When the two vocal cords differ in tension, mass, length, or stiffness, they go out of sync — vibrating at separate pitches simultaneously. This double sound is diplophonia, perceived as rough hoarseness.
Husky hoarseness arises from a gap; rough hoarseness arises from asymmetry. Any asymmetry between the two vocal cords — in how tightly they are stretched (tension), how heavy they are (mass), how long they are (length), or how flexible they are (stiffness) — will tend to cause them to vibrate out of sync. When that happens, two sound sources compete and we hear two pitches at once: diplophonia, perceived as roughness or a gravelly quality. Disorders often have both air leak and asymmetric vibration.
Asymmetric Tension
Faith’s voice fades at low pitch — one cord bows and flutters while the other holds firm. Uneven tension creates diplophonia.
Asymmetric Mass & Length
Norm’s hemorrhagic polyp creates rough hoarseness at low pitch, pitch breaks in mid-range, and split pitches up high — all from one lesion.
Asymmetric Stiffness
Sarah’s stripped cord is stiff; her supple cord is not. In mid-range they oscillate at different pitches. Paradoxically, full stiffness would sound clearer.
Asymmetric Length
Samantha’s two cords are different lengths after multiple emergency intubations — they cannot align and tend to vibrate at two separate pitches.
Asymmetric Summary
All four asymmetry types cause diplophonia. Hoarseness is a general term; huskiness and roughness are its two precise components.