Generally speaking anything below 60 - 80 hz is pretty difficult to locate. 150 hz may be easier to locate than that, but not a whole lot easier. I guess if you found it was too easy to locate, you could always cross it over lower. It's the 60 - 80 hz boost that you're really after with one of these units anyway, right?

My Stuff :

M80's
QS8's
VP150
EP800
Denon 4802
Emotiva XPA-3
Samsung BD-P3600
Sharp 65 Inch Aquos LCD