Let me present my hidden agenda
http://www.stereophile.com/loudspeakerreviews/218/index4.html
http://www.stereophile.com/loudspeakerreviews/216/index6.html
http://www.soundstagemagazine.com/measurements/thiel_cs24/
I was waiting for this, above in these links to measurements you can see the difference between the 2.4, CS6 and the 7.2 which uses a Gen 2 version of the coincident driver. Atleast 10% smoother than gen. 1
I have a personal opinion and I expressed it, but let me state clearly that the CS6 fans have every right to their opinion about the sound. Funny thing is they have honed in on certain aspects of the sound that makes the CS6 unique to the 2.4. When looking at the maesurements the only thing i would argue is the CS6 having a better midrange, because if we just look at the data that would be hard to substantiate. But it may be their preference. What I'm trying to show is that people have preferences and satisfying those preferences is all anyone needs to worry about but when you're giving advice in a forum its not good enough to simply say its better...better why? How....how can you justify an 8dB dip in the midrange as superior? See a few paragraphs down for why and how.
So as the victim ( I mean original poster) how do you know which way to go? Measurements help guide the way if you can quantify them into what you like and be honest with yourself if something you like does not fit a "technical" ideal. tube guys have grown a sense of humor about this and distortion #'s do not matter and no longer explode into a thousand post thread of misunderstanding. They accept the technical flaw and get what they want from the sound.
Looking at these measurements there is no wonder that you will have people on distinct sides of the fence regarding these two speakers. They are dramatically different which debunks a few erroneous statements that all Thiel speakers sound alike. And also that the "lessor" models aren't as extended as the the moror? models. The 2.4 gives up 5 hz in bass extension to CS6 (somewhat insignificant to the original poster) and has a tweeter that is flat to 24Khz. And well since my preference is for Flat speakers with an excellent power response there's no wonder I like the 2.4 so much relative to the CS6.
I know most of you haven't done the research I have but the CS6 is an imaging machine, that dip in the upper mids is a trick found on the 2.3 and the early CS7 and about a thousand other wanabe high end speakers. Folks look long and hard at what a great imaging speaker measures like. And feel free to move through the remarkable amount of speakers that use this trick to image (Wilson Watt puppy's)etc.
Since I do not use my speakers like a TV, this is lost on me and the metallic tinge it creates to the violins leaves me cold. This is typically the price paid for great imaging a slight nasal character or metallic sound to strings, there are others but this coloration is very consistent from speaker to speaker.
Thing is if you like the CS6 this what you like and if you like the 2.4 that is what you like and nobody can criticize that opinion until you make unsubstantiated comments about better and best or is technically impossible.
I admit to looking hypocritical through my earlier post but it was to reach this end...have a good reason based in fact, audio is not some random crapshoot, there are real things going on that can be counted on and measured. there will always be a surprise here and there but that is the anomally not a reason to throughout the rules.
Review outlets are givng you some facts you can work with, use them to build some knowledge on real materials not some writers ability for digging superlatives out of the thesaurus. These products are expensive and if you care so much about it why not learn the facts not the BS.
I don't mean to belittle anyone and any insults by stating the obvious or what appears to be assumption about, anyone or any group and what those people know was likely a result of my writing for a wide audience and the effort to keep this as short as possible.
Thanks for reading my post,
have a good one
Doug