In Jazz ,
Swing is a feeling which comes from the pulse being divided into one long note and one short note.
The long note is the "on" beat (important beat) and the short beat is the "off" beat and adds complexity to the music.

( not only because of the uneven feel, but also because tension notes can be placed on the off beat called grace notes AKA leading tones AKA embellishments. these notes on the off beat are typically set up as a half step resolution ( like from the V7 to I GBDF to CEGB) the B to C and the F to E are strong resolutions)

How swing works is you divide the measure into triplets. the long note takes up the length of 1 and 2 counts, the short (swung) beat takes up the 3 count 123,123,123,123 (Tick,ti,Tick,ti,Tick,ti,Tick,ti)


https://upload.wikimedia.org/wikipedia/commons/e/e9/Shuffle_feel_simple.mid


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https://upload.wikimedia.org/wikipedia/commons/a/aa/Blues_shuffle_in_E.mid
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Source
https://en.wikipedia.org/wiki/Swing_(jazz_performance_style)

 

 

Last edited: Apr 27, 2018

The best way I have found to "swing"

is to start with trplets.
123 123 123 123

next omit the second note, while having the first note last the length to the 3rd note
1*3 1*3 1*3 1*3


so you have your first note twice as long as the second note.

subsequently a strong beat followed by a weak beat.

this works right away for slow and medium tempos.

BUT ,when you want to speed it up fast, it sounds too goofy.

what you want to do is when going fast have the first note ONLY a tiny bit longer than the second note, this gives you a more smooth and fluid sound without a jagged feel.

practice this yourself

try going from triplet feel note length
gradually to each note being same length.

then once you are back to straight 8th notes again, go back a tiny bit in order to make the first note just barely longer than the second note and notice how smooth and fluid, yet expressive it becomes.