Katy Perry recently brought her huge California Dreams tour to the UK, and while she was here we caught up with drummer Adam Marcello.
Marcello is also musical director for the show, so in a rare couple of minutes off we grabbed him backstage and asked just what MD-ing for such a huge gig involves.
And you can see a clip of Adam in action (rocking his illuminated Shine Drums kit) during one of Katy's UK dates from earlier this year below.
For more video lessons, kit tours and interviews visit our YouTube channel.
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