If I can learn to play in jazz style, so you can you! You already have everything you need in your classical organ tool box. And you have YouTube! So, go on-line and see what you can learn just by listening. Much of the music I listed in the June TAO article are being demonstrated there. Mostly, what you need to develop is an ear for what jazz “should sound like.” As your ear develops, you will have an auditory target for what you want your piece to sound like, and you will be able to confirm correct playing as you practice. This alone will speed you along your way.
There are three skills that will move you toward making an authentic jazz sound. The first is learning how to apply what you already know about agogic accents to jazz. Agogic accents are simply the organist’s way of emphasizing and de-emphasizing selected notes in a rhythmic pattern. You already know how to emphasize the downbeat by shortening the upbeat just before it, right? The same thing applies to jazz. In addition, Wwe need to pay careful attention to the lengths of notes. If you were to look at a big bang score, you would notice the amazing amount of detailed markings over the notes: staccatos, tenutos, accents, and everything in between. You should do the same as you study the score you are preparing. The visual cues help you to anticipate the kind of touch you need to apply to achieve just the right musical line.
The skill of rhythmic note differentiation can only be accomplished in relation with the other two skills, backbeat and swing. What did Duke Ellington mean when he said, “It don’t mean a thing if it ain’t got that swing?” Simply stated, the sense of swing is accomplished by emphasizing the second and fourth beats, instead of the classical emphasis on one and three. In order to get a sense of the difference, set your metronome (app) on 4/4, 60-80 bpm, then count out the two different ways. When you get how two/four backbeats work, let all your playing decisions center upon supporting this pattern. Believe me, your body will respond to everything you play differently once you learn to relax and trust it.
Now that you have the two/four backbeat engrained in your technique, the only thing left to do is understand that eight notes are counted as triplets. This gives them an unevenness that is valued in the jazz line. Essentially two eighth notes become a quarter/eighth triplet. This can become tricky when you try to coordinate the left hand accompaniment/walking pedal patterns that are common. Just remember to defer everything to the triplet pattern, even in the left hand accompaniment. Jazzers like to emphasize notes that land on that last triplet before the next beat, which adds to the unevenness we just mentioned.
This will seem like strange territory for a while. As I said, a little listening goes a long way toward giving you confidence to keep at it. And keep at it you must! No risk, no reward. Let me know how you are doing!
Chris