Here is another video of Tatu playing his melodica that is tuned to create a vibrato and a picture of the reed section. His work is exceptional and very thought out.
https://www.facebook.com/tatu.salmela/videos/10207118370756245/
https://www.facebook.com/photo.php?fbid=10206690498179698&set=p.10206690498179698&type=3&theater