What does 'cold' mean? What does 'warm' mean?

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But audio experience cannot be reduced to these qualifications....They are too gross...Audio experience is linked to the more deep question : Is the recording of this piano timbre like my audio system render it to my ears, in my room acoustic, is this piano timbre natural ? Neither cold nor warm, just right and more neutral than not ,and natural like in real life experience?

This is the question....

Happy New Year geof3....

Wow whats that?

"Warm is used by a salesman to encourage you to buy their product.

"Cold" is used to criticize a product. A salesman may use this to discourage you from this item.

Another descriptor with a positive connotation that I like is "meat on the bones".

If you're dealing with a system, or a sound, in which no agreeable balance can seemingly be struck between warm and cool, i.e. a sound that can be made to be either too cool or too warm, but offers little or no real appreciable apparent, or satisfying, 'sweet zone' in the middle, then you have a sound that is said to have little or no "inner warmth". 

A system or sound with a good deal of inner warmth will, by definition, sound neutral without also sounding threadbare. As opposed to an overtly warm sound that may be described as 'pleasing', but strictly speaking is neither accurate nor neutral.

Universally accepted as terms, but for me neither is correct when it comes to balance or neutrality.
G