On Wed, 11 Jan 2012 09:00:45 -0800, SMS
wrote:

I would caution you against falling in with the likes of Mr. Farce who
has demonstrated his lack of knowledge about broadcasting in general and
digital radio in particular.

Disclosu I'll classify myself along with Mr Farce, as my knowledge
of broadcasting ended in about 1972. I know just enough to be
dangerous.

I was doing some Googling the codec and found this item for 2003.

"Last-minute change casts doubt on U.S. digital radio spec"
http://www.eetimes.com/electronics-news/4045254/Last-minute-change-casts-doubt-on-U-S-digital-radio-spec
The National Radio Standard Committee (NRSC) questioned the
audio quality of iBiquity's original low-bit-rate PAC codec
in May and then suspended its standards-setting process,
with committee members bluntly saying they did not consider
the audio quality of the proprietary 36-kbit/second codec
fit for prime time.

Oops. Well, that's been fixed, but the early history of the codec
selection is rather interesting.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 1/11/2012 9:26 AM, Jeff Liebermann wrote:

Oops. Well, that's been fixed, but the early history of the codec
selection is rather interesting.

You need to read a bit further in the article you quoted:

"Their concerns center mainly on digital AM broadcasts, where critics
point to questionable audio performance, sparse coverage and
interference with adjacent analog channels."

I don't think anyone here would argue that digital AM is a waste of time
and that there are valid concerns about it. Interference is a real
possibility on AM, though as we've seen even in ba.broadcast there's a
tendency for some people that are philosophically opposed to digital
radio to attribute _any_ AM interference to AM HD, even when the accused
AM station isn't even broadcasting in HD!

As I stated, there are valid reasons to be opposed to digital radio but
the quality of the audio on FM digital radio is not one of those reasons.

On Wed, 11 Jan 2012 09:35:18 -0800, sms88
wrote:

On 1/11/2012 9:26 AM, Jeff Liebermann wrote:

Oops. Well, that's been fixed, but the early history of the codec
selection is rather interesting.

You need to read a bit further in the article you quoted:

"Their concerns center mainly on digital AM broadcasts, where critics
point to questionable audio performance, sparse coverage and
interference with adjacent analog channels."

Note the word "mainly". There apparently were also concerns over FM
quality.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

"Their concerns center mainly on digital AM broadcasts, where critics
point to questionable audio performance, sparse coverage and
interference with adjacent analog channels."

Note the word "mainly". There apparently were also concerns over FM
quality.

Only by the diehard HD Haterz.

On 1/11/2012 10:35 AM, Jeff Liebermann wrote:
On Wed, 11 Jan 2012 09:35:18 -0800,
wrote:

On 1/11/2012 9:26 AM, Jeff Liebermann wrote:

Oops. Well, that's been fixed, but the early history of the codec
selection is rather interesting.

You need to read a bit further in the article you quoted:

"Their concerns center mainly on digital AM broadcasts, where critics
point to questionable audio performance, sparse coverage and
interference with adjacent analog channels."

Note the word "mainly". There apparently were also concerns over FM
quality.

Unlikely. It's just a weasel word inserted by the author. If there were
concerns about FM quality then they would have raised them. You can see
by the independent tests of audio quality that FM digital consistently
ranks much higher in quality than FM analog. Perhaps the concern on FM
was that they thought "near CD quality" wasn't enough and they wanted
better than CD quality.

On Jan 11, 7:09*am, sms88 wrote:
On 1/10/2012 9:29 PM, MotoFox wrote:

And it came to pass that Richard Evans delivered the following message
unto the people, saying~

Actually I'm not sure, but in the past there have been broadcasts in
foreign countries, at up to 320k, and never at any bit rate higher than
that. Also I thought the limit for mp2 was 320k, but I might be wrong
about that.

MP3 tops out at 320k. MP2 tops out at 384; sample rates, 32000-48000 Hz.. I
don't believe MP3 is used over the air, but it is widely used for Internet
audio streams.

http://en.wikipedia.org/wiki/MPEG-1_...nical_specific...

(Oh yeah, and MP3 can't claim to have won an Emmy....)

LOL.

In the real world of radio what matters in terms of audio quality is
what radio listeners perceive. There have been extensive tests comparing
perceived audio quality of the different digital sources.

The iBiquity codec is based upon the AAC+ (HE-AAC) codec. "Scientific
testing by the European Broadcasting Union has indicated that HE-AAC at
48 kbit/s was ranked as "Excellent" quality using the *MUSHRA scale.[8]
MP3 in the same testing received a score less than half that of HE-AAC
and was ranked "Poor" using the MUSHRA scale. Data from this testing
also indicated that some individuals confused 48 kbit/s encoded material
with an uncompressed original." Look at figure 9 at
http://www.ebu.ch/fr/technical/trev/trev_305-moser.pdf.

Also read
http://www.nrscstandards.org/Reports%20ref%20docs/iBiquity%20Gen%203%....
You can see where "near CD quality" came from in figure 3.2. As that
report shows, the big problem with analog radio, is in impaired
conditions. Unimpaired, some analog radio was only a bit below the
quality of digital. Impaired, digital fared far better than analog
because of the multipath on FM analog. Of course the big problem is that
in impaired conditions, at 10% power, it would be difficult to even
receive the HD signal. That's why it's so important for radio stations
to increase their digital power.

Where we need to move to is FM HD Radio in pure digital at higher power.
It's the best transition to digital (at least the best one that anyone
has come up with), that preserves the present FM band during the
transition. It's time for the FCC to set some dates.

The consumer electronics industry has made a huge commitment to digital
radio, as evidenced by this years CES. Now it's the broadcasters turn to
take advantage of the increased penetration of digital receivers, and
increase power levels. The stations that have not yet added digital
service need to get with the program as well.

A Noisy Car/Trunk driving on a Road is not exactly
the best environment to judge Audio 'quality' in.

IBOC will become accepted {Standard} when the
FCC Mandates that all new AM/FM Radios built
for the US Market are IBOC Compliant and have
Plug-N-Pay SAT Radio built-in.

~ RHF

"sms88" wrote in message
...


AM interference to AM HD, even when the accused
AM station isn't even broadcasting in HD!


How many times are you going to spew that crap? It was the OTHER adjacent
channel polluting my A's game.

Mark

On 1/11/2012 12:35 PM, sms88 wrote:
[...]

As I stated, there are valid reasons to be opposed to digital radio
but the quality of the audio on FM digital radio is not one of those
reasons.



You write in an Orwellian Newspeak in which IBOC becomes "digital
radio."

The truth is that IBOC is a pathetically poor excuse for digital
radio in the same sense that a plastic ring from a Crackerjack box
is a poor excuse for a precious gem. And that is the real issue here.

If we had real digital radio, and we don't, there would be no such
thing as "AM digital" or "FM digital." There would only be digital
radio -- in a dedicated band with all licensees having
full-quieting, and full-time, and full-fidelity signals with
bandwidth to spare.

That, of course, is exactly what the money men did _not_ want.

So they did everything in their power to prevent it.

They were selfish and criminal, to be sure. But worse, they were
stupid. Their IBOC system, designed to preserve the "superiority" of
the big stations owned by the money men by continuing and
accentuating the inferiority of the small stations' signals, is
pretty much a retarded turkey that few have heard of and that no one
wants. It rings a pathetic and hokey death knell for radio broadcasting.



With every good wish,



Kevin Alfred Strom.

On 1/11/2012 6:12 PM, Kevin Alfred Strom wrote:

The truth is that IBOC is a pathetically poor excuse for digital radio
in the same sense that a plastic ring from a Crackerjack box is a poor
excuse for a precious gem. And that is the real issue here.

IBOC is a temporary compromise. Eventually analog will be turned off and
HD Radio will be all digital.

You have to look at the big picture and recognize the practical
considerations in moving from analog to digital, including the business
considerations. We've seen how well creating a new digital band
worked--it didn't.

We'll have to live with analog and digital co-existing, and the problems
that causes, for at least another decade.

"SMS" wrote in message ...

On 1/11/2012 6:12 PM, Kevin Alfred Strom wrote:

The truth is that IBOC is a pathetically poor excuse for digital radio
in the same sense that a plastic ring from a Crackerjack box is a poor
excuse for a precious gem. And that is the real issue here.

IBOC is a temporary compromise. Eventually analog will be turned off and
HD Radio will be all digital.


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Ah, yes... yet another denial of service to rural users of the media, just
like HD(?*)TV has been. I guess if you don't live in a core city area, you
just don't count (sort of like if you're over 50).

* Quite a bit of supposed HDTV, isn't. Stations that have multiple channels
cannot use full bandwidth for their main channel. Most don't use 1080p,
opting for 720p with an additional channel or two. The ones with 5 side
channels can't even use 720p, and run mostly 480p, which is only marginally
"better" than good old NTSC analog (and you could still receive the analog
signal at a distance, which you cannot do with ATSC.)