Tony Visconti says 'Where Are We Now' is very different to the rest of David Bowie's new album.

The legendary singer marked his 66th birthday by releasing the track yesterday (08.01.13) and his long term collaborator and producer says the album, 'The Next Day', has a much more ''rock'' sound.

Tony told the BBC: ''I think it's a very reflective track for David. He certainly is looking back on his Berlin period and it evokes this feeling. It's very melancholy, I think. It's the only track on the album that goes this much inward for him.

''It's quite a rock album, the rest of the songs, so I thought to myself, 'Why is David coming out with this very slow, albeit beautiful, ballad, why is he doing this? He should come out with a bang.' But he is a master of his own life. I think this was a very smart move, linking the past with the future, and I think the next thing you hear from him is going to be quite different.''

Tony - who worked on-and-off with the 'Starman' hitmaker on the record - dismissed speculation about the singer's health, insisting he is in good form and enjoyed being back in the studio.

He added: ''David is extremely healthy, he's rosy-cheeked, he smiles a lot.

''During the recording he was smiling, he was so happy to be back in the studio. From the old days I recall that he was the loudest singer I've ever worked with. When he starts singing I'd have to back off, and go into another room and just leave him in front of a microphone, he still has that power in that chest and in his voice. We all know he had a health scare in 2003, 2004, but he's a very healthy man.

''I can assure you, I've been saying this for the past few years. I couldn't explain why I know that, but I worked with a very healthy and happy David Bowie in the studio.''

'The Next Day' is released in March.