Establishing Tonal Center in 'Real Music'

[giggsy11]

Hi, everyone. Posted this on Reddit but feel I might be able to get better answers on a dedicated music forum.

So for the past three months now, I've spent some time on the Functional Ear Trainer app (for those who don't know, basically an app that establishes a tonal center by playing a I-IV-V-I cadence followed by playing a note in that key which you have to identify) and have gotten pretty good--I can tell which diatonic note is being played in any random major or minor key, in any octave, with 95% accuracy. There is also a mode in the app that lets you play X amount of notes after the cadence, and I can identify in real time up to 5 notes at 100 bpm.

Now the issue I'm having is translating it to 'real music.' I think the reason why is because songs aren't as explicit in establishing the tonal center as the app is (they don't begin with a I-IV-V-I cadence before getting into the actual song). It could also be because there's also so much more going on in a song than just the melody line that the rest of it obscures how well I'm hearing each note in the melody in relation to the tonic.

I'm also not good at establishing the tonal center for songs that are just a melody line. Take, for example, something as simple as "Happy Birthday." While I know the tonic is the final 'you' in the song, each scale degree used doesn't have the same 'color'/feeling it usually does when it's played after the I-IV-V-I cadence. A Sol/scale degree 5 in the Functional Ear Trainer has a very distinctive sound such that it can only be a Sol, whereas the Sol that starts Happy Birthday might as well be any note/scale degree to my ears.

So I'm wondering if you guys have any advice on how I can get better at hearing notes as they relate to the tonal center in both the above described scenarios. I know this is something that's probably going to take a lot of time, but I'd appreciate suggestions for a plan of attack at getting better at it. Thanks!

[rick-slo]

I don't have a rule that fits it all answer. Sometimes it takes some ways into a tune to decide what the key is. For example in an opening chord sequence
such as D#m7b5-G#7-C#m7b5-F#7-Bm7b5-E7-A. Some tunes go in and out of different keys and/or make use of a lot of chords containing chromatic notes.