Does carpet deaden the sound too much?

Use spikes for the speakers.  Make sure they rest on a hard surface.

+1 on this @erik_squires 

The spikes under the Isoacoustic Gaias made a big difference compared to the granite plinths I had under the speakers. The speaker feet now directly couple to the concrete floor below.

In my system, the floor carpet helps tame a lot of echo. The music sounds very lively and nothing sounds dead. Experiment with the wall treatments and remove some if you find they deaden the music. Do you have treatment at the second reflection point? If yes, experiment with that.

@ curiousjim, i have a mcintosh mc602 amplifier with 600 watts per chanell powering my 4 901's! sounds great to me!LOL!!

@rixthetrick, with a mcintosh mc602 with 600 watts per chanell i guess carpet would'nt matter in my case!

In my experience having my systems in 3 different rooms with different flooring throughout the years, the best sound comes from wood/tile floor with a thick rug in front of the speakers. A fully carpeted room sounds a bit dead but that can be resolved if diffusion is added to the ceiling and/or walls for balance. If the speakers are inherently bright then perhaps nothing is required to be done.

@g_nakamoto We were lent a pair of McIntosh MC501 with the matching pre for at least 12 months some years ago, while the development of a customer's pair of speakers was undertaken.
They sure had some drive, so yeah I'm thinking you're not going to lack energy in your room at all.

I have only got 400 Watts a side and I don't use even close to nearly all of it ever.

@hiendmmoe - have you any thoughts about the varying responses so far?