ID max is on the top of my list. JL w6v2,eclipse TI,Alpine type X,RExxx,Adire Brahma,OZ matrix Elite's, there are more but those are the top few that come to mind.
Some that people don't talk about as much are the Dynaudio MW190s, they're not SPL oriented in any way, but are extremely accurate subs. Image Dynamics makes great subs, both the IDQs and ID Max are excellent. Eclipse Titaniums are great, Adire Audio Brahmas are excellent, JL Audio W6v2s and W7s are very good. Like James said, the Oz Audio Matrix sub is very good as well.
yeah that OZ sub is very acurate. When I heard it I almost compared it to the old A/D/S 10's from about 10 years ago. Man those were the sub to have back then for ultimate SQ too bad they went down the tubes with Directed.
Velodyne made a car audio sub that was servo controlled a while back. Was fantastic, people didn't bite on it though, I guess it didn't have enough distortion for them . The Oz subs are very, very good, I heard about one guy that was experimenting with it for a 2 way setup with horns, said that sub played up to 1khz beautifully.
yeah I actually heard the same thing that they are capable of playing very high with great quality. I remember the Velodyne subs I wanted to try one so bad but by the time I got around to it they were gone. I heard great things about them when they first came out but they were kinda expensive at the time.
. The Oz subs are very, very good, I heard about one guy that was experimenting with it for a 2 way setup with horns, said that sub played up to 1khz beautifully.