TV/VCR/Stereo Troubleshooting/Home theatre issue


I have denon av 1312 pairing jbl SCS 140 speakers and woofer..problem arise from last few days is that my sub woofer is working but it has lost its performance upto 70%...
I have checked all the connections but unable to solve the problem.
Pls help

I'm not certain what you mean by lost performance.

My first guess is the voice coil of the woofer cone has developed a shorted turn or more. Listen to the woofer up close at a low level. If you hear a scraping or rattling noise then you have a bad voice coil in the sub.

They can often be repaired by a speaker repair shop - which are found in bigger cities.  Or you could buy a replacement woofer driver. You might even find one on eBay.

Let me know more if there is more to the story.  

TV/VCR/Stereo Troubleshooting

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