@Jafant, am confident that I am not alone in thinking that there are instances where the CS 2.7 and/or the CS 3.7 would require subwoofers.
Utilizing a proper power amp will not unto itself act as an equalizer to yield aural results across the frequency spectrum beyond the scope of a loudspeakers limitations.
There was a reason that Jim Thiel made other models besides the 2 and later 3 series that had a broader aural frequency spectrum range, as well as a range of subwoofers to facilitate a broader aural frequency range.