Brendon Urie has described his synesthesia in interviews over several years, most vividly to Rolling Stone in 2018: hearing a song can mean seeing colors, a tornado of circling words he picks one out of, or shapes, a song as a square in perfect order, or a pyramid turning into a rhombus. His account is notable for its breadth; the experiences shift form, and he ties them to emotional state rather than a fixed code.
He has also described whole records in color. Death of a Bachelor, in his telling, lived in bright yellows and reds with soft Sixties pastels and dark, popping teals, a palette description specific enough to hand to a designer.
Urie’s case sits comfortably in the self-described tier: repeated firsthand accounts across years, given in his own words, with the idiosyncratic specificity that genuine reports tend to carry.