There is no true optimal angle for playing mandolin. Many players are dynamic with the angle. In this video I mess around with the angle and produce different sounds accordingly. I like the perpendicular to the ground. Then like 30 up or down for picking indivdual notes in chords. And even higher for hitting the money notes. :) Angle is meaningless because it does not correlate to timing, or development of the player. But a mandolin is a very technical instrument because unlike a guitar that supports the body naturally, the smaller mandolin is a game of angles and attacks.

- Joe Gelb

http://www.twitter.com/josephgelb