Listen this sounds like some buddha type shyt but its true...
Let the sound come to you, just listen to it. dont listen into the sound, let it fully soak into your ears. And you'll realize that it has a sound completely different from all the others.
now as you listen more and more, the sound you once heard will start to evaporate. this happens! you just got a taste of pitch recognition, you just have to practice it like 5 mins a day just listening to each individual note.
you'll learn these tones more and more. and as you listen you'll start hearing more characteristics of these sounds, like the F# not only sounds buzzy but it's also very bold.
F# is an attention grabber, now when they say you'll be able to identify the key of a song. you'll notice, the songs that really stick have some relation to F#.
have fun.
"My whole life is a dark room...ONE BIG DARK ROOM" - a.f.i.