Thiel Owners

I have also a set off Kef's R900, bass of the CS2.4 is the better one for sure. 

Andy - couple of quick thoughts. 

1) Correct. A primary difference between the model 2 and model 3 is bass quantity and extension. The model 3 has a 10" woofer with longer excursion and larger passive to produce more than 1.75X the bass of the 2.
2) Jim does not add the customary underdamped bass hump, so Thiel bass is honest.

^...Or a treble roll off. Which is why I think the smaller models sometimes can sound a bit tilted up compared to some of the competition. The more full range (and having the room to properly accommodate that can not be over emphasized) Thiel's are less likely (when properly amplified and set up) to sound bright.

Correct - most designers shape the soundscape toward 'easier to handle'. Jim looked for honesty before all else. Most designers roll off the treble to match the bass roll-off. Jim kept the treble extension regardless of the bass extension. The 1.6 with folk music or a sub-woofer is voiced like the 3.6, etc. His approach was toward accurately reproducing the input signal.

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).