History: What is the color of a sound?

What is the color of a sound?

• How loud or soft a sound is.
  This is amplitude.
• What makes one sound source sound different from another.
  As close as one can describe it!
• How high or low a sound is.
  This is pitch.
• How amplitude is distributed over a set of frequencies, over time.
  Close, but this answer is a physical description, not perceptual.