What do blues musicians talk about when they meet up socially?

Old records? Recording in Memphis? Animal sanctuaries in Aberdeenshire? Next time Paul Rodgers and Joe Bonamassa get together they can cover all three topics because Rodgers, whose voice fronted Free, Bad Company, his band with Jimmy Page, the Firm, and for a while after Freddie Mercury's death, Queen, has recently released an album of Memphis blues and soul classics, recorded with the house band in the studio where the legendary Willie Mitchell refined the signature Hi Records sound.

Rodgers and his wife,Cynthia have also, after being tipped off about its good work by Bonamassa, become patrons of the Willows animal sanctuary in Fraserburgh, with which, for people who live closer to the Pacific coastline than the Aberdeenshire fishing community, they seem remarkably well in tune.

It's the Royal Sessions, however, his homage to the music that fired him up as a teenager singing with bands in the North East of England, that Rodgers is on the line from California to discuss here.

"I can remember being at school and hearing Otis Redding for the first time and what an impact that made on me," says Rodgers, who hasn't lost his Middlesbrough brogue despite not having lived there for close on 50 years. "So for me to be going to Memphis to record an album is actually unbelievable."

It was Rodgers' producer Perry Margouleff who suggested working in Royal Studios, where Al Green, Ann Peebles, O.V. Wright, and Syl Johnson made their classic soul recordings under Willie Mitchell's assured guidance. Mitchell died in 2010 but his son Boo continues the family business and Royal remains a thriving recording studio where musicians can utilise vintage equipment, the Hi Records rhythm section, featuring brothers Charles and Leroy Hodges, and the atmosphere of the room.

"I don't think it's too fanciful to say that you can feel Willie Mitchell's spirit there," says Rodgers. "The air seems to radiate with a special atmosphere and the later the nights wore on, the more you'd feel it. Also, there are parts of the building that they don't use anymore and you can go up these creaky stairs away up to the top at the back and look down on the musicians working and really get a sense of what it must have been like in the 1970s."

Rodgers also found tangible artefacts including the master tape of Ann Peebles' I Can't Stand the Rain stored in the corridor between studio and control room. He almost caused a pile up with the house band who were following him when he stopped to gawp at this piece of soul history. Of course, these were the same musicians who played on Peebles' original and when Rodgers asked if he could add the song to the list, they readily agreed and even found the electric bongo that made the distinctive drum sound on Peebles' hit to add extra authenticity to Rodgers' version.

The Hodges brothers and their colleagues are such masters of their craft, says Rodgers, they can work up an arrangement and be ready to record a song almost at the snap of a finger.

"Some of the songs I'd performed before, like Born Under a Bad Sign, which we used to do with Free," he says. "But others, although I've known them since the days when my band the Road Runners used to go to the Purple Onion club in Middlesbrough after gigs and hear the DJ play them, I'd maybe only sung in my bedroom. And there's a difference between singing something to yourself or in the car and standing in front of a microphone with the band that made the record. So I'd gone in prepared and was I glad because I said 'Can we try I've Been Loving you Too Long?' and we got the key, the guys went into a quick huddle, we counted it in and, really, they took me to another place. The run through became the take you hear on the album."

Rodgers will be playing some of the songs from the Royal Sessions on the road with his own band this summer. His studio collaborators don't tour, alas, but he has had the thrill of playing with them in front of an audience during the album launch, for which they moved to the former home of Stax Records.

"That was a blast, too," says Rodgers who can remember what he was doing when the famous Stax Revue played Finsbury Park Astoria, round the corner from his first flat in London, in 1967 - sitting in the house, skint. "It must have been amazing to be part of that Memphis scene back then, with musicians like that. Every song we did, they nailed it immediately and that's great because you can run through a song 100 times and the 100th take might be perfect but it lacks energy. I like to go for one take that has the spirit, and I think we caught that with the Royal Sessions."

l The Royal Sessions is released on 429 Records.