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Old May 29th 06, 09:56 PM posted to rec.radio.shortwave
Telamon
 
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Default IBOC - Redefining AM Radio Service As We Know It

In article ,
Jake Brodsky wrote:

Snip

Having vented my spleen, let me say this to all you folk who think that
nothing can sound better than AM: Get over it. The biggest problem with
MW and SW AM broadcasting is that we don't have a capture effect of any
sort. AM can not have such an effect. But digital modes can clean up
the act considerably. Sorry, Telemon, some bright folks on a few
industry committees will find a reasonable suite of digital standards
some day, and when they do, AM will go the way of morse code. It can't
happen soon enough in my not so humble opinion. You will never convince
me that digital artifacts are worse than heterodyne whistles and
opposite sideband artifacts from a station 10 kHz away.


Snip

There are two issues he
1. What is actually operating to the current DRM standards.
2. What can be engineered.

Regarding #1

I fail to see how replacing "heterodyne whistles" that I can normally
adjust my receiver to mitigate anyway and replace that with "digital
artifacts" as an improvement. In other words replacing one type of
noise with another. I rationally can not accept this trade of one type
of noise for another type of noise as "better."

The problem I have with DRM is that it currently is not an improvement
and just provides a different listening experience not better in
general.

They (the DRM consortium) claim the "possible" while providing the
"actual" like it is the same thing. This is a bait and switch tactic
and I'm not buying it.

Regarding #2

Can DRM be better than current analog? You bet it can!

Can you stuff more information into the same bandwidth? No!

So in order to offer "better" sound quality the signal will have to
occupy more bandwidth not the same. Compression algorithms trade an
increase in information rate for an amount of distortion or artifacts.
I don't see any research to change this trade where you can have your
cake and eat it too.

There is the theoretical rule that a numerical sized bandwidth can
support a numerical value of information rate. For a DRM signal to
"sound better" it would have to overcome this rule. Compression
algorithms can not violate this rule without other consequences such as
sound quality.

The result is that DRM will have to use larger bandwidth than the
current analog scheme to it to actually be "better." Where "better" is
defined as good sounding audio without the artifacts and manage this
with a weaker signal whether that weakness is due to propagation, the
transmitter using less power, or both.

If broadcasters and listeners want to accept fewer available channels
then this can be an eventuality but listeners must in addition accept
that broadcasters will have control over who can listen and that over
time broadcasters can change the rules.

*******************************

I take the long view. The long view is freedom of information, which is
a fundamental right in this country. If broadcasters are going to
implement a scheme where by they control who can receive the
information for whatever reason then we will have an information cast
system.

This debate is just starting and it will be an issue in every delivery
system be it Internet, AM/FM BCB or short wave. From the beginning to
now if you bought any kind of service from an ISP you got the whole
Internet. From the beginning until now if you bought a radio you got
the whole of all programming it was capable of receiving. This is going
to change in the future if we accept what the industries are pushing,
which is a subscription model in addition to the equipment cost.

The USA understands and accepts money for access to "premium" content
but there has to be a broader availability of the free content
guaranteed or we will lose a part of what we are as a nation.

--
Telamon
Ventura, California