Velodyne Subwoofer HGS 15, not SVS, Rel acoustic, JL Audio

this subwoofer is being produced catering Music and Movie applications with the servo technology and Acoustic suspension Concept.
despite the age of this unit, it is still one of the best out there comparing to JL audio F series, or Flagship sub from SVS

A very rare subwoofer of its kind. Listening is believing with its servo technology and very stiff cone with very large voice coil.

See world wide review for its five thumbs up performance .

There is a big difference between a good subwoofer and a great subwoofer. Good subwoofers can play low and loud. Great subwoofers can play low, loud and still maintain a high level of accuracy The Velodyne HGS-15 is a great subwoofer. Its placement flexibility and stellar performance with both two-channel and multi-channel make it an easy recommendation. The fact that it is entirely built here in the USA is icing on the cake.