New recordings from Bach to Villa-Lobos : GLASS: “SOLO PIANO.” Philip Glass, piano. CBS MK 45576(compact disc).

This music presents a kinder, gentler or at least quieter Philip Glass. “Metamorphosis” is a suite of five pieces, some based on themes from his score to “The Thin Blue Line.” The brooding neo-modal progressions and arpeggios often seem about to break into “Rustles of Spring,” but there is cumulative power here. “Metamorphosis” starts with numbing simplicity, but grows more complex in texture, richer in harmony throughout.

Then comes “Mad Rush” and “Wichita Sutra Vortex,” but you’ll have to count the track numbers to notice. There is scant difference in figuration or structural articulation between these pieces and “Metamorphosis,” although “Wichita Sutra Vortex” contains distinctive hints of 1920s popular music.