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Why does FM sound better than AM?

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259 points zdw | 2 comments | 13 Oct 24 22:32 UTC | HN request time: 0.405s | source
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davekeck ◴[14 Oct 24 00:28 UTC] No.41832998[source]▶
I always assumed it was because FM station bandwidths (200kHz) are much wider than AM (10kHz). AM's 10 kHz chops off a lot of human-hearable frequencies.
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ndndjdjdn ◴[14 Oct 24 00:58 UTC] No.41833153[source]▶
AM doesn't use the frequency for modulation though so it shouldn't matter.
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t-3 ◴[14 Oct 24 01:27 UTC] No.41833331[source]▶
AM does use the frequency, it just doesn't need as much and uses it differently than FM. If it was all at a single frequency, there just be a single tone getting louder and softer.
replies(1): >>41833375 #
1. ndndjdjdn ◴[14 Oct 24 01:33 UTC] No.41833375[source]▶
Thanks. I just learned that doing a rabbit hole about sidebands! Still getting my head around it.
replies(1): >>41834791 #
2. YZF ◴[14 Oct 24 06:32 UTC] No.41834791[source]▶
Once you change the amplitude of a sine wave (modulate it) it's no longer a side wave. It spreads in the frequency domain. Take the fourier transform of that and you can see the frequency components.