http://www.nakusa.com/master/sps5200_spec.htm
or
A/D/S
the only other speaker I have heard that I like is the alpine spx and they wont fit in my car's doors.. too deep. 2.88 or so I think. I already have a nak head and I have always loved the tight sound from the nak subs. But, I hear a/d/s...