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Old 02-04-2008, 04:16 PM
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Re: Aural Moon Shows

Quote:
Originally Posted by VAXman View Post
OK. Just interjecting a bit on the technical.

We get a 32Kbps stereo stream. That is not high quality by ANY stretch of the imagination. This 32Kbps can, at max, sample at 22KHz (realistically, that's pretty poor quantization at that rate too). Being that this is a stereo feed, that sampling is safely half that for each channel or 11KHz. Nyquist-Shannon sampling theorem says that the maximum frequency that can be produced is 1/2 the sample rate. So, this puts the top end around 6KHz. Not great quality? Consider that the high C (key 88 on the piano) is ~4200Hz (middle C is 262Hz, so you can figure it exactly for 4 octaves higher) the frequency spectum we get isn't very good. I'll spare you the Fourier analysis of the distortion that this presents.

That said, I live close enough that I can get Gags off of the FM airwaves. The FCC's FM frequency allocations at ±100KHz permit about 15KHz as the maximum upper frequency (again, I'll spare you the math of the Fourier integral). This is CONSIDERABLY better than we get from the Real stream. If Gags will continue, it was my plan to erect a highly selective, high gain antenna and get the show off of the FM airwaves and encode it in a higher quality MP3 stream to send to the AM server. This would also get rid of the FM preemphasis which now gives Tom's show its bassy boomy sound.
you'd do that during all your copious free-time, Vax?

/hug
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