Re: Audio quality degradation over FM transmission

Charlie Edmondson wrote:
> Nope, the MP3 player doesn't have that quality. The reason there are
> MP3s is because of compression, they eliminate some of the 'unneeded'
> data that is stored on the CD so that it will take up less space. This
> compression means that there is more noise and less dynamic range in an
> MP3 than the original. You also loose some of the highs.

I know that MP3 is lossy. All I am asking is if the audio input can
*physically* (due to transmission) match the audio heard over an FM
receiver exactly. Just assume that you have the highest quality CD
source media, CD player, FM transmitter, Antenna, FM receiver, and
Speakers -- and all that is left to degrade the signal is the
modulation of the input over the FM channel -- will the input match the
output??? This is what I want to know. I mean, the act of taking a
100% clean CD audio input -- piping it over FM (with no constraints but
the theoretical math involved in modulating the signal over say 108
MHz) -- will it end up 100% clean on the other side? I don't care
about any other factors. Mathematically, does the transmission of CD
audio input via FM have the effective output of about 256 Kbps MP3
lossy audio on the receiving end? Is it a degrading function (forget
the very low and very high frequencies)?

And if not, what is the theoretical maximum source input before you
start incurring loss on output? Obviously one could not send audio
sampled at 20 Ghz (insane) and get all that information over to the
receiver -- since 20 Ghz of information can not fit into that 108 Mhz
frequency band. I synnonomize this with mapping a much larger data set
onto a smaller data set (like an MP3 encoding). With two CD recordings
in a studio done at the same time using slightly different audo
equipment, it is mathematically possible for these two differing audio
samples to end up as an identical MP3 file in the end -- even though
there are subtleties in the original source audio, right? Would the
same be true of FM transmission of two similar sources? If not, then
you have a widening transformation of the original vector space.
Otherwise, it is a narrowing transformation resulting in loss of input
during mappings. Wow, I must have reworded this about 50 times
now...lol Forgive my naivety! I know I must be confusing some of you,
because I am confusing myself now...

Kristian Hermansen

.

Relevant Pages

  • Jon Ds 2 audio clips for our esteemed perusal
    ... This is in response to a thread that Jon started on December 18 titled "2 audio clips for your esteemed perusal" I finally got around to playing with the unprocessed mp3 a little. ... can make things sound thin and distant, but compression and limiting can ...
    (rec.music.makers.guitar.jazz)
  • Re: Codecs/WAV/WMM
    ... The mp3 audio file is good. ... ACM Microsoft IMA ADPCM CODEC 0011 imaadp32.acm 6.0.6000.16386 ... ICM Microsoft Video 1 MSVC msvidc32.dll 6.0.6001.18000 ...
    (microsoft.public.windows.vista.music_pictures_video)
  • Re: Help!!!
    ... can no longer handle so many audio tracks at the same time. ... Get a mp3 recorder like music match to make mp3 files. ... Buy a dvd burner. ...
    (comp.music.midi)
  • Re: Codecs/WAV/WMM
    ... Originally ripped in WMP, too ... I didn’t know if WMP shares codecs with WMM and /or DVDmaker ... The mp3 audio file is good. ...
    (microsoft.public.windows.vista.music_pictures_video)
  • RE: Converting 78 rpm vinyl discs to play via Windows Media Player
    ... sound coming into my computer had been connected to the SMP3P system. ... Settings that I put in to be able to copy from vinyl via WAV to MP3 9.7.09 ... I knew that the sound from the turntable was getting into the computer ... Under Audio Recording Options – select HD Audio Rear Input: ...
    (microsoft.public.windowsmedia.player)
Quantcast