The old school of thought was that you have to be born with Perfect Pitch. You are either born with it or don’t have it at all. You can’t develop it if you’re not born with it.
I once watched and listened to a Hollywood musical director critique the performance of the band (with my teenage daughter playing clarinet) before their competition in San Diego the next day. I was amazed at how he could isolate from the multiple instruments playing, the ones that were off key, off beat or just not in sync for a unified performance. It was evidence that he knew the exact tones and chords of each instrument in the band, and obviously, recognized all of these by ear.
There are musicians who don’t even have this pitch recognition, but play well in a band or orchestra by having enough skills to play their instruments, reading their notes, practicing their parts religiously before they play and following the band leader for timing and inspiration, perhaps.
Perfect Pitch has to be the Holy Grail of musical achievement to transform one from appreciating music as a listener to being a performer and creator of music, alone or with others. With Perfect Pitch I could tell a B-flat from an F-sharp, by ear. It is an invaluable asset to have, for instance, for playing the guitar. Instead of strumming the guitar for chords by reading notes from a music sheet, I could step right in the middle of a band performance, and pluck those strings with the right chords, because I can hear and identify the chords by ear.
Is it possible that we all have this talent but just haven’t developed the ability to let it out? Or, don’t have the training or tools to do so?