Geoffrey S. Mendelson wrote:
Commander Col. Klink wrote:
http://reviews.cnet.com/2300-33_7-10...s=0&o=10001201

HD radio was supposed to be the next great thing in "free" radio,
offering clear, digital "CD quality sound" and more listening choices.

It did. It just did it when no one cared.

What killed HD radio was the application of digital satellite TV technology
to home audio. Someone realized that you could take a "song" and make
a computer file out of it that contained the same data as a CD image in
one tenth the space.
[...]



That was definitely a factor, but "HD radio" was not only doomed
from the start, it was such a serious blunder that it may well lead
to the death of thousands of radio stations and the permanent
stunting of the industry itself.

There is nothing wrong with the concept of digital radio.

Using modern firmware-upgradeable codecs, orthogonal FDM
transmission, and a network of community transmitters in a dedicated
digital band, great things could have been done:

1. In every community, all signals would have been full-quieting
with no noise or multipath distortion. There would have been no more
disparity in signal or noise levels between 50-kW powerhouses and
250-Watt locals or 10-Watt student stations -- all would have had
perfect, full-quieting signals within the community's coverage area.

2. There would have been no more need for any licensees to sign off
or go to absurdly low power at night as obtains presently among AM
stations. And former AM stations would no longer suffer from
crippling skywave interference at night.

3. Depending on how much spectrum was allocated and the ratio of
talk to music programming (with their different bit rates), at least
four to eight times as many stations could have been allocated to
each community as now exist, leaving open the possibility of free
and independent public access and non-profit "free radio" style
programming, greatly expanding listening choices (and points of view
in news programming) for everyone.

4. As stations migrated to the new band, _even more_ channels would
become open on the existing AM and FM bands, making them more
listenable and viable again and allowing even _more_ space for
non-profits and those who want to broadcast for the love of it
instead of just for monetary gain.

Digital community-transmitter-based radio in a dedicated digital
band thus could have been a tremendous success and a revolutionary
improvement.

But we didn't get real digital radio.

Instead we got IBOC (In-Band On-Channel, now deceptively labeled "HD
radio"), a technical turkey which delivers almost none of the
benefits above and increases interference to boot.

Why did this happen?

Because the money-men didn't _want_ the benefits of item (1) above.
They already owned the 50-kW powerhouses. They didn't want the
10-Watt student station to suddenly have an equal signal to theirs.
They didn't want the mono AM daytimer to suddenly have 20-kHz
digital stereo with no audible noise and be on 24 hours a day as in
item (2).

And the money-men didn't _want_ dozens of new independent channels
to be available to listeners as in item (3) above.

So they chose IBOC, where the digital signal piggybacks on top of
the existing analogue signal, right on the same frequency. IBOC
gives distinctly inferior results. IBOC causes significant
interference. IBOC on AM is unlistenable and very nearly useless.

But IBOC gave the money-men the one thing they wanted most of all:
It preserves the inferiority of the smaller broadcasters. In fact,
amid a sea of IBOC hash from the big boys, it _accentuates_ their
inferiority.

The end result of this shortsightedness will be bankruptcy for many
stations, fewer and poorer choices for the listeners as
conglomerates gobble up the remains, and a huge migration away from
AM and FM broadcasts and to audio delivery via satellite and the
Internet.


With all good wishes,



Kevin Alfred Strom.
--
http://kevinalfredstrom.com/