There is a patch of specialized haircells, called papilla amphibiorum, in the inner ear capable of detecting deeper sounds.
ðɛɹ ɪz ɐ pˈætʃ ʌv spˈɛʃəlˌaɪzd hˈɛɹsɛlz, kˈɔːld pæpˈɪlə æmfˈɪbɪɹəm, ɪnðɪ ˈɪnɚɹ ˈɪɹ kˈeɪpəbəl ʌv dɪtˈɛktɪŋ dˈiːpɚ sˈaʊndz.