Writing a report on audiometry

[vabamyyr]

Im writing a report on audiometry and i don't understand what is the difference between ear bone sound conductivity and ear air sound conductivity. The methods they use to determine those parameters are so alike to me that it makes me wonder, what is the difference?

 

[Ouabache]

I am familiar with acoustics & the ear but not audiometry specifically. My thoughts are; there's a different propagation of sound reaching the sensory auditory cells through air (i.e. sound pressure wave vibrates the tympanic membrane, pressure signal couples to inner ear etc..), versus through bone in your head (denser material, causing different propagation behavior with a phase (time) difference reaching the cells, compared to air). You could even calculate the time it takes to reach the auditory cells in air-fluid compared to bone-fluid using basic acoustic physics (I leave that an exercise for the reader).