Depending on how you have it connected, it can be done. You can just split the audio signal. If you currently have it connected via optical, you can split the output from the source to connect it to both soundbars. I have never tried this but it should work. Any chance that you could just move this soundbar to another room and get one of the newer Vizio or Phillips soundbars with rear speakers?
If I was going to connect 2 soundbars, I would just get a decent 5.1 system instead.
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