5 ms·
Frequency is the repetition rate of the sound wave created by the instrument. Pitch is the perceptual (i.e., human auditory perception) correlate of frequency.
by sevagh 5y ago
Frequency is the repetition rate of the sound wave created by the instrument.
Pitch is the perceptual (i.e., human auditory perception) correlate of frequency. Pitch is what your brain/auditory system interprets that it hears from the sound wave at that frequency.
For a piano chord, there is likely the fundamental frequency (or f0, the lowest frequency), and its upper harmonics (integer multiples of the fundamental). That's why musical instruments (like the piano) sound richer than simple sine waves: their physical bodies create richer, more complex waveforms from the harmonics, giving it a unique timbre.
There are some subtle differences. For example, (very oversimplified), if you were made to listen to a waveform containing the frequencies of 60 Hz and 90 Hz, your auditory system would "hear" a pitch corresponding to a fundamental frequency of 30 Hz, since 60 Hz and 90 Hz are integer multiples of 30 Hz.
- criddell 5y agoIs the phenomenon you describe in your last paragraph the thing that makes a Shepard scale work? If one were to make a pitch classifier machine, would it always agree with the human ear?
- sevagh 5y agoI don't know much about the Shepard scale. Regarding a pitch classifier machine, typically algorithms for pitch classification/tracking/detection focus only on the fundamental frequency (or f0) of the input sound wave. So, _technically_ pitch and f0 are used interchangeably where they shouldn't be. I have yet to see a pitch classifier machine that tries to implement the special workings of the human auditory system.
- pvarangot 5y ago> There are some subtle differences. For example, (very oversimplified), if you were made to listen to a waveform containing the frequencies of 60 Hz and 90 Hz, your auditory system would "hear" a pitch corresponding to a fundamental frequency of 30 Hz, since 60 Hz and 90 Hz are integer multiples of 30 Hz. Eh, so if you add 60hz and 90hz you get a wave that repeats every 33ish milliseconds. You don't "hear a 30hz sine wave" that your brain is inventing, that's a very common misconception. You just hear a 30hz "thing" that is not a sine wave because there's a 30hz thing that is not a sine wave playing. Just try adding an actual 30hz sine wave to the 60+90 thing and you'll see it sounds very different to what you hear when you add those two sine waves. If you keep on adding waves spaced 30hz adding the 30hz or 15hz one wouldn't make much of a difference because what you are listening to is something very similar to a low pass filtered 30hz pulse wave.