Need definitions of: Dark; Warm; and Bright

These terms mean nothing.

This sentence is literally talking about itself and its author.

Nothing but poetic license!

This one too.

Why must ignorance declare itself so boldly? Hmmm.

It’s seemed to obvious to mention before, but clearly it’s not: experience require *words* to be communicated. Experience of music can change when we compare with others and use new words. Happens with smell, too.

The point, Roxy, is that you don't always "know them when you hear them." You often need words to know them. This is why parents teach children the words for things and qualities in their experience. So they can know them, designate them in the future, compare them, etc. Without words, we're dumb brutes.

    doogiehowser       " Imagine if you had some amazing tool, let’s call it a frequency response plot (preferably with THD), that lets you visualize these things instead of guessing at them. Alas, the technology to create these magical plots is beyond most audiophiles."
What you describe is helpful, useful, and practical for those who seek visual confirmation of what they hear but of course for many audiophiles there is no need to "translate" what they hear in to another form entirely and completely simply for the joy, amusement, and entertainment of "seeing" a sound.

+1 @hilde45

here we are on this audiophile hifi music forum

all we have are words to convey thoughts, beliefs, feelings, experiences ...

A lot of none answers.

Warm refers to too much mid bass or a peak in the 100 to 250 hz region.

Dark refers to a trough in the 2000 to 3000 hz region

Bright is a rising response from 3000 Hz and above. Dull is a falling response from 3000 hz or anywhere from above.

My personal preference is for bass rising from 125 Hz down up 3 dB at 20 Hz and a falling response from 4000 hz down 6 dB at 20 kHz. This is at a 95 dB playback volume. The "right" frequency balance changes with volume. 

The tonality of a speaker system is based purely on it's frequency response. Things like enclosure resonances will show up as blips in the frequency response curve. Imaging is much more complicated depending on multiple factors. Then there is transient response and ringing. Tonality, however is totally "adjustable."  With many room control programs (a misnomer as it is really speaker control) you can program target curves to adjust tonality any old which way. Once you have programmed several hundred different curves you learn what doing this and that, here and there does to the sound. This is a great exercise for an audiophile.