Here's what Peter Marcks (HSU Rep) said in explaining what the turbo charger is, and what it does.

In reply to:

The 'turbocharger' is essentially a port extension that attaches to the rear port(s) on the VTF (or STF-3) subwoofer, extends outward and upward in a U-shaped fashion, and then fires forward on top of the existing subwoofer. The 'turbocharger' ports are housed in a box no more than ten inches high and no more than half the depth of the subwoofer, and the unit should be easily removeable if desired when not in use.

By extending the port length, the 'turbocharger' allows us to effectively lower the tuning point of the subwoofer without reducing available port flow area (as is the case with existing variable tuning solutions, where port flow area is reduced by 33-50% with each lower tuning point), and without compromising floorspace.

There is more to the story than meets the eye with respect to the upgrade option for MK2 owners, but I need to keep quiet about that for now!





Sutter