Willie Nelson seems willing to record with just about anyone at the drop of a cowboy hat or a country beat. His recording partners include Waylon Jennings, Ray Price, his sister Ramona, Danny Davis and the Nashville Brass, Emmylou Harris and, most recently, Webb Pierce and Roger Miller.

The Pierce collaboration is perhaps the easiest to understand: Pierce's high-pitched, vibratoed voice -- along with Hank Snow's -- dominated country music during the early '50s, when the Louisiana honky-tonker had a string of 21 straight No. 1 hits. Pierce's honest, top-of-his-range delivery was a great influence on Nelson. It's eerily delightful to hear the two effortlessly trading verses and harmonizing on "In the Jailhouse Now," a sterling collection of Pierce standards.

Both singers tend to wrap themselves around lyrics, investing them with raucous energy or tremulous passion. Most of the songs here are classics, from the guilty quivers of "Wondering" and the chug-along joy of the title cut to the flip sides of falling in and out of love ("Slowly", "Let Me Be the First to Know" and "You're Not Mine Anymore"). Best of all are "There Stands the Glass," which became a national barroom anthem and a model for saloon confessionals, and "Backstreet Affair," whose sinewy melody propels classic hurtin' lyrics. It's a poignant exploration of the no-man's land between separation and redemption.

What makes this album delightful is its standard honky-tonk instrumentation: Strings mean Johnny Gimble's fiddle, and there's some outstanding crying pedal steel from Jimmy Day. Chips Moman's sensitive production is uncluttered, and the instrumental support throughout is understated and straightahead. Pierce is all but retired now, but Nelson has performed a valuable service with this celebration and renewal.

"Old Friends" teams Nelson with another major country figure, Roger Miller. But it's really a case of Roger or (mostly) Willie singing some of Roger's better known songs; the only duet is Miller and Ray Price singing the title cut. Miller's songs are a bit poppish and calculatingly sentimental, languid melodies encasing little slices of life.

Among the fine songs given average renderings are "Husbands and Wives," "When a House Is Not a Home," "When Two Worlds Collide" and "Invitation to the Blues," a 1958 hit for Ray Price. Where the Pierce album seems a labor of appreciation, the Miller album comes across as an unrealized flash of inspiration.

ON RECORD, ON STAGE

THE ALBUMS

WILLIE NELSON AND WEBB PIERCE: "In the Jailhouse Now" (Columbia PC38095); WILLIE NELSON AND ROGER MILLER: "Old Friends" (PC38013).

THE CONCERT WILLIE NELSON: Monday at 7:30 at Merriweather Post Pavilion.