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Why does FM sound better than AM?

(www.johndcook.com)
259 points zdw | 3 comments | 13 Oct 24 22:32 UTC | HN request time: 0.591s | source
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Optimal_Persona ◴[14 Oct 24 00:37 UTC] No.41833049[source]▶
Also the audio frequency bandwidth is narrower on AM, so fewer treble frequencies.

TBH I think music from up to the late '60s (especially if originally released in mono) sounds really good, or at least more "era-appropriate" on AM radio. I remember my grandparents tuning in to easy-listening AM stations as I grew up in the '70s and '80s, to my ear Tennessee Ernie Ford's "16 Tons" or a classic Phil Spector "Wall of Sound" production sounds more "right" coming through the AM bands.

And, in the age of cellphone speakers and compressed MP3/Bluetooth codecs - I'm not sure how much people actually care about audio quality.

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trq01758 ◴[14 Oct 24 07:25 UTC] No.41835084[source]▶
Those codecs got better with time. Also notebook and little portable speakers, while they are unable to physically reproduce low frequencies are getting better at emulating those. Somebody cares.

And here's (dunno if true as they write in the description - probably the very first stereo) studio turntable from 1958 playing a record from 1988 through Youtube's compression. I did have a lousy vinyl deck with so so speakers when growing up and this impresses me a lot: https://youtu.be/PRty-_eBEpg?si=GsrctxRbkvT3xRAV

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1. kaoD ◴[14 Oct 24 11:06 UTC] No.41836372[source]▶
What does "emulating low frequencies" mean?
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2. trq01758 ◴[14 Oct 24 12:28 UTC] No.41836881[source]▶
It may be impossible for a little speaker to produce any sound at some low frequency, so manufacturers use "virtual pitch" psychoacoustic phenomenon by introducing harmonics above that frequency. There is no low bass, but there will be added harmonics that will be perceived by the listeners as low bass: https://sound.stackexchange.com/questions/37755/how-do-psych... Here's also a project and some info from Asahi devs on Macbook audio: https://github.com/AsahiLinux/asahi-audio
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3. Johnythree ◴[14 Oct 24 13:42 UTC] No.41837448[source]▶
Is commonly known as "Bass Boost".

As the OP has said, it cannot give louder bass, but simulates the bass harmonics.