Barry Singing with Himself

So far, my favorite thing to listen to has been when Barry Manilow sings with his own self. So far I have come across three examples of this: The current way he is playing Mandy/Could it be Magic with his youthful self as he appeared on the Dick Clark show many years ago, and on two of his songs: One Voice and Nevertheless. I've listened to one particular section of his rendition of Nevertheless countless times, trying to confirm that's actually his voice singing the low part. I just find it hard to believe that his voice can actually go this low, unless maybe it's being aided by some sort of machine. It says in the liner notes, All Vocals: Barry Manilow but he has been known to pretend to tap dance and to pretend to play clarinet and saxophone, so maybe he is just pretending to sing that low part. It's just so low! Is that really him singing?