subs
#4
I believe they are well known as SPL subs that are specifically for the purpose of "burping", or giving a huge peak in SPL in a very small frequency bandwidth. They have and may still hold many records in dB drag type contests. I'm not into that myself, but I have heard of them for several years. They may now have some other lines that offer SQ possibilities, but I doubt it. They know where the money is.
#6
theres not much more i can say, but u gotta hear them for your self.. heres the website for more information. www.ddaudio.com