One problem in the experience of teaching voice technique that needs to be addressed, is the vast misunderstanding and subsequent confusion caused by students and some teachers implying that Falsetto vocal mode and head voice are the same thing, they are not.
Falsetto is a vocal mode, characterized by cricoid tile, epiglottic funnel narrowing, vocal fold closure, wind escaping through the glottis and residing in the head voice. The popular vocal metaphor, "head voice" refers to a register. A place where high pitches are produced regardless if those notes are phonated in twang vocal mode, falsetto vocal mode or distortion. We modify vocal modes inside the head voice. Until the student of singing realizes that he/she can sing different modes in the head voice, they are condemned primitive belting, constriction and limited artistic range. Understanding vocal modes and when and where to deploy them, is one of the secret keys to truly amazing, high performance human phonations.
So let's clarify this confusion around falsetto vs. head voice once and for all.
This essay first published August 30, 2010 on The Modern Vocalist.com the Internet's #1 community for vocal professionals, voice health practitioners and pro-audio companies worldwide since November 2008.