The forum on the HSU website discusses a new series subwoofers (VTF series) coming out in the next few months. A quote from a HSU employee on the site about the high-end model:

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Here are some specs:

-12 inch woofer
-22 Hz extension
-Single Tuning
-Output at least equal to the Outlaw's
-around $550 in price

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Interesting, no?