3 ms·
> You can see a lot of repetition in the vertical direction, but these are probably redundant resonances. They don’t add any more information, so we should only
by munificent 3y ago
> You can see a lot of repetition in the vertical direction, but these are probably redundant resonances. They don’t add any more information, so we should only look at the base frequencies.
In the context of audio, these are just called "overtones", and the "base frequency" is the "fundamental".
The amplitudes of the overtones are what give an instrument its characteristic timbre. It's what makes a flute sound different from, say, a sax, when they are both playing the same note.
https://en.wikipedia.org/wiki/Overtone https://en.wikipedia.org/wiki/Overtone
https://en.wikipedia.org/wiki/Fundamental_frequency https://en.wikipedia.org/wiki/Fundamental_frequency
- NeroVanbierv 3y agoI knew that I had the wrong word, but couldn't think of the correct one. Thanks!
- adrianmonk 3y agoYeah, these are probably square waves. They sound like it, and square waves are the easiest to generate.
- munificent 3y agoYes, they are. (A funny side effect of getting into making electronic music is that I have a much better ear for synthesis and timbre now.) You can actually see this on the spectrograms too. Square waves have only odd-numbered harmonics, so the frequencies should be like: fundamental fundamental * 3 fundamental * 5 fundamental * 7 etc. If you look at the first note on the first image, it looks like the fundamental is around 2,200Hz, the first (loud) overtone is around 6,600, next around 11,000, etc. (There are some much quieter overtones at even multiples too, because hardware isn't perfect.)