In the second episode of Toe-to-Toe with Ingo, voice scientist Dr. Ingo Titze is joined by voice pedagogues Kenneth Bozeman and Ian Howell for a candid conversation on perception versus acoustics—the often-surprising relationship between what we hear and what the voice is actually doing.

Together they examine how measurable acoustic events and subjective perceptual experiences sometimes align and sometimes diverge. The discussion explores why we hear a fundamental frequency even when only higher harmonics are present, why scientists speak of “pitch extraction,” why low-frequency vocalizations are perceived as rougher than high-frequency ones, and how pedagogical language around qualities like “buzziness” and vocal fry can blur the line between perception and mechanism.

The conversation also considers why sound pressure level does not always correspond to perceived loudness, how sounds that are acoustically weak may be perceptually strong—and vice versa—and what this means for voice training. Along the way, the group asks whether the linear, non-interactive source-filter model remains sufficient, or whether non-linear interactions must be built in from the start.

True to the spirit of the series, this is a thoughtful, rigorous exchange among scientists and teachers who are willing to challenge ideas, disagree respectfully, and follow the evidence wherever it leads.