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

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 Tonndorf and based on a simplified electro-acoustic model describes the phenomenon removal open earcanal high-pass filter due to perfect or partial occlusion. However, this has not been clearly defined several ambiguities remain. Revisiting model, second order for volume velocity transferred between wall eardrum highlighted. This remains but vanishes In latter case, from cavity middle ear through drastically increases, which explains predominance occluded outer pathway hearing bone-conduction at frequencies.