I began by listening to a C. After a week I could find it reliably every time. Then I did it for all the other notes. On bassoon I recognize all notes by their

I began by listening to a C. After a week I could find it reliably every time. Then I did it for all the other notes. On bassoon I recognize all notes by their timbre. When I did this it started being something else. After a while I didnt recognize the notes. I just knew. I sometimes still have this. My harp colleague plays a note and I just know what it was. I told this to a friend of mine who teaches solfege at college level (royal Danish conservatory) and she said that in her line of work perfect pitch isn't a gift it is a work-related injury.