Whoever takes the lead takes command, as it were, both of those few measures of music during which he or she is playing and, at times, of the entire piece. In some jazz recordings the personality of the lead dominates; this is especially true of performers the likes of Louis Armstrong, Sidney Bechet and Bessie Smith and the other classic blues singers. In other recordings the personalities of each of the performers emerges and contributes here and there in one chorus - or part of a chorus - without anyone single person dominating the entire 3-minute recording. This is the case, for example, in many of the early recordings of Billie Holiday, and the small group sessions of Benny Goodman both of which feature Teddy Wilson at the piano.
Trumpets seem naturally to lead in these bands, and are frequently expressive of a bright, quick, commanding personality, though when muted they may appear cautious or fraught. Although trumpets and cornets are different instruments, I can not tell them apart (except to by how they look). Louis Armstrong's dominant personality and impressively creative use of the instrument puts him at the front rank of any other trumpeters of the era. Other significant trumpeters include Joe "King" Oliver, Bix Beiderbecke, Tommy Ladnier, Bubber Miley and Cootie Williams, who played for the Duke Ellington Orchestra, Bunny Berigan, Buck Clayton, Henry "Red" Allen, Harry "Sweets" Edison.
Clarinets seem to encircle the melody with a flowing, freer obbligato line that can sound lyrical or soulful; its harmonious accompaniment with the melody sly, or reassuring. The clarinet has many tonal qualities ranging from high, bright harmonies to the chalumeau style, its darker, lower register. I think a particular characteristic of the instrument is its "woody" sound, though I am not sure I can say just what I mean by that. No single clarinet player dominates the early jazz era; some of the greats include Johnny Dodds, Barney Bigard, Sidney Bechet, Buster Bailey, Benny Goodman, Frank Teschemacher, Omer Simeon, Pee Wee Russell.
Both clarinet and trombone fill in the spaces left by the trumpet - and by each other and the rhythm section as well - and the complex textures of the ensemble playing requires great timing.Trombones can embellish melodies or respond to the voices of other instruments with plaintive or rambunctious counter-melodies, as well as provide deeply-toned rhythmic accompaniment and a darker, more resonant clarion call than the trumpet or cornet. The greatest trombonist of the era was Jack Teagarden, who was also an accomplished vocalist. Others include Kid Ory, J. C. Higginbotham, Miff Mole, Joe "Tricky Sam" Nanton.
The rhythm section, on the other hand, plays beneath the front line, holding it up, as it were, but also from behind, propelling it along by means of the various degrees of pulse provided by piano, drums, and various stringed instruments – banjo, guitar, bass fiddle – and in earlier numbers a tuba, which tends to give a slow, cumbersome, oom-pah feeling to the beat of the music. Drums help to create and maintain the 2-beat rhythm in 4/4 time, sometimes shifting into a backbeat on 2 and 4. Instead of feeling the beat at ONE two THREE four - ONE two THREE four we hear it as one TWO three FOUR - one TWO three FOUR.
The rhythm section does more than set and drive the rhythmic pulse; it states the harmony and plays the harmonic progressions – the roots of the chords - that underlie the melodies. Harmonies in jazz, and most music, are more than I can explain, but it helps when you listen if you are aware that the piece establishes and moves around a home key, the tonic, moving away from that to places in the music that make it seem far away from home, and then, satisfyingly, return. While such a little trip (as it were) may be felt as the melody unfolds, it is just as likely to be expressed and experienced through through harmonic progression, delivered by the rhythm section.
Members of the rhythm section will also step to the fore and take a solo; this is especially true of pianists.
Pianists from the early decades of jazz include Jelly Roll Morton, James P. Johnson, Fats Waller, Meade Lux Lewis, Jimmy Yancey, Earl Hines, and the big band leaders Fletcher Henderson, Duke Ellington, Count Basie.