The 6 is much closer to the 3.6 than the 2.4 in terms of extension and ability to fill a larger room given sufficient amplification. Also, the dynamics will be greater due to larger drivers at the low end. I have the 6s and have listened to the 2.4s. They are very nice in that they convey the same accuracy but are better suited to smaller rooms or for envrionments where high sound pressure levels are not as critical. The 6s continue to be a statement product; Thiel has yet to replace this highly successful design, whereas the 2 series has undergone several changes over the years.
