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Cool article about HD Radio

Posted: Mon Aug 01, 2011 6:10 pm
by NECRAT
File this one in the "how it works" catagory.

http://www.hd-radio-home.com/hd-radio-technology.html

Thanks to Scott Fybush for pointing this one out.

Re: Cool article about HD Radio

Posted: Tue Aug 02, 2011 12:04 am
by Shane
Beg to differ with this statement from the article: "Of course, the digital signal will sound better, but the analog radio won't sound any worse."

I know, beating a dead horse that's already left the barn (how's that for a mixed metaphor?) but since it was newly resurrected I figured SOMEone needed to beat it back to death.

Re: Cool article about HD Radio

Posted: Mon Aug 08, 2011 8:50 pm
by K9EZ
You should have heard the hd2s Doc and had running in the early days without processing. It kicked ass! Then processing got put in the way......

Sent from my SPH-D700 using Tapatalk

Re: Cool article about HD Radio

Posted: Wed Aug 10, 2011 11:33 pm
by Shane
Dang processing and rules and stuff. Would have liked to have heard that.

Probably should have pointed out that I think it was the second part of the statement I disagreed with. ("..analog..won't sound any worse." True for FM; not true for AM.)

Re: Cool article about HD Radio

Posted: Thu Aug 11, 2011 9:18 pm
by NECRAT
Shane wrote:Dang processing and rules and stuff. Would have liked to have heard that.

Probably should have pointed out that I think it was the second part of the statement I disagreed with. ("..analog..won't sound any worse." True for FM; not true for AM.)
Grey Area city.

I have heard some excellent sounding analog AMs, and some horrible sounding ones. Same goes with digital AMs. (VERY VERY few HD AMs I have listened to sound good. There must be a "secret" to not make it sound so "fake", that most engineers don't know about.
Also goes with analog and digital FMs. Heard some great sounding Analog FMs (WSPK, WHYN), some great sounding digital FMs (WHJY, WHYN) and some truly horrible sounding analog FMs (names being withheld) and horrible sounding digital FMs (see horrible analog FMs)

Re: Cool article about HD Radio

Posted: Fri Aug 12, 2011 9:51 am
by Deep Thought
It is easy to screw up the processing (and despite some claims to the contrary, you need processing to maintain average loudness and combat the high levels of background noise in cars), but AM IBOC is a universal disaster. The analog bandwidth limits and sideband noise degrades the analog signal in an ironic way: On a good radio (one made before 2.3 KHz became the design target) there is an objectionable amount of self-interference hiss which is demodulated and mixed into the audio. I was surprised just how prevalent it is even on a 25 year old clock radio. A "table" radio from the 1960's was even worse, but it also has about a 10 KHz audio passband. One I tested from the 1950s was unusable on it's "hi-fi" setting, which sounded excellent prior to IBOC's adoption. If there is a third or fourth-adjacent running IBOC the noise is even worse.

I still say that if AM is as dead as the pundits want us to think it is, there is no reason not to run full digital mode at full power, which limits the IBOC bandwidth and excessive sideband noise and interference and produces superior coverage results.

Re: Cool article about HD Radio

Posted: Sat Aug 13, 2011 12:52 am
by NECRAT
Deep Thought wrote: I still say that if AM is as dead as the pundits want us to think it is, .
Sorry to derail the thread, but who the hell thinks AM is dead?? (And yes, I know you're not the one saying this...)

If AM is dead, why are there AM stations in the top 5 ratings slots in so many markets?

Those people must have no clue about radio in reality...

Re: Cool article about HD Radio

Posted: Sat Aug 13, 2011 10:17 am
by Shane
AM is not dead. But we're trying real hard to kill it. I happen to be employed by one of the larger groups and which is probably the only larger group that has more AM signals than FM. So it's possible to still make a living being an AM station, at least.

The larger markets prove all the time that AM signals can still lead the market, especially in revenue. But there's a new development you all have seen which may spell the eventual end or at least arrival at half-life.

Successful news and talk stations have begun migrating to FM at an alarming rate. Alarming, perhaps, to those who like music choices on FM as for every one that migrates there is one less music FM choice.

The largest example of this migration is WTOP, which did fairly well as a signal-compromised 50kW news station at the 'TOP of the dial, but as an FM has become the highest billing single station in the U.S. as well as the top-rated station (AQH share) in its market, a feat probably not possible with its AM signal, 50kW or not.

So while AM's strongest format for revenue migrates to FM, we're killing off the rest of the tenants with IBAC. Maybe that'll speed up the demise, which may be a good thing toward getting closer to a digital-only band someday.

I'm not worried, just intrigued to see what the AM band looks like in another 20 years. There could be some very good uses for an all-digital AM band, not all of them involving direct service to the public if the FCC sees fit to allow it.

<thread derailment complete!>

Re: Cool article about HD Radio

Posted: Sat Aug 13, 2011 11:14 am
by w9wi
I've launched a new thread on the "AM is {not?}dead" subject over on "Everything Else", where it's not as far off-topic :)

http://www.broadcastengineering.info/vi ... =19&t=3152

Re: Cool article about HD Radio

Posted: Sat Aug 13, 2011 1:18 pm
by Deep Thought
NECRAT wrote:
Deep Thought wrote: I still say that if AM is as dead as the pundits want us to think it is, .
Sorry to derail the thread, but who the hell thinks AM is dead?? (And yes, I know you're not the one saying this...)

If AM is dead, why are there AM stations in the top 5 ratings slots in so many markets?

Those people must have no clue about radio in reality...
Read just about any trade publication (Inside Radio, Radio Journal, Radio World, etc.) and they act like being on AM is some kind of cancer, and IR in particular has their heads planted firmly in their behinds. I won't continue this here to avoid the thread hijack but it is very prevalent in the very places who should be standard bearers for all radio.