Many thanks to all of you. This discussion has been very helpful even though I'm still not sure I completely understand. I know the Wilson Watt/Puppy series is consecutively numbered with each greater number arguably an improvement on the prior model number. It's a shame the Thiel numbering system couldn't be as clear.
Thiel speaker model range
Does anybody have a list of the various speaker models? I haven't been able to find anything. For instance it would appear that the CS6 would be better than the CS2.7 but maybe that isn't so. I am in the market for a Thiel set but don't know what to look for in the used market. I heard a set of Thiels with YBA preamp and Electrocompaniet amp and they were glorious. I don't know the Thiel model but they were large.