People born with absolute pitch (AP) can, without either reflection or comparison with an external standard, identify the pitch of any note, right away.
They can do this not only with any note they hear, but with any note they imagine or hear in their heads.
For most of us, such an ability to recognize an exact pitch seems super-humanly astonishing.
It is almost like another sense we can never hope to possess, such as infrared or X-ray vision; but for those who are born with AP, it seems perfectly normal.
Most people with AP can identify over 70 keys in the middle of the auditory range. (A piano has 88 keys).
For them, each and every of these 70 tones -- every key seems qualitatively different, each possessing its own “flavor” or “feel,” its own character.
While extremely rare in the general population AP is relatively common among professional musicians, and to a limited extent may serve as a marker for musicality.
Those who have AP often compare it to color—they “hear” G-sharpness as instantly and automatically as we “see” blue. (Indeed, the word “chroma” is sometimes used in musical theory.)
Researchers estimate the occurrence of AP to be 1 in 10,000 people [0.01%].
Back in late 1994, my piano teacher, Mr. Benny D’Silva never failed to astound me with his sense of AP.
Sometimes he would be teaching children in an inner room, science or mathematics, and whenever I struck a wrong key on the piano, he would hear it, identify it, come running to the outer room, where I was playing on his upright piano, and say,
“ ‘D’, Ram Rao! You played a ‘D♯’ !”
Sir Frederick Ouseley, former prof. of music at Oxford, had a remarkable sense of AP, all his life.
At the age of 5, he was able to remark, “Only think, Papa blows his nose in G”.
He would say that it thundered in G or that the wind was whistling in D, or that the clock (with a two-note chime) struck in B minor.
When the assertion was tested it would invariably be found correct !!