Need definitions of: Dark; Warm; and Bright

Just semantics but dark refers to a sound with treble and perhaps some midrange tipped down, warm to sound with an emphasis on midrange, where most music happens and bright is the opposite of dark.

You know them when you hear them.

Mapman summed it up nicely. 

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https://www.moon-audio.com/audiophile-terms-guide

https://www.audiophileon.com/news/how-to-describe-sound-an-audiophile-terminology-guide

https://www.stereophile.com/content/sounds-audio-glossary-glossary

I liken bright to shrill/ harsh though many may think that is an extreme comparison. To my ears that is what I hear. Warm is the sweet spot, feels good, sounds good, “right” if you will. Dark is heavy, defined but not in your face. Good lower end impact without much overtone. Being a drummer, these terms are often used as descriptors of cymbals, drums too at times, but always cymbals.