly not connected to the mains.. You'll have to look further into the system to find the fault.

Hi Resqueline:

Thank you for your reply and insight. When I press on either of the switches to turn the volume up/down, a crackle sound comes from the speakers. It appears to be related to pressing the switches. I see your point...if the switches turn the unit on, then they can't be entirely dead. I suppose for the most part that switches either work or not.

I guess I will have to look further into the subwoofer to find the issue. There are no burned components, so I am not sure what else to look for. Any thoughts? What does the "audio processor" look like and what does it do?

Rob

 

[Resqueline]

Yes, the switches only provides some logic level inputs to the "audio processor" (whatever it is, I don't know) so if the audio crackles then the processor has failed.
What's your skills and tools? The first thing to do is to try to locate a schematic diagram of the sub. The next is to measure if the power supply is ok.
Of course it may all end up with trying to get hold of a possibly unobtainable replacement "audio processor". It's not easy to diagnose the "audio processor" btw..
(It takes the button logic levels and counts internally and adjusts the volume up & down, plus it might be doing the sub-filtering.)

 

[4businessh]

JBL Pro Premium Speakers

Bombay,
I have the exact same speakers and the exact same problem with them. Have you found any solutions to your problem. I too thought it must be the switch and due to someone having had water/moisture on their hands when they pressed them.
Any solution would be appreciated.
Thank you,
4businessh