As I have indicated several times before, a subwoofer is an excellent
addition to the Vanagon. The possible loss of space in the Westfalia and the
need to place where it would be most effective put me through several
iterations. My current solution has been pumping away for years.

In my case, I start with the diesel vanagon and the two undefiled
compartments beneath the driver and passenger seats. After due consideration,
I designed a sealed enclosure tuned box for a 10 inch sub. I used a Pioneer
(details in the archives) with Thiel parameters consistent with the space
available under the driver's seat. Of course I built an enclosure with medium
density particleboard and used it to "line" the full available interior of
the compartment. I mounted the subwoofer in the center of the rotary
retaining plate that supports the swivel seats. The gap between the bottom of
the seat and the top of the protective grill on the subwoofer is about 1 cm.
I filled the enclosure with fiberfill. I adjusted the amount of fiberfill to
make the measured transfer function exactly match the optimal response of the
sub, my crossover network and the amp. I then mounted a (now) 400 watt rms
amplifier to drive the sub on the Westfalia cabinet wall face behind the
driver's seat back. I also mounted a CD changer there for easy access from
the rear for musical set changes. The underside area under the passenger seat
holds the monster 4 channel amp for the rest of the system. Circulation fans
with thermostats mounted in the metal face below the seat. Didn't infringe on
the battery box area. Instead, I put in a hard rubber battery box (cut to
size) to contain tools and other goodies. I believe the pictures are on
Alistair Bell's web site. So much better than the Bazooka (10) or the dual
truck boxes. Easily gets the attention of an 18 wheeler when I pass, windows
up, with the Ride of the Valkeries pumping at a level I enjoy. Helps justify
the front to back 00 gauge rewiring and the caps behind the glovebox.

Frank Grunthaner