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HD on WINS and WCBS AM

I have the misfortune of living in Metro Detroit, where AM IBOC adoption was (once) widespread due to Chrysler, Ford and GM all being based here.

As soon as the COVID-19 national emergency was declared, AM 950 WWJ and AM 1270 WXYT both turned off their digital noisemakers! (Entercom probably figured with far fewer commuters, there is little reason to compromise analog signal quality by allowing the IBOC exciter to remain on.)

Both stations' analog signals are once again broadcasting in full 10 kHZ bandwidth!!! :) WWJ's analog fidelity hasn't sounded this good in oh so many years! I was beginning to wonder if I'd ever see this day come to pass!

The problem is - thanks to the advent of IBOC digital broadcasting, most car manufacturers and many home receiver manufacturers have squeezed analog dynamic range reception capability from 10 kHz down to 5 kHz or even 3 kHz for units manufactured within the past decade! Why did they do this? Well, the usage of IBOC digital transmission on the AM band greatly increased the amount of noise across the band. By only allowing "narrow band" reception, unwanted interference from IBOC's sideband hash was mitigated. Other devices like set top, WiFi enabled cable boxes create plenty of interference, too, although constricting bandwidth doesn't do much to solve that issue.

On narrowband AM receivers, the analog audio of AM radio stations employing 10 kHz bandwidth sounds no better than stations employing 5 kHz bandwidth. To make matters worse, 10 kHz stations who use very LOUD processing (760 WJR, I'm looking your way) sound very distorted when listening on an AM receiver that is constricted to 5 kHz bandwidth or less.

IBOC transmission on the AM dial has only helped to accelerate AM radio's demise as a mainstream broadcast service. Almost no receivers used in the home can decode digital audio. What a brilliant idea - to add a TON of additional noise to an already high noise floor for folks attempting to tune in an AM station, in analog, inside the house. The herd mentality broadcasters who adopted this terribly unproductive technology have nothing but sagging ratings and sagging revenue to show for it.

And by the way, a properly processed 10 kHz analog AM station will *always* sound somewhat better than a decoded IBOC digital signal. No tinny artifacts and much richer bass and depth of sound! I will say the IBOC digital signal does a little bit better job concealing noise, but once you drive into a really "noisy" area (i.e. near high voltage power lines), the digital signal gets completely lost and reception reverts to analog anyway.

In Metro Detroit, I believe 910 WFDF and 1200 WCHB are the only two AM stations whose IBOC exciters are on. I will give both of these stations some credit; their analog fidelity actually sounds pretty good. The most recent generation(s) of IBOC technology doesn't seem to create nearly the same level of noise as the first couple generations, but unfortunately, the damage has already been done. Many listeners have left the AM band for good and won't be coming back. I realize multiple factors have contributed to this outcome; the sloppy implementation of IBOC on the AM band more than a decade ago was simply an act of adding fuel to a smoldering fire.

If the NAB were an honest organization that actually cared about engineering standards, instead of lobbying for IBOC on AM (so that Clear Channel and other companies with a stake in iBiquity could line their pockets), they would have instead invested all of that time & effort in lobbying the FCC to mandate improved manufacturing standards for AM radio receivers and to impose rules designed to limit AM band noise.

By the way, from a public acceptance standpoint, digital-only FM2/FM3 stations are a joke, too. They represent - excluding analog translator listenership - less than 1% of total FM listening. They have done next to nothing to reign in Sirius XM, whose subscription numbers keep growing each & every year (although I have a feeling 2020 might be the first year where that cycle is broken).
 
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Didn't the critical mass of technology leave HD radio behind years ago? It's impossible to deny that essentially all the growth has been with streaming, smartphones, apps, and now smart speakers at home.

Sure there has been a gradual increase of factory-installed car radios that include HD Radio capability in recent years, but those same units also support streaming apps with a lot more to offer -- apps that people are generally more familiar with than HD Radio.

I just don't see AM radio saving itself with HD Radio technology whether it's IBOC or digital-only. Those stations should keep their heritage analog signal and use it to promote the hell out of their better sounding digital platforms.

I challenge anyone to point to improved ratings that any AM station has achieved as a result of using HD Radio on AM.
 
AM receivers had reduced bandwidth as early on as the 1980's. Manufacturers also narrowed the received bandwidth of AM broadcasts to try to reduce RFI from power supplies and the like. Increased RFI has more to do with AM's demise than IBOC.
 
No difference today. WINS is now HD but no HD on WCBS. Does anyone know if they plant to turn it back on?
 
WINS and WCBS are co-owned. I would imagine it's just a case of getting the HD signal back on WCBS. I doubt Entercom wants it on 1010 but not on 880. I have HD radio in the car and WINS clearly sounds better. Although I think the FM HD signal is better still. So when I want to hear WCBS, I go to WCBS-FM-HD-2. And when I want WINS I go to WNEW-FM-HD-3.

The shut down of the HD signal may also have something to do with so many of the staff working from home. WCBS has no dual anchor hours at this point. Since everyone is working from home, all the hours have single anchors. In AM drive and PM drive, the two anchors alternate hours. WINS never had dual anchors, so WINS's anchor schedule stayed the same.

BTW, I also notice WINS had taken its teletype sound effects off the air after the anchors started working from home. I heard it back a few weeks ago during one anchor's shift. But listening the last couple of days to hear the HD signal, I don't hear the teletype machine at this point. KYW Philadelphia, which also had been using teletype, announced this month it was discontinuing the sound effect. WINS and KYW had been owned by Group W, which kept the sound after all the CBS all-news stations gave it up. So even after the merger, both stations continued to use it till recently.
 
The problem is - thanks to the advent of IBOC digital broadcasting, most car manufacturers and many home receiver manufacturers have squeezed analog dynamic range reception capability from 10 kHz down to 5 kHz or even 3 kHz for units manufactured within the past decade! Why did they do this? Well, the usage of IBOC digital transmission on the AM band greatly increased the amount of noise across the band. By only allowing "narrow band" reception, unwanted interference from IBOC's sideband hash was mitigated. Other devices like set top, WiFi enabled cable boxes create plenty of interference, too, although constricting bandwidth doesn't do much to solve that issue.

That's just wrong.

There was an IBE presentation at the NAB convention around 2002 where the findings of a committee headed by Robert Orban showed that a wide selection of AM radios made in the last 20 years started rolling off around 3.8 kHz, with very little over 5 kHz and sometimes as much as 20 to 30 db below the reference 3.8 kHz level.

The presentation was intended to show that HD Radio on AM would actually have no discernible effect if stations limited bandwidth to 5 kHz.

In other words, the radios on the market for about two decades had all been limited to very narrow bandwidth so that the auto manufacturers would not get complaints about heterodynes, high noise levels, splatter, etc. This was not as much an effort to save money as it was to make AM not as subject to rising noise levels as broader bandwidth would be.

Those who have been DXers know that when there is a lot of static, narrowing the bandwidth eliminates much of the effect. Since, by 2000, nearly significant AMs that might buy HD gear were talk, the IBE committee declared that the effect of limiting the audio bandwidth would "barely if at all" be noticed.

The study is in the "Proceedings of the IBE" if anyone wants to look for them.
 
If the NAB were an honest organization that actually cared about engineering standards, instead of lobbying for IBOC on AM (so that Clear Channel and other companies with a stake in iBiquity could line their pockets), they would have instead invested all of that time & effort in lobbying the FCC to mandate improved manufacturing standards for AM radio receivers and to impose rules designed to limit AM band noise.

(I did this separately as this is a very different subject)

Nearly all the major broadcasters... from Emmis and HBC on the "less than 100 station" side to CBS, Clear Channel, Entercom and the other biggies... made "seed capital" investments in iBiquty. The idea was to create a unified front for what was a start-up so that they could go to venture capital firms for the second round of financing.

At that time, all major broadcasters believed that radio needed to be able to say "digital". This was the beginning of the digital age, accentuated by the release of the iPod in late 2001 and fortified by the growth of downloading of MP3 music files. Radio felt it had to be able to say "digital".

Of course, that turned out to be a chimera. People did not want digital per se; they wanted free music of their picking with no ads.

But broadcasters... essentially all of us... thought HD was the digital answer. And we went along with a version for AM only because we thought the FCC would not approve a system that further sunk AM into irrelevance. We created committees to make sure the FM HD channels had a wide variety of novel and unique formats (I was HBC's delegate to that abortive fiasco). We ran ads on the air, even promoting retailers that sold or installed HD radios, like Best Buy and Circuit City.

But none of us thought we'd make money from investing in HD. Some of us also invested in Satellite at the same time to cover all options (I oversaw the programming of the 5 HBC channels in Spanish while also working with the HD committee). The idea was to have at least one passenger on every plane that took off... even if the concept did not work in the long run.

In fact, the broadcaster investments in HD were so small that they were not even listed in the annual reports of the companies that bought initial participations; the amount was below the obligatory disclosure levels. I believe that every company that bought start-up equity lost money as the later stages diluted the investments so much since iBiquity was hardly a massive success (iBiquity filed for bankruptcy in 2008 and even got some Maryland state money to avoid the doors closing completely).
 
^^^^^ True enough. Even as early as 1990 the word "Digital" had some sort of magic attached to it. My 1990 CD Boombox had the word "DIGITAL" plastered on the front -- the idea that you had "digital" sound made it seem new, modern, futuristic.

I also recall when HD radio was first publicized. I was working in the industry at the time, and it was thought to help OTA radio compete with satellite, which at that time was feared to be the medium that might cut into radio's listenership. Also, the idea of digital radio helped in promoting radio as being updated, new, etc. The movers and shakers at the company I worked for were excited enough about the technology (and the chance for new venues to sell their programming) that they brought it up at the company meetings.
 
Interestingly enough, I find the HD AM signal of WINS is now much stronger and more stable. In the past, I had trouble holding onto their HD signal. I listened to it yesterday in my car and yes it faded a few times but I never lost the HD lock. It also seems to sound a bit better than it did in the past. I have not tried it after sunset but now I don’t necessarily need to change to 102.7 HD3. I hope WCBS also re-enables it’s AM HD soon. It would be nice to see other AM stations in the market to use HD.
 
At that time, all major broadcasters believed that radio needed to be able to say "digital". This was the beginning of the digital age, accentuated by the release of the iPod in late 2001 and fortified by the growth of downloading of MP3 music files. Radio felt it had to be able to say "digital".
Maybe, but the original intent of IBOC DAB (HD Radio) was to create an alternative to the European DAB system that preserved the differences in power level and signal coverage between the different stations in a market, and the relative difference in audio quality between AM and FM, unlike DAB which gives every station in a market the same coverage (more or less), regardless if it was originally a 250-watt AM station or a 50,000-watt FM station.

I remember reading an electronics magazine in 1993 with an article promising that IBOC DAB was "right around the corner". They were only off by about a decade.
 
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