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In '97 I bought a '96 Mustang and had an AM station on for some reason; maybe a Cubs game. I was shocked to hear stereo effects come out of the speakers, and th

In '97 I bought a '96 Mustang and had an AM station on for some reason; maybe a Cubs game. I was shocked to hear stereo effects come out of the speakers, and then I looked at the LED display on the radio and saw a little "headphone" icon. Sure enough, the stock Ford radio had AM stereo. Cool novelty, but in the end it was the same AM sound quality but with two channels. A worthy improvement though.

TedDoesntTalk 4y ago
> it was the same AM sound quality but with two channels This conflicts with the website. It says the sound quality of AM Stereo is as good as FM.
- Aloha 4y ago
  An AM channel can pass 12-13khz of audio an FM channel about 19khz, they sound dramatically different though because of different equalization curves. AM stereo sounds nearly as good as FM, while also feeling "richer".
  - Lio 4y ago
    It sounds like the marketing for AM Stereo focused on the wrong things. Really they should have stressed the range (so more station choice in more places) and the jump in fidelity rather than the stereo bit. Convenience over quality worked for VHS vs Betamax. It could have worked for AM Stereo too.
    - Aloha 4y ago
      Kinda, as I pointed out on a parallel thread, it failed for a variety of reasons. First thing is the early AM Stereo radios didnt sound very good, mostly because of the narrow IF (a heavy rolloff over 8khz), but there were other inherent issues with AM that it didnt attempt to immediately solve too, like poor quality noise blankers. Later on they intrigued the AMAX AM Stereo Radios did solve a bunch of quality issues with AM - 1) Wider IF (meaning more fidelity) 2) Much improved noise suppression 3) Other improvements improving platform stability (meaning preventing stereo center from shifting left-right. If failed because: 1) poor noise rejection of AM and naturally high noise on the AM band 2) changing programming on AM (aka the rise of talk radio) 3) delay in the FCC picking a single AM Stereo standard, they decided to "let the market chose" which means for like 6 years there were multiple mutually incompatible AM Stereo standards on the air, which reduced incentives by receiver manufacturers to introduce support.
- regular 4y ago
  I don't recall anyone ever claiming that it was truly comparable in fidelity to FM. In addition to bandwidth limitations, AM is still subject to way more interference than FM. Maybe in a perfect lab setting it could approach FM, but... yeah. ¯\_(ツ)_/¯

TedDoesntTalk 4y ago

> it was the same AM sound quality but with two channels This conflicts with the website. It says the sound quality of AM Stereo is as good as FM.

Aloha 4y ago
An AM channel can pass 12-13khz of audio an FM channel about 19khz, they sound dramatically different though because of different equalization curves. AM stereo sounds nearly as good as FM, while also feeling "richer".
- Lio 4y ago
  It sounds like the marketing for AM Stereo focused on the wrong things. Really they should have stressed the range (so more station choice in more places) and the jump in fidelity rather than the stereo bit. Convenience over quality worked for VHS vs Betamax. It could have worked for AM Stereo too.
  - Aloha 4y ago
    Kinda, as I pointed out on a parallel thread, it failed for a variety of reasons. First thing is the early AM Stereo radios didnt sound very good, mostly because of the narrow IF (a heavy rolloff over 8khz), but there were other inherent issues with AM that it didnt attempt to immediately solve too, like poor quality noise blankers. Later on they intrigued the AMAX AM Stereo Radios did solve a bunch of quality issues with AM - 1) Wider IF (meaning more fidelity) 2) Much improved noise suppression 3) Other improvements improving platform stability (meaning preventing stereo center from shifting left-right. If failed because: 1) poor noise rejection of AM and naturally high noise on the AM band 2) changing programming on AM (aka the rise of talk radio) 3) delay in the FCC picking a single AM Stereo standard, they decided to "let the market chose" which means for like 6 years there were multiple mutually incompatible AM Stereo standards on the air, which reduced incentives by receiver manufacturers to introduce support.
regular 4y ago
I don't recall anyone ever claiming that it was truly comparable in fidelity to FM. In addition to bandwidth limitations, AM is still subject to way more interference than FM. Maybe in a perfect lab setting it could approach FM, but... yeah. ¯\_(ツ)_/¯