> There should exist frequencies impossible to reach for anyone but post-pubescent men.... Of course that would make it teen-age verification at best. Yes and

> There should exist frequencies impossible to reach for anyone but post-pubescent men.... Of course that would make it teen-age verification at best. Yes and no. Like geology, the more you dig into audio, the more is uncovered and available. A child/teen with a deep voice has very unique perturbations that don't exist in other cohorts across feature sets. Adults may share some characteristics, but not at the levels found in specific age groups.