In The 21st-Century Voice: Contemporary and Traditional Extra-Normal Voice, Michael Edward Edgerton considers contemporary vocal techniques within an acoustic and anatomical framework. Throughout, he proposes new directions for vocal exploration. Much more than a historical treatise on 20th-century masterworks or vocal science, The 21st-Century Voice explores experimental methods of sound production, offering a systematic series of approaches and methods for assessing, engaging, and, in some instances, overcoming the assumed limits of vocal singing.
Appearing a decade after the publication of the first edition, this second editiondraws on and advances our current understandings of voice production. Divided into four parts--air flow, source, resonance/articulation, and heightened potentials--Edgerton considers crucial matters affecting vocal production, such as Registral challengesFiltering Airflow modificationCombinatorial, multiphonic principlesExtreme voice possibilitiesMultidimensional vocal issues