When he was a teenager, the jazz pianist Bill Charlap recalled at the 92nd Street Y on Tuesday evening, he met the composer Jule Styne and asked him for the secret to writing a good popular song. Mr. Styne, choosing his words carefully, replied that it had to be "melodically simple and harmonically attractive.â€
Mr. Charlap used the Styne tune "Just in Timeâ€ as an illustration. The melody's nub consists of two adjacent notes repeated again and again, with some rhythmic variation. A sense of musical movement is created mostly by the changing harmonies under the motif. Mr. Charlap, a keyboard wizard who continually surprises, went on to inflect the song's Broadway chords with his own jazz modulations and deliver an exquisite piano solo free of clichÃ©s.
This demonstration was one of several pertinent music lessons inserted into "Sondheim & Styneâ€ on the second night of the Y's Jazz in July Summer Festival, which runs through next Thursday. The concert put the show tunes of Mr. Styne and Stephen Sondheim through the jazz wringer and found a natural compatibility between the genres. It wasn't so long ago that Mr. Sondheim's music was considered too rigorously composed and hermetic to be readily open to the kind of improvisation invited by older popular standards, with their more relaxed melodies. That may be true, but only in a limited sense.
Taut as it is, a song like "Another Hundred People,â€ from "Company,â€ with its elaborately syncopated staccato syllables, is a ready-made jazz song. As the suave, jazz-crooning dandy Kurt Elling performed it with an ensemble that included Brian Lynch on trumpet, Jimmy Greene on tenor sax, Jon Gordon on alto sax, and Mr. Charlap's regular trio members Peter Washington on bass and Kenny Washington on drums, it suggested an artful cacophony for voice and traffic sounds.
The concert, in which Mr. Charlap alternated on keyboard with his wife, Renee Rosnes, an excellent pianist with a more fluid, straight-ahead style, reasserted the strength of Mr. Sondheim's music, independent of the lyrics. Disregarding its sentiments, Mr. Elling treated "Not While I'm Aroundâ€ as a vehicle for exploring abstract vocal tones, drawing out syllables at the ends of phrases and stretching the rhythmic format. One of his signature mannerisms is to hit the top of a note and bend it slightly down, a technique that might also be described as singing a quarter-note sharp, then adjusting the pitch.
The concert's most magnificent moment belonged to Mr. Charlap, who delivered an astonishing "Some People,â€ from "Gypsy.â€ After a "Flight of the Bumblebeeâ€-like introduction, the song took off with a slingshot propulsion that carried it through furious, turbulent changes covering the entire keyboard; it left me breathless. Mr. Charlap also tipped his hat to Mr. Sondheim, the lyricist, by prefacing a bluesy, swiveling "Uptown Downtownâ€ with one of his favorite quotations from the song:
She sits at the Ritz with her splits of Mumm's
And starts to pine for a stein with her Village chums,
But with a Schlitz in her mitts down at Fitzroy's Bar,
She dreams of the Ritz, oh it's so schizo.