Does carpet deaden the sound too much?

The proximity of the speakers to the floor means it is the very closest first reflection point, unless you have speakers sitting right besides walls (even if you have to downsize the listening triangle, bring speakers off the side walls if you can), it's the closest surface.

Obviously I don't know what you're using, speakers, amps, front end or even the size of the room? If you have your speakers toed in, or what other room treatment you may or may not have?
The floor coverings would not be the first place I'd go hunting for the lack of lifelike presentation. And musical instruments are often bright, sharp and startling sounding in real life, so yeah I can see you'd want that. Flavor!

Your question, for any of us trying to respond with useful information will require enquiry - This opinion is based solely on the assumption that your response coming off the floor is predominantly off axis. The midbass and tweeters should not be firing at the floor, they should by varying degrees be aimed at your head (ears).
On axis for full impact, slightly off axis to attenuate brightness, with your listening apparatus on the same plane as the tweeters  - in general.

If the floor entirely absorbed every bit of energy it was presented, it shouldn't make for more than a meager portion of the voicing of your loudspeakers, if the tweeter is at ear height with you sitting in a standard listening chair.

Please by all means elaborate on what you're using, and in what conditions it's playing?
 

@holmz - he's asking if too much absorption is a possible reason for the system not sounding lively.

I say, very unlikely that this singularly would be the culprit.

Does the carpet affect the overall sound (matter)?
I expect it does affect the overall sound, as others have shared.

In a positive or negative manner, well that's for you to determine.

@retiredfarmer - Hi Tom
Many of us now decouple using springs, others have had success with other technologies. There are entire threads on isolation with some really positive responses.

@hiendmmoe - can you share with us some information about your room and system?
Room dimensions, any treatments used, speakers and electronics?
Genre of music most enjoyed when listening?

Also, completely differently, try disconnecting all cabling & cleaning the cable ends & whatever socket or connecter they go into & replacing them.

+1 a 100%

@g_nakamoto - did you read what fatdaddy2 wrote?

If you want to experiment, get yourself a couple of sheets of 4x8 ABX plywood, and place underneath and in front of your speakers. Do you like the difference in the sound? A lot quicker and cheaper than tearing out your carpeting for wood or other hard surface flooring!

You could always cut the boards up to make diffusers when you’re done.

@hiendmmoe - Oh man, I can’t believe I didn’t at least have a look to see if you have a system page. After seeing it, wow cool gear mate. When did you last clean all connectors, someone reminded me and yeah it livened up immediately.

@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?
 

I favour a broad-band absorber on the ceiling preferable to carpet as a means of dealing with floor to ceiling absorption.

Great, this is the area in which I need more information in order to make an informed decision. I know that my next move is on the ceiling, and your position of broadband absorption aligns well with what I have been reading.

How to implement that, for my particular needs, that I am very unsure of.
@lemonhaze - I’d like to know more about what you’ve done, how you went about it, researched it, implementation and resulting impressions please?
I can take it to DM (PM) if you’d prefer, as I am really interested, hopefully you're willing to share it?