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When you speak, sound reaches your inner ear through the air and through vibrations conducted through the bones and tissues of your head. A recording mainly gives you the air-conducted part, so your voice can sound higher or thinner than the version you are used to hearing.

Reinfeldt et al., Journal of the Acoustical Society of America (2010)

ScienceMind

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The effect comes from bone conduction: when you speak, your skull vibrates, and those vibrations carry sound straight to the inner ear. This route favours lower frequencies, so your own voice sounds fuller and deeper to you than it does to anyone else. A 2010 study by Swedish researchers led by Sabine Reinfeldt, published in the Journal of the Acoustical Society of America, measured how much each route contributes as people pronounce different sounds. The same principle is used in bone-conduction hearing aids and headphones, which send sound through the skull instead of the ear canal.

Türkçe oku
Konuşurken kendi sesin iç kulağına hem havadan hem de kafatasındaki kemik ve dokuların ilettiği titreşimlerle ulaşır. Kayıt ise büyük ölçüde yalnızca havadan iletilen sesi verir; bu yüzden sesin alıştığından daha ince ya da tiz gelebilir.

Bunun nedeni kemik iletimidir: Konuşurken kafatasın titrer ve bu titreşimler sesi doğrudan iç kulağa taşır. Bu yol pes sesleri daha iyi iletir; bu yüzden kendi sesin sana, başkalarının duyduğundan daha dolgun ve daha kalın gelir. Sabine Reinfeldt'in yönettiği İsveçli bir ekibin 2010'da Journal of the Acoustical Society of America'da yayımladığı çalışma, insanlar farklı sesler çıkarırken bu iki yolun her birinin ne kadar katkı yaptığını ölçtü. Aynı ilke kemik iletimli işitme cihazlarında ve kulaklıklarda da kullanılır: Bunlar sesi kulak kanalından değil, kafatası üzerinden iletir.

Sources and further reading

Background reading: Bone conduction
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