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But that high C on a piano isn't a pure 4khz tone. There is a lot going on there above and below 4khz. You can prove this to yourself by looking at it in a frequency analyzer, or by simply listening to a pure 4khz tone and observing that it sounds a lot different than a piano. This is also why the same note played on different instruments sounds different.

If you lop off everything above 8khz, things sound "muffled", like you've put a thin blanket over the speaker.

No need to believe me, try it yourself in Audacity or any music playing app with EQ controls.



Not only that, but stringed instruments have a lot of frequencies in the first millisecond, right at the attack, until the string settles into its harmonic oscillations. This is very noticeable on a spectrogram and gives each plucked/raked/bowed note its distinctive character.


It is, and it's the data that a lot of audio compression algorithms manage to lose or mangle.

A plucked string in FLAC vs something like 128 or 160kbit MP3 sounds radically different. The same is true of the initial hit of a cymbal - they're just wrong when compressed.


Yeah. And I'm not even sure why this is controversial.

We all know that JPEG is a really good format, but like all lossy formats it struggles with sharp pixel-perfect text. More generally, lossy data compression struggles with those sorts of razor-sharp details.

I don't know why some fight tooth and nail against this in the audio domain.

In practice, yeah, MP3 is usually good enough. An isolated plucked string or cymbal crash is not something you come across too often. And that's why MP3 fares so well in listening tests against uncompressed audio.

But if you really want a full fidelity experience it's not the ultimate choice, any more than a JPEG of the Sistine Chapel is a 1:1 substitute for the real thing.


> An isolated plucked string or cymbal crash is not something you come across too often.

It really depends on what you're listening to. If you're, say, a fan of high speed bluegrass, it's an awful lot of isolated plucked strings. :)


Key word "isolated".

The high-speed bluegrass I enjoy has so many string events, so close to each other (in time), that almost none of them are isolated.


People aren't fans of high speed bluegrass? :)

Yeah I was definitely simplifying in order to keep things under 50,000 words hahaha




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