Understanding the structure of the music is the first step toward an increased appreciation of it. The rest of this primer will deal mainly with hands-on musical examples. Before you delve into the theory, however, you need to develop a feel for swing. This is part of the rationale behind doing so much listening, since it is virtually impossible to teach swing analytically. Nonetheless, I will try to explain what you should be hearing and trying to achieve in your own playing.
The most basic element of swing is the swing eighth note. In classical music, a set of eighth notes in 4/4 time are meant to take exactly one half of a beat each. This style is called straight eighth notes. Play a C major scale "C, D, E, F, G, A, B, C" in straight eighth notes. If you have a metronome, set it to 96 beats per minute. Those are quarter notes, "one, two, three, four". Subdivide this in your mind, "one and two and three and four and".
A common approximation to swing eighth notes uses triplets. The basic beats are be subdivided in your mind as "one-and-uh two-and-uh three-and-uh four-and-uh", and you play only on the beat and on the "uh". The first note of every beat will be twice as long as the second. This will sound like Morse Code dash-dot-dash-dot-dash-dot-dash-dot and is far too exaggerated for most jazz purposes. Somewhere in between straight eighth notes (1:1 ratio between first and second note) and triplets (2:1 ratio) lie true swing eighth notes. I cannot give an exact ratio, however, because it varies depending on the tempo and the style of the piece. In general, the faster the tempo, the straighter the eighth notes. Also, pre-bebop era players often use a more exaggerated swing than later performers, even at the same tempo. No matter what the ratio, the second "half" of each beat is usually accented, and beats two and four are usually accented as well. Again, the amount of accent depends on the player and the situation.
There is also the issue of playing behind or ahead of the beat. When Dexter Gordon plays, even the notes that should fall on the beat are usually played a little bit late. This is often called laying back. It can lend a more relaxed feel to the music, whereas playing notes that should fall on the beat a little bit early can have the opposite effect. Bassists often play slightly ahead of the beat, particularly at faster tempos, to keep the music driving forward.
Not all styles of jazz use swing in the same way. Most Latin jazz styles and many fusion and modern styles use straight eighths, or eighth notes that are only slightly swung. Shuffles and some other rock styles use very exaggerated swing. Listen closely to recordings in different styles, paying attention to the differences. Do not be fooled into thinking that swing is a universal constant.
Learning to play natural sounding swing eighth notes is often the hardest part of learning to play jazz, since it can sound so bad until you can do it well. There are some techniques that can help you overcome this initial awkward stage.
If you have been listening carefully to other musicians, you may be better at recognizing swing than at playing it. Therefore, I highly recommend recording yourself playing swing eighth notes at various tempos, and then listening to yourself on tape. You can judge for yourself whether your swing sounds natural or forced. It has been said that if you cannot swing unaccompanied, you cannot swing. It is important to work on your own concept of swing in this way so that your perception of how you sound is not influenced by the sound of your accompanists.
You should work on your swing no matter what you are playing. When you practice scales, work on swing as well as simply playing the right notes. Try varying the rhythm you use to play the scale. In addition to scales, you should try practicing swing when playing other exercises or songs. Any practice method book or fakebook will probably contain several appropriate pieces. Try playing songs with many consecutive eighth notes, but also try songs with longer notes and rests. Having to play many consecutive eighth notes can make you too self-conscious of your swing.
While being able to swing unaccompanied is important, it is not easy to do at first, and when developing your swing concept, it can also help to hear it occasionally in the context of a group performance. One thing that would help at times is to have a rhythm section accompaniment. If you have Band-In-A-Box, you can program it to play endless choruses of C major, and then you can practice playing or improvising on your C major scale while working on your swing. Aebersold records can provide accompaniment as well, but be aware that most of the tunes have many chord changes and are too complex to use for this purpose. There are a few suitable tracks, however, such as some of those on Volumes 1, 16, 21, 24, and 54, which are geared toward beginners. The books included with these, especially the first four, also contain some useful instructional material.
If you have a partner, or a tape recorder, or a sequencer (computer hardware and/or software to record and play back on a synthesizer) you can create do-it-yourself accompaniment. The basic components of a swing drum beat are the ride pattern and the hi-hat pattern. The ride cymbal pattern, at its most basic, is "1, 2 and, 3, 4 and"; or, phonetically, "ding ding-a ding ding-a". The eighth notes on 2 and 4 should be swung, of course. The hi-hat is closed (with the foot pedal) on 2 and 4. Walking bass lines can be constructed by following a few simple rules. First, play quarter notes. Second, keep them in the two octaves below middle C. Third, play only notes from the scale on which you are working. Fourth, most notes should be only a step away from the previous note, although occasional leaps are acceptable. For instance, a C major bass line might consist of "C, D, E, F, G, E, F, G, A, B, A, G, F, E, D, B, C". You will need a lot of patience to create your own accompaniment with a tape recorder, since you will want to record many measures so you do not have to keep rewinding the tape when improvising later. A sequencer will allow you to set up loops, so you can record only a few measures and have them repeat endlessly.