Some people call it "dixieland". Others find that offensive - since they find the yankee minstrel song "Dixie" to be offensive.
Some view the term "traditional jazz" as offensive, as those who created those genre(s) of music were striving to be anything-but traditional with it.
...I've decided to refer to it as "playing old songs". It's not specific enough, but neither is any term, and - one must admit - it's "inclusive".
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bandleader wrote:Let's play "Sweet Georgia Brown"...Hey bloke, what key?
You're going to want to play it in A-flat, beginning on F⁷, or leading from the tonic in the last bar back to F⁷.
not stated, as it's too much information, and would cause eyes to roll wrote:The original (published sheet music) key is G - as so much published music from that era favored easier violin and piano keys, but - since there's no fiddle - we probably don't want to play a bunch of E⁷'s and A⁷'s...
...so bloke tends to remember the best-or-traditionally-played keys of most "standard" tunes of this/these genre.
When some patron asks for a song that can be played in this/these styles, everyone knows how it goes, but isn't typically part of the repertoire, a bandleader might still ask, "What key, bloke?"
I quickly think through the song (rushing ahead to the highest pitch), figure out which scale step that highest pitch is, value that pitch at ether (concert) G or A-flat (which are fairly-high-yet-not-extremely-high pitches), figure out which of those two defined keys is an easier key, and then holler that key up to the band.