Ethan Johns, one of the four producers on Paul McCartney's upcoming album, shed some light on the sessions for a new song, called, "Hosannah." Johns, who's the son of producer-engineer Glyn Johns -- best known for his work with the Beatles, the Rolling Stones, and the Who -- has his own roll call of credits including Rufus Wainwright, Kaiser Chiefs, Ryan Adams, and Kings Of Leon -- which is where McCartney first heard his work.

Johns explained the process for the four tracks he recorded with the former Beatle at George Martin's AIR Studios in London: "It was very low-key. (The idea was), 'Let's just go and hang out for a few days, play some music, have a bit of fun and see what we come up with. The first day we had was remarkable. He walked in with this incredible song, we threw up a couple of microphones and within four hours, we had this great track. I think we did an edit between the first two takes. It had an incredible feel -- a really evocative piece of music, a very interesting lyric, and the performance was great. Then we started to experiment with it, and I put a bunch of psychedelic strangeness on it. You have fun. 'Oh, try this! Do that!' It's just very inspiring to be around."

He went on to talk about McCartney's excitement at collaboration: "The first thing he said was, 'What do you feel like doing? I could have said, 'Let's spend the day making percussion loops with drum machines,' and he would have been, 'Great! Let's do that!' I don't think he ever said 'No,' which is kind of the mark of who he is as an artist, really. He's always up for trying something new."