Mr. Boulez strives for a balance between intellectual control and improvisatory freedom, and gives performers frequent choices.

Mr. Tetzlaff brought improvisatory freedom to these curious passages yet made every restless run come across as part of an integral conception.

Courtenay in contrast delivers some of his greatest works with the improvisatory freedom, and virtuosity, of one of Larkin's beloved jazz musicians.

The other approach was the contrapuntal fantasia, in which long, complex passages of counterpoint evolve with a miraculous blend of compositional rigor and improvisatory freedom.

The goal, turbo-boosted by black political activism, was total improvisatory freedom.

The rhythms of 1930's swing and the improvisatory freedom of jazz were intrinsically unsettling when what was required was unisons, resolutions and predictability.

Unlike his former sideman Coltrane, who aligned himself with the avant-garde and ultimately became its prophet, Davis sought a middle ground between improvisatory freedom and adherence to form.

Every composition involves a tension between systematic law and improvisatory freedom, between implicit expectation and explicit surprise.

Yet for all this evident micromanagement, Mr. Schiff's readings flowed with a natural, almost improvisatory freedom.

At the very end, the piccolo player injected a delightful improvisatory freedom that he might not have ventured had he been focused chiefly on blending with his colleagues.