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Comment by xenadu02 | Hacker News Reader

True but hearing is logarithmic in both volume and frequency domains. Double the power does not equate to anything near double the loudness. Similarly each doubling of frequency is only one octave higher. Hearing up to 80khz doesn't mean hearing 4x more than humans... 10 octaves for humans, 12 octaves for cats. In a musical sense it probably isn't noticeable.

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The extreme upper limit of human hearing is around 20khz, so cats really are hearing things that we don't, and for good reasons.

Sensitivity to different frequency ranges is more or less independent of anything else. Birds have heightened frequency response in the range they vocalize in, which helps them hear others if their species. Same for us; we vocalize at relatively low frequencies, so most of our hearing ability is focused on that range. There is also a range below which we don't hear: infrasound, which is utilized by elephants.

Logarithmic perception is certainly real, but the tuning of which frequency ranges an animal is more or less sensitive to is certainly species dependent.

As a comparison with removing the top two octaves from a cat's hearing, try removing the top two octaves from an audio file compared to your hearing range (lowpass at 5 kHz or less if you have hearing range loss, and/or resample to 10 kHz/ksps or less) and see if the results are musically noticeable. (At least for humans, the result is intelligible but heavily muffled, I can't speak for my pet cats though.)

That's fair... I'm just saying you shouldn't compare 20hz-20khz vs 20hz-80khz then decide cats can hear "three times" as much as humans. Two octaves is more than zero but a lot less than 3x.

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