I was just listening to Ayreon's new CD, 01011001, and I found that it has a TON of low frequency stuff in it. It's progressive rock style with some synth added.
The whole album is badass and full of nice baselines and the music is excellent. It's for the progressive rock/metal fans but here is a sample to hear what the music is like:
http://files.filefront.com/tracks1+4zipzip/;9802206;/fileinfo.html
I will give you a warning in that the song "Unnatural Selection" has a chorus that has a bass line at 15hz and 30hz at pretty high levels so make sure you have some sort of subsonic protection if it is needed. I think that or the other song only go as low as 27hz so not much to worry about there.