Originally Posted by big_news_1
Originally Posted by charliemax
Real quick... People "hear" from 20HZ to 20KHZ. FM stereo "compresses" the energy in the top octave or so, down to 10Khz. It gives the sound more "punch". AM stereo faithfully reproduces the last octave and the sound is more "open" and "airy". Guess which "sound" people prefer 99 times out of 100?
That was quite interesting. Why aren't stereo AM radios common? Would my aftermarket CD player have a stereo AM receiver?
You're really sending me back in my time machine.
Generally speaking, AM stereo isn't prevalent because of the usual. Dollars and regulation.
To transmit, the station has to upgrade equipment. Corporations buying AM stations are making money because they are doing it on the cheap.
AM stereo also had to fight the FCC. It was long and involved and i don't understand it all, but it had to do with transmission band and signal strength.
I have been out of audiophileland for 10 years now. I don't know if AM stereo is making a resurgence and would be included in what you guys call your head amp (it'* actually a pre-amp and tuner). Back in the 80s it was just a matter of a chip included in the circuitry.
I think Sony and Motorola made them. And that was the other killer. As usual, Sony wanted their proprietary standard, while manufacturers that licensed the Motorola circuitry wanted a different standard or two. So that meant the music providers would have to accomodate all of the different standards. Bad business.
If you want to know the irony of it all. A pre-80s analog receiver would by 10x easier to modify to AM Stereo than the 80s to today digital receivers.
BTW, I sold stereo equipment in college. 99 times out of 100, people buy the "sound" with "punch". Usually only musicians or people who go to a lot of live non-electrically amplified music buy the more balanced, open sound. ie The violin just doesn't sound right to them over the hot system.
You guys do the same "punch" thing with your subwoofers. There'* no way you can fit a 50hz wavelength in your trunks, it'* too long. I think it'* about 10-12 feet long. (A 20hz signal is like 25 feet long.) What happens is that it "folds" over or "doubles" and adds to the 100hz signal. You're not hearing the actual bass, but you are getting one mean PUNCH at about 100hz.
And that'* cool. The important thing is to enjoy the music and have fun