What Floats Your Note

It can be rather difficult to imagine how forces work upon the vocal chords in order to produce and change sound, so here is a visual to help you picture how pressure, tension, and push act on the vocal chords. Air pressure forces the folds to expand and contract while muscles along the outer edges use a combination of tension and push to abduct and adduct the folds.

(graphic from http://www.ncvs.org/ncvs/tutorials/voiceprod/tutorial/model.html)