CMIIW, Warm, is more emphasize on Low (bass), with decent of Mid (vocal), and sometimes a bit spark of High (Treble).
The more detail the rumble (sub Bass), some time it sacrifices Micro detail from High (treble).
Cold / Bright , is the other way around of Warm. which more emphasize on Mid and High.
Large sound stage, micro detail, I find correlate to Hi Mid and High (treble).
Why Solaris sounds so wide and tall in sound stage, because the spark (high/treble)...
IMHO...
https://www.headphonezone.in/blogs/audiophile-guide/sound-signatures-explained
simple reading...