HD Radio: The Digital Standard You Never Heard About!

January 31st, 2017

When I interviewed CNET’s “Audiophiliac,” Steve Guttenberg, on last weekend’s episode of The Tech Night Owl LIVE, he mentioned the potential end of FM radio in Europe. It’s already history in Norway, but the chances that it’ll go away in the U.S. are probably on the low side of zero. Still, terrestrial radio appears to be losing the war what with the growth of satellite radio, Internet radio, streaming music and other mediums that compete for your listening pleasure.

I say that as the host of two syndicated radio shows that are featured on several dozen AM and FM stations. It’s in my vested interest for them to live long and prosper.

But these old fashioned radio formats are highly flawed. Unless you’ve got a strong signal, AM reception may be noisy, or vary in quality. A benefit of AM, however, is long distance reception. At night, when the signals reflect off the ionosphere (skywave or skip propagation), you can sometimes hear stations that are up to thousands of miles away. I remember dx-ing radio when I was young. After the sun went down, I’d sweep through the dial and hear stations at my home in Brooklyn, NY from as far away as Chicago and Atlanta. It was real fun.

In my early days as a radio broadcaster, I worked in small towns in the south and midwest, but would pay close attention to the music that debuted onn the big city stations in New York, Chicago, Minneapolis-St. Paul and elsewhere.

With the growth of FM, most music left AM and its lower quality audio and was largely replaced by talk. FM delivers clean, crisp sound mostly free of hiss within its useful range. But FM has its disadvantages too. Beyond 30 or 40 miles, or when being reflected off large buildings, an FM signal may be static-ridden.

While it doesn’t extend the range of AM and FM, HD Radio embeds digital signals onto the transmissions. When it works, the AM signal comes close to FM in listening quality. FM approaches a CD. Even better, an FM station may broadcast multiple signals, so in addition to HD1, the main signal, there may be an HD2 and an HD3. Station owners sometimes create separate channels, or just include content from their AM outlets. In the Phoenix area, it’s a bit of both.

Now HD Radio is not something you can simply add with a cheap adaptor. Your radio, car or home, must be equipped with the feature. Many recent autos have HD. After-market auto receivers may have them too. When it comes to the home, most of the offerings are restricted to FM tuners and receivers. There are a few table top and portable radios available if you look, but the selection is limited.

Unfortunately, the folks at iBiquity, who license the technology, do not seem to have invested much in promotion. You know it’s in your car if HD is mentioned in the specs. Home radios that include HD mostly list it in the model name or specs without explanation. It’s the sort of feature that exists under the radar, and that’s unfortunate.

Yes, HD Radio has its limits. If the signal isn’t strong enough to sync to the digital band, you may be limited to the regular signal. It usually takes five or 10 seconds for the radio to switch over, and if signal quality dips or is marginal, the digital carrier may be lost. Consumer Reports magazine, when reviewing car radios with HD Radio, has complained of its knack to switch in an out, depending on signal quality. The magazine suggests you avoid HD when you buy a car, but that’s preposterous. It’s either there or it isn’t, and it’s usually not a separate line item on the custom order slip. Normally it’s switched on automatically, but some car infotainment systems may have an option somewhere to switch it off if you’re not satisfied with its reception.

Now when it comes to a portable radio, I’ve actually been using one that works far better than it has the right to. Thanks to Rick at iBiquity, I recently received a SPARC SHD-TX2, a small $79.95 radio that packs a surprising punch. Thanks to a speaker with a passive radiator, its audio quality, though mono, approaches some boom boxes. Bass has a surprising thump, yet it’s only 6.2 inches wide and weighs 1.1 pounds. AM and FM reception is quite good, and it can also be configured with digital presets and Emergency Alerts.

When she’s working around our home, Barbara has been listening to a yellow Sony boom box that we originally bought for our son, Grayson, back in the mid-1990s. It still works pretty well, but goes through six “C” cell batteries far too quickly.

So I handed her the SPARC. She listened to it for a moment, and pronounced the audio quality better than that old Sony. We haven’t had it long enough to check battery life — it uses three “AA”  batteries — but she’s happy to replace her old box with something much lighter and easier to carry, at least as long as Rick lets us hold onto it.

Despite it’s shortcomings, I’m sold on HD Radio, and this little radio is a pretty cheap way to take advantage of the technology in your home. I just wish iBiquity — or its broadcaster partners — would make more of an effort to let people in the U.S. know that the format exists, and what it can do to enhance your listening pleasure.

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2 Responses to “HD Radio: The Digital Standard You Never Heard About!”

  1. John Lockwood says:

    I had to look up HD Radio as it appears to be yet another US only standard – often but not always a bad idea. Europe currently uses DAB a totally different and likely inferior standard, what is worse even though newer versions of DAB have been developed these do not appear to be being adopted or required and it appears plans are to forcible phase out the use of analogue FM in favour of this inferior first generation DAB. DAB seems to predominantly use low quality MP3 streams, sometimes even only in mono. (Norway as referred to in the article have gone down the DAB route, currently the UK uses analogue AM, analogue FM and DAB with all indications politicians plan to force us down the DAB route.)

    To give you an idea of how bad DAB streams are, they makes a low quality MP3 file look like CD quality, on top of that since DAB runs over FM frequencies it fails to cope well with use in a moving vehicle.

    A superior alternative is DRM, DRM uses AM frequencies making it far more robust for use in moving vehicles and also uses MPEG4 e.g. AAC streams giving far better quality than the equivalent MP3 bandwidth.

    Sadly politicians are responsible for deciding to go down the route of DAB and forcing the discontinuation of analogue FM broadcasts. As we should know by now the overwhelming majority of politicians are totally illiterate with regards to science and technology. All they are concerned about is being able to then steal back the FM frequencies and flog them off to the highest bidder.

    See – https://en.wikipedia.org/wiki/HD_Radio
    See – https://en.wikipedia.org/wiki/Digital_audio_broadcasting
    See – https://en.wikipedia.org/wiki/Digital_Radio_Mondiale

    As far as I can see all these standards have significant flaws and on average deliver inferior quality to analogue FM. Sadly this is not stopping ignorant politicians rushing in to forcing their implementation. In my opinion we should wait for a better solution since such a change requires totally different hardware i.e. a radio receiver to utilise meaning any change is only going to happen once. This is why in Europe we appear to have a fate-accompli with regards to being stuck with first generation DAB. (Yuck!)

  2. dfs says:

    There are some kinds of material that are only available on one particular medium. Good luck finding a ball game broadcast on anything other than AM, for inst. Trying to shoehorn everybody into any single medium would only make radio vastly less rich and varied than it is now. I feel sorry for those poor Norwegians, who I bet weren’t allowed to vote on this new policy.

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