The Impressions Reunion show at DAR Constitution Hall Saturday night offered an impressive musical performance and an enlightening journey through some of the major changes in black music's style and content over the past 25 years. Resplendent in white tuxedos, the four original Impressions and two latter-day members presented a lengthy program that covered not only the Impressions' musical history, but also the solo careers of the group's most illustrious pair, Jerry Butler and Curtis Mayfield.

One of soul music's significant innovators and most eloquent poets, the cherubic Mayfield presided over the musical events with guitar in hand and the satisfied grin of a parent pleased that his children have turned out so well. The audience was particularly delighted when Mayfield, joined by original Impressions Fred Cash and Sam Gooden, applied his wispy falsetto to such mid-'60s hits as "I'm So Proud" and "It's Alright." This trio's lilting gospel harmonies were particularly moving on the anthem "People Get Ready," a soul classic that magically conveyed the same optimistic and prophetic spirit of social change that it did in the civil rights era.

The ever-suave Jerry Butler needed no introduction. His rich, sonorous baritone was instantly identifiable when he turned in a powerful rendition of "Make It Easy on Yourself," before moving to his sophisticated Philly-soul hits such as"Only the Strong Survive" and "Western Union Man." Mayfield's solo segment was devoted to the innovative light funk he patented in the early '70s in street-wise poems like "Superfly" and "Freddie's Dead." Later, all the Impressions joined Butler for a gloriously romantic rendition of the group's first hit in 1958, "For Your Precious Love."