i'm looking for ways on working it out on an instrument, rather than a software

Thanks

 

Knowing the basics of harmony helps a ton. Experience will make sure you recognize the key of a song in few seconds.
You can help yourself by playing the melody on your keyboard. Notice the alterations (black keys). All root keys have just so many alterations (with a few exceptions by genre, which make recognizing the root key a little more difficult). But for most pop songs, it should be enough.

If you check online, you can easily find out how many alterations are in each key. For instance, if your melody is playing a C#, you can (in most cases) safely assume your root key is not an A minor, since C# is not in the scale of A minor.

But if you want to become an expert at recognizing root keys, you should definitely learn at least the basics of harmony.

 

Last edited: Aug 26, 2020

I just use that old "hum (when track is playing) to find the tonal center" thing, then use guesswork / playing to find key / mode. It usually takes a few seconds. We have a lifetime of experience, best to just use it! Also: theory helps if you get stuck.

 

virtual dj

 

I just pick up my guitar (or sometimes the keyboard) and jam along. Normally doesn't take me too much to figure out the tonic and then if it's major or minor.

 

It was already discussed several times in this forum.

Have a look to this:
https://audiosex.pro/threads/recreating-melody-by-ear.45195/

and this:
https://audiosex.pro/threads/i-need...scale-chords-of-a-specific-piece.52882/page-2

There you'll find practical examples on how to find keys, scales, modulations, etc. (I did it!).

 

Finding the tonic (center of gravity) is usually pretty simple. Then it's just a matter of finding the key. 8 times out of 10 it's either major or minor, but once in a while it's mixolydian, phrygian, dorian, etc.

 

The trick to find the key is to first know yourself.
That is the essence.
If you have a message in a song, then you write it automatically.
That is the key of self awareness.