The Master speaks
In a biography of ragtime pianist and composer Eubie Blake (“Charlestown Rag,” “I’m Just Wild About Harry”), the author recounted an incident of extraordinary perfect pitch. Blake had a tuning fork that he used to help the members of his band tune their instruments. At one rehearsal, a young woman musician who was touring with the company said, “Mr. Blake, your tuning fork is flat.” Blake was incredulous. How could a tuning fork be flat?
But the woman was insistent, so at the next town they went into a music shop and asked the shopkeeper for a brand new identical tuning fork. They struck both and heard the telltale “beat” of interference between two close, but not quite identical, frequencies. In rattling around in his suitcase, Blake’s tuning fork had become slightly bent, but the difference the young woman detected could only have been a few Hertz.
BTW, Cecil’s column about perfect pitch contained what I believe is a major error. In the last few paragraphs he conflates perfect pitch with the ability to read music and hear it in your head. AFAIK, the two are not related; you can have perfect pitch without being a strong reader, or be great at reading music and “hearing” a score in your head, without having perfect pitch.
Cecil seems to have spoken to someone with both skills and assumed that they were necessarily connected. They aren’t.
I know plenty of people with good relative pitch who can read and imagine the performance. I can read, and I can do it, but it works in reverse too – I can imagine what it looks like on paper upon hearing it.