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Why does FM sound better than AM?

(www.johndcook.com)
259 points zdw | 2 comments | 13 Oct 24 22:32 UTC | HN request time: 0.382s | source
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matrix2003 ◴[14 Oct 24 00:15 UTC] No.41832921[source]▶
Someone gave me an analogy some time ago that made a lot of sense.

If you shine a flashlight through a tree blowing in the wind and vary the brightness to convey information, the signal can get distorted pretty easily.

However, if you have a constant brightness source and vary the color, it’s a lot easier to figure out what the source is trying to convey.

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reader9274 ◴[14 Oct 24 00:34 UTC] No.41833031[source]▶
I always shy away from analogies because more often than not they give the wrong "feel" for a concept. But this is one of those rare exceptions.
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Filligree ◴[14 Oct 24 00:40 UTC] No.41833068[source]▶
It's not an analogy. This is precisely how it works.
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khazhoux ◴[14 Oct 24 01:00 UTC] No.41833163[source]▶
Unless your car radio consists of a flashlight and a tree, this is an analogy.
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1. viraptor ◴[14 Oct 24 01:06 UTC] No.41833199[source]▶
Well... It kind of does. The source of the radio station is a kind of flashlight, just on a different frequency. The tree is still a tree (and all the other objects)
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2. cloudwalk9 ◴[14 Oct 24 01:16 UTC] No.41833257[source]▶
More accurately a giant lightbulb, but emitting at 102.7 MHz (my favorite local radio station) rather than ~450 THz (my favorite color).

Put visible light over a really long waveguide and modulate the colors, you invented fiber optic telecommunication.