I have a couple of friends who hear music as colors. I am casually obsessed with this topic. I taught piano lessons to a kid who would say this is blue, green…etc.
I copied this out of Synethesia Wiki:
from the Ancient Greek σύν (syn), “together,” and αἴσθησις (aisthēsis), “sensation”—is a neurologically based phenomenon in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway.  People who report such experiences are known as synesthetes. In one common form of synesthesia, known as grapheme → color synesthesia or color-graphemic synesthesia, letters or numbers are perceived as inherently colored.
I wonder if there is a correlation between the visible color spectrum and Synesthesia.
A typical human eye will respond to wavelengths from about 380 to 750 nm. In terms of frequency, this corresponds to a band in the vicinity of 790–400 terahertz.
Here is a hypothesis; Maybe people who have an acute sense of hearing are able to hear terahertz, which enables them to distinguish some sort of color from the sounds they hear.
I am very curious about this topic. How people experience sound. Please share on this post.
I will begin one:
I experience sound and songs with some color, but more as a 3 dimensional space with momentum and movement. I see things as a connected thought that is visually represented. This visual representation also seems to move at what is a bpm. This is my experience when listening/performing “experiemental music” or more traditional concepts of songs and song structure.
…Ok so your turn….