> > > In summary, what are the differences?
CD is 44.1kHz, 16 bit sampled UNCOMPRESSED (aka: WAV) digital audio
Sat audio is highly compressed (as much as 7:1)...HD radio is almost as bad...
MP3, Mpeg2 (which a lot of audio systems like Prophet, etc use) and anything else that uses compression is NOT CD audio...
> > > Is there anywhere I can compare services?:
> > > online streaming versus...
> > > HD versus...
> > > satellite...
> >
> HD is not CD quality. XM and Sirius are not CD quality.
> Frequency response doesn't tell the story. ANY digital
> compression scheme degrades the audio because it throws away
> detail which can't ever be recovered. Sometimes you'll hear
> it, sometimes you won't.
In a lot of compression schemes (especially MPEG2 with a 4.4:1 or worse compression), the low end suffers....play a CD and a MPEG2 or MP3 and switch back and forth in an A/B test...you will notice the difference..
> Many FM stations are still using digital studio-transmitter
> links which use compression.
Some are...MOST FMs realize you should be running UNCOMPRESSED STLs...
T1s are, so is the Harris Starlink....but the Moseley DSP series?? OH YEAH thats compressed and you can tell! Any ANALOG STL will be uncompressed of course.
> All satellite music networks use compression.
>
> Talk shows generally use an ISDN or Pots line codec for
> delivering the show to the network, and that involves
> compression. Then they upload to the affiliates again using
> compression.
>
> Many FM radio stations still install their music on hard
> drive utilizing compression.
Now that HDs costs a lot less, it makes more sense to use uncompressed WAV audio on the system......Prophet's original CFS Wizard was MPEG2 and the min compression was 4.4:1 IIRC....NEXGEN now allows you to use UNCOMPRESSED audio as well as MPEG2 or others...I had a talk show (LoveLines) on one station where it was recorded the night before...I had the system do it at 22:1 ratio!! Worked ok for voice...but music would SUCK!
> Most agency commercials are now delivered via mp3 files
> (compression again).
Which is totally stupid.......so much for quality!
> Bottom line... you may have the "frequency response", but
> you may end up with noticably degraded audio due to the
> multiple generations of compression.
>
> What are Jones, ABC, and Westwood One going to do when their
> affiliates take their compressed audio, which contains
> twice-compressed commercials, and broadcast in "HD Radio"
> and it sounds like poop? What will national accounts do
Analog already sounds that way!!! Its even worse since they go A->D->A->D->A->D->A by the time they get to the xmtr!! Each time you convert BACK to analog, you lose! then its back to digital where MORE is tossed away by compression (and we arent talking compression like audio processing...think ZIP files here instead
If it was straight digital and using sample convertors, it would not be as bad....but still!!!
> when their mp3 commercials run through the network and then
> the local HD Radio transmitter and sound even worse than the
> Sears radio commercials we hear today?
> Digital is no more than a feel-good buzz word.
AMEN!!! Unfortunately, the last analog hold out is giving in...AIRCRAFT radio is going digital...the last AM analog holdout in two way radio world....pity....
AM analog is known to be a good weak signal mode...which is needed in aircraft use...but digital?? there goes the neighborhood!
