I have two JL Audio 10" WO subs mounted in a down firing Probox ( http://www.proboxrocks.com/products/...DF/index.shtml ) for a 99-06 ext. cab GMC or Chevrolet Full size truck.
I also have a JL250/1 Mono amp to push these subs. This setup gives a nice clean, clear, crisp sound and works...