I have the 500 and it is carthilage crushing. It depends a lot on how many seats you need to have perfect bass. If it is just a few that are closely located, one 600 will probably do exactly what you want (I wish I could have physically had one in my appartment). If you have many seats, you COULD need 2 or 4 subs to homogenize the bass fields, but there is not garentee that you will.

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