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allmusic.com lists the following "styles" for Neil Diamond: [rquoter] Adult Contemporary AM Pop Contemporary Pop/Rock Soft Rock Singer/Songwriter [/rquoter]
Neil Diamond is a hit machine with the heart of a rock-and-roller. Unfortunately, he's trapped in a prison of gentle grooves.
Take in the last half of this -- see around 1:50 on -- and you'll see a great black metal cover that's never been made. <iframe width="420" height="315" src="https://www.youtube.com/embed/RQwqQwD6OOw" frameborder="0" allowfullscreen></iframe> Dude was very weird. Check out the band Super Diamond live sometime if you want to have a blast.
If I had to pick one genre that's not too specific and not too all-encompassing I would just say soft rock.
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