Summary
This lecture is a general introduction to human hearing
The three domains of physics that contribute to electroacoustics have been shown (electrical, mechanical, acoustical)
The different energy transformations explained here are introduced as electroacoustic transductions
The efficiency of the components of the auditory system depends on the frequency, this has for effect a hearing sensitivity relative to frequency
Further reading : equal loudness curves
The equal loudness curves (see the following graph) are obtained by inverting the sensitivity curves of the ear (see for example the amplification curves) for different excitation levels
The graph shows the gain to be applied (in dB) to a signal of frequency
for the human ear to perceive the same sound intensity for each frequency.Put another way, for the ear to perceive every frequency in the audible spectrum at, for example, 45 phons and taking 4000 Hz (40 dB) as the reference frequency
this is the amplification applied to a selection of frequencies:
20 Hz: around 60 dB
50 Hz: around 45 dB
125 Hz: around 30 dB
315 Hz: around 15 dB
800 Hz: around 5 dB
3000 Hz: around 5 dB
5000 Hz: around 0 dB
12500 Hz: around 20 dB
Therefore, loudness measures a sensation, not an excitation.
