Jim does not add the customary underdamped bass hump, so Thiel bass is honest.
Teeheehee. I think I know which brand you're referring to ;^)
Soundstage's loudspeaker measurements are done in a true anechoic chamber and, therefore, do not suffer the compromises of quasi-anechoic measurements done by Stereophile. Anyhow, if you look at their measurement library, the CS2.4 is down 6dB, relative the level at 1K, at ~31 cycles. This compares very favorably to other much more costly designs such as the Wilson W/P 8 (~38) and KEF Blade2 (~31). Nevertheless, some of the other designs with slower roll off can benefit from boundary reinforcement to increase low bass in an actual room.
When I got the CS2.4s, the first thing I noticed was improved bass definition relative to the otherwise well-accomplished Vandersteen 2Ce. I listened to many tracks before noticing the 2.4s don't go quite as low (specifically, a Tracy Chapman song with organ tones).