[BC] dueling algorithms and audio quality

[Broadcast List USER]

Well, yes, and no.

There are some pretty good D to A converters.  Between oversampling,  
dither, digital reconstruction filters, they can be pretty good.

Yep, I am one of the many who don't like what CDs did to music.  No  
one had the vision to use high sample rate Delta Modulation.  Still,  
some of the Telarc and other recordings sampled at 180 kHz and above  
were stunning.  For the most part, you cannot get them now, but there  
are some very high quality digital recordings on the oddball web  
sites.  One of the not so good thins is that while the recordings are  
pretty darned good, the performances are not so stellar.

On the other hand, I agree with you.  For example, if you use a  
computer to compose a CD with a 20 kHz square wave on an audio CD,  
what do you get when you play it back through a CD player?  Well, it  
is a somewhat distorted (because of problems with the reconstruction  
filters) 20 kHz SINE wave.  The filter will rub off all the corners by  
removing the harmonics, though not perfectly.

High slew rate signals are screwed up by the anti-aliasing filters on  
the recording side too.

Then again, tape saturation, the non-linear problems with tape  
recording, and the NOISE, are not issues at all.

If we had a MUCH higher sample rate, things would have been just  
fine.  If we had that, the D to A would not be an issue, and the  
reconstruction filter would be trivial.

Then enemy of good enough is perfect.  In my opinion, 44.1 kHz 16 bit  
linear is just good enough for broadcast.  It isn't perfect, but for  
car listening it is more than enough.  For critical listening at home,  
maybe not, but we have the restrictions of the mediums (AM & FM).

--chip

On Oct 2, 2009, at 2:27 AM, broadcast-request at radiolists.net wrote:

> Message: 20
> From: "Dana  Puopolo" <dpuopolo at usa.net>
>
> Actually you are only partially right, Chip, because eventually  
> digital HAS to
> become part of the analog domain-and that's frequently where mucho  
> quality is
> lost.
>
> -D
>
>> Just keep it linear and digital is OK.
>>
>> --chip