On the removal of the open earcanal high-pass filter effect due to its occlusion: A bone-conduction occlusion effect theory

Auteurs

Kévin Carillo, ÉTSFollow
Olivier Doutres, ÉTSFollow
Franck Sgard, IRSSTFollow

Type de document

Études primaires

Année de publication

2021

Langue

Anglais

Titre de la revue

Acta Acustica

Résumé

The occlusion effect is commonly experienced by in-ear device wearers as an increased loudness sensation of bone-conducted low frequency sounds. A widespread theory proposed by Tonndorf and based on a simplified electro-acoustic model describes the phenomenon as the removal of the open earcanal high-pass filter effect due to a perfect or partial occlusion. However, this filter has not been clearly defined and several ambiguities remain. Revisiting the model, a second order high-pass filter effect for the volume velocity transferred between the earcanal wall and the eardrum is highlighted. This filter remains for partial occlusion but vanishes for perfect occlusion. In the latter case, the volume velocity transferred from the earcanal cavity to the middle ear through the eardrum drastically increases, which explains the predominance of the occluded outer ear pathway on the hearing by bone-conduction at low frequencies.

Mots-clés

Protection de l'ouïe, Hearing protection, Évaluation du confort, Comfort assessment, Propagation du son, Sound propagation, Oreille, Ear

Numéro de projet IRSST

n/a

Citation recommandée

Carillo, K., Doutres, O. et Sgard, F. (2021). On the removal of the open earcanal high-pass filter effect due to its occlusion: A bone-conduction occlusion effect theory. Acta Acustica, 5, article 36. https://doi.org/10.1051/aacus/2021029