Radio Stations, what is their source?


What format do Radio Stations use for a source? I have been told MP3, then I heard a DJ mention he downloaded a certain remix from the 'net that he played, leaving me to believe they do use MP3.
brianmgrarcom
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The only station I listen to plays pretty much everything and anything as far as format(classical music only) goes and that includes a fair amount of LP's- its nice to hear a little hiss and pop coming from the radio :) They also do this program once a day called Performance today where they get a live performance some where and air it- often it takes place in the studio.
FM is 50-15kHz. AM is around a telephone land line. Open E on a 4 string bass guitar is around 40Hz.

Unless you are a 16 yr old female, try a test tone CD, like the Rives Audio or equivalent, and see if you *really have anything going on above around 10-15kHz. It will really open your eyes(ears).