“LET’S catch the fire AND SEE WHAT WE’VE GOT,” Robert Plant said about why he and Alison Krauss went back into the studio to record their new album, Raise the Roof, the follow-up to 2007’s six-time Grammy-winning album Raising Sand. With their combined talents and diverse tastes, the cliché about the odd coupling of bluegrass princess Krauss and rock god Plant doesn’t apply. Along with their first album and tour, this reunion, recorded prior to the pandemic (with a 2022 tour to follow), is a testimony to their mutual respect for a wide spectrum of music—country, soul, folk, and blues. Their collaboration was, once again, produced by T Bone Burnett, who played guitar, contributed song ideas, and assembled the musicians. Here, in two separate phone calls conducted by Lisa Robinson—Plant…