Rhino Records (each volume a separate CD), $16.98 per volume: Vol. 1—George & Ira Gershwin, R2 71503 ( CODE: RHR -6);

Vol. 2—Johnny Mercer, R2 71504 ( CODE: RHR -7);

Vol. 3—Rodgers & Hart, R2 71505 ( CODE: RHR -8);

Vol. 4—Irving Berlin, R2 71506 ( CODE: RHR -9);

Vol. 5—Duke Ellington & Billy Strayhorn, R2 71507 ( CODE: RHR -10).

The people at Rhino Records, the premier compiler of old popular music on CD, have come up with the happy idea of a series of discs devoted to classic versions of great songs by the great American songwriters, one disc of twenty songs to each songwriter. On the Gershwin disc, Tony Bennett sings “How Long Has This Been Going On,” Jo Stafford swings “Embraceable You,” Chris Connor breathes “But Not for Me,” Ella and Louis pair up for “They All Laughed,” Bing Crosby croons “Somebody Loves Me,” Sylvia Syms knocks out “Love Walked In,” and so on. The selections all seem just right: On the Johnny Mercer album, who else but Sammy Davis to sing “That Old Black Magic,” and who better for “Hooray for Hollywood” than that great nightclub-voice-gone-Hollywood Doris Day? Other high points: On the Rodgers and Hart album, Chet Baker’s “My Funny Valentine” and Billy Eckstine’s “Blue Moon”; on the Ellington and Strayhorn, Harry James’s classic “I’m Beginning to See the Light” (with Kitty Kallen) and Mel Tormé’s suave “Take the ’A’ Train”; on the Irving Berlin, Ethel Waters’s unforgettable “Heat Wave” and Fred Astaire’s seductive “Change Partners.” Listen to any one of these discs, and you may want the rest and then grow impatient for future installments.