How can I tell what key I'm playing in?

[PaulT]

(ok, I know, this isn't a banjo forum...)

I play by ear a lot and have worked up several arrangements I like. But, I don't know what key I'm playing them in, I just play them. And it has occurred to me that if jamming opportunities present themselves once playing with others starts up again, it would be good to know what key I'm doing something in just in case someone asks, "say, what key is that in, I'd like to play along".

It isn't as simple for me as it is with guitar (why, it's in G of course).

How do you tell what key you are playing something in? Is there a quick way? Or do you map out all the notes and if those three are flat and these three aren't, by process of elimination it must be Eb. Or do you play different scales and see which one fits within the particular song? Or do most players just "'know".

[Burgerbob]

Well, even if you're playing by ear, you should generally know what notes you're playing and what you're centering around. It's important to be able to tell what note you're playing over the chord you're hearing (which will also tell you the key sometimes).

[Doug Elliott]

Interesting dilemma. It would help to know what you DO know, to figure out what you don't. What is your musical background? Did you learn to play entirely by ear, or reading? Do you know your scales? Do you know if it's major or minor? Can you post a recording of what you're doing?

[robcat2075]

In college music theory classes we were warned not to use the term "key". Only amateurs said that!

"Tonality" we had to say. The tonality of a piece is the tonic note, the note on which it sounds complete, finished, home.

Play that note and you have your "key". Easy to hear in most classical music. Less so in jazz.

just in case someone asks, "say, what key is that in, I'd like to play along".

Yet another awkward social situation

[imsevimse]

Generally if you limit this to easy stuff like folksongs they all end on a note that also is the key of the scale which then also is the key of the song. If it ends on Bb it often is Bb-major or Bb-minor.
To be able to hear the difference between major and minor is also a skill. Many suggest minor to be more melancholic and major to sound more happy, and I can agree this is often the case, but there are a lot of minor variants.

This is not bullet-proof because as son as songs becomes more advanced they can change key within the same song and they can also contain modulations so they gradually change keys. This can happen several times within more complex tunes. Jazz-tunes and improvised solos often ends at other notes than the key note.

I suggest to learn the theory. Get a book or Google. The theory helps a lot when you learn a tune by ear too.

/Tom

[timothy42b]

I work a little bit on playing by ear every day. It's a skill I've never had, and thought I never could learn, but I'm making a little progress.

So i pick a tune I know, something fairly simple. I figure out what degree of the scale it starts on. Like, Happy Birthday starts on 5 (sol). Then I pick a key. In the key of Bb, I'm going to need to start on F. Then I think the interval that comes next and try to play it. I try to know the interval and the note I'm on. When I play a note by muscle memory I lose my place and crash. It would be nice to also know what the chord is but that's too advanced.

I have trouble understanding how you can do it without knowing what key you're in.

[Pre59]

This is not bullet-proof because as son as songs becomes more advanced they can change key within the same song and they can also contain a modulation so tgey change key, and this can happen several times within more complex tunes. Jazz-tunes and improvised solos often ends at other notes than tge key note.

/Tom

"Unforgettable" the hit for Nat King Cole being a good example. It starts in a major key, and ends in in a major key but a fourth up, needing a modulating turnaround back to the home key for repeats.

[PaulT]

Thanks for the responses.

Turns out the answer to the question was in the asking.

I had never thought about what key I was playing the songs in, I just found a place that felt good and sounded like I wanted it to and played them. But, once I started thinking about the notes "ok, the A is flat", "hmm, the B is natural", "what is up with the F?" and played around with scales that fit within the song, that pretty much did the trick. (I did have to write one out. Turns out I do "I'm Getting Sentimental Over You" in Ab major... I can't hit a C# but G is in my all day wheelhouse)

I had never thought about what key I had settled into for a particular song as I never had reason to. But, now when our band gets back together again (most of us should be shot up by Spring) we're talking about putting some small groups together and, well, who knows, but if the opportunity presents itself, I'm calling out "All of Me" in C, guys!
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