[Harp-L] How much of the harmonica do you put in your mouth?

[Harping On]

Here is a video of Christelle Berthon demonstrating her embouchure while playing 'Yesterday'. Her top lip is covering most of the top cover plate of the harp and her bottom lip is rolled under the lower cover plate. It is a good way to get good tone as long as you are able to get a decent seal on the harp. So you have to play around with what feels comfortable with your physiology. 

Poor tone is acheived when your lips form a whistle shape on the harp.

https://youtu.be/RuH-Keoqca4?t=74