As someone who doesn't have perfect pitch, I always need to have an instrument around to write sheet music for a song.
If I know the key already I can figure out melodies but not more complicated chords and key changes, without playing around on my instrument before.
Is there a way to learn perfect pitch because it seems it's something you either have or not. Or any other method so I don't need to constantly pitch-check? Hope I was clear enough :)