[DanDan]

Ethan, there is a great advice (from one of your Presidents I think?) :- " It is better to keep ones mouth shut and appear a fool, than to open it and remove all doubt."
So, completely ignoring that, I would be happy to join a discussion on how various materials 'sound'. I do however think it best to start a new thread with an appropriate title, and I still think this one should be culled.

I, like you, have gradually removed quite a few of the myths and contradictions in my own mind, and would happily share this.
e.g.
Wood, presumably reasonably hard wood, with a surface finish, mounted somewhat resiliently, sounds bright in a listening room. However, a recording of an acoustic instrument in a room with a significant amount of such wood, sounds warm. Go figure. I have no need to prove this. I can extrapolate from my listening and recording experiences. I could take a few bits of Physics and Maths to further shore up my observations, but is there hardly a need.


Absorption Coefficients are typically measured in a historic manner. The method reflects the intended use in the field of Building Acoustics.
This field is more concerned with Noise than 'Sound'. I reckon any attempt at putting numbers on a 'Sound' or perhaps 'Tonality' in the context of recording or listening to music, has to be full range. Omitting below the 125Hz and above the 4kHz Octaves is ignoring three musically vital octaves. Furthermore those Coefficients apply to a diffuse sound field, which doesn't exist in our listening rooms. There are a couple of other factors, but clearly that set of numbers is not musically complete and it is not mathematically applicable to our rooms.

Regarding Concrete vs Wood. I believe the only test which would answer our enquiring minds would be to take a finished treated listening room with a finished Concrete floor. Measure it in terms of averaged Frequency Response, EDT, and whatever you fancy. I also recommend playing reference music over the speakers and recording it with a high quality stereo pair, suitable for later headphone listening. Install a wooden floor. Repeat the process using the same measurement locations. Wouldn't that be interesting?

Alton Everest had many great wisdoms.
My favourite paragraph of his is:-
The pioneering scientist was right when he said 'to measure is to know'
Only in this way can subjective factors be controlled. However the very act of hearing is subjective and the trained ear might very well detect flaws in a studio, elegant graphs and measurements to the contrary. This does not mean that measurements are worthless. It only means that if one is processing programs for ultimate consumption by the human ear, a trained ear and measurements must supplement each other. The science of acoustics has grown to maturity during the past 100 years but there is still something of an art about it's practice.

Warm Regards, Dan FitzGerald