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sitkack

FM is so simple and robust. It should never be turned off.

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AM is even simpler and even more robust. I think we never should have switched it off.

But AM isn't switched off.

Depends where. In Switzerland it is.

I looked for a source for this but can't find any mention of it.

"Most European countries are now running a reduced AM radio service with fewer transmitters, fewer services and lower power. Albania, Andorra, Austria, Belarus, Belgium, Croatia, Estonia, Finland, Norway (except Svalbard), Slovakia, Sweden and Switzerland have completely closed their AM radio services. Denmark retains a part-time long wave service for mariners. Lithuania has closed domestic AM radio, but retains a medium wave transmitter for international broadcasting. Only Cyprus, Hungary, Iceland and Romania (together with England, Scotland, Wales, Northern Ireland and Spain) are continuing with a comprehensive AM radio service."

http://frequencyfinder.org.uk/AM_Other_Countries.pdf

This is outdated. Denmark closed its long wave transmitter last year. The biggest hold out is bbc radio 4 and they stopped special long wave programming and the service is only still on the air because it doubles as a digital signal for some power meters.

My new car doesn’t even have an AM tuner

Because it raises the costs (antenna + cable) so the profit is lower.

Most European countries have switched off all their major transmitters, or are preparing to switch off the last few that are left. E.g., in the Netherlands, there are now only low-power hobbyist stations, which will remain I think, but have a near-zero audience.

LW is simpler still and incredibly robust. It's a pity it has been turned off.

LW isn’t a modulation

Long wave is a frequency band just like medium wave. Amplitude modulation is used on both; it's the same technology, LW needs much larger antennas though. FM is often used to refer to a frequency band, but that is actually called ultra-short wave, and frequency modulation is used on it.

AM sounds painfully awful

For a while there was an AM Stereo which sounded much better

And there are some stations in the US still broadcasting in AM Stereo AKA C-QUAM, if you have an AM stereo capable receiver that is.

https://en.wikipedia.org/wiki/C-QUAM

You should listen to some DAB+ for comparison. I heard that 56kbps can make wonders. /s

That's he-aac so 56kpbs is not that bad, it gets dicey below 32kbps when you need tricks like parametric stereo. But he-aac's spectral band replication does add metallic taste to everything, i would agree

Agree for music. Hard disagree for voice.

Especially in the car! I can’t make out voices on FM at all. But AM, easy.

That "sound" is partially due to the design of the current AM system. It was built to pack more transmitters into the allocated frequency range.

There are no technical impediments to high fidelity audio because of amplitude modulation. In the past the big limitation was the bandwidth of intermediate frequency (IF) amplifiers in the receivers which were typically tuned for maximum gain and not flat audio band response. The transmitters have flat response out to the legal limits. Radio stations have a monitor receiver that has proper IF audio response and the sound of those are very good.

So does DAB. It’s way the hell compressed.

Not that I care too much, as I basically only do on demand media these days.

In the US, AM is still very common and there are efforts to keep it that way: https://news.ycombinator.com/item?id=40234871

AM was switched off?

It sucks though, sounds horrible.

I wouldn't say it's more robust. One pass under a bridge proves that AM has problems.

It also has lower fidelity.

AM only has lower fidelity because of the low broadcast power and shitty receivers. 80 years it was much higher quality with the huge transmitters and high quality tube radio.

I'm going to dust off my spark gap radio.

In the US, our "HD" radio (we don't have DAB) sounds so bad, I end up turning it off and listening to the analog version.

It sounds like they reduced bitrate by pitch-shifting down prior to transmission, and then pitch-shifting back up at playback. Everything just has this metallic ring to it: When I tried the classical station, at first I thought there was bells in the piece they were playing until I realized it was a compression artifact. When I listen to talk, I keep hearing a bell/ringing over everyone's voice.

I know a lot of the newer codecs also sound great (for the car) at low bitrates, so I don't want to go and blame "quantity over quality."

The whole "HD" thing of HD Radio was a deception to begin with. It blatantly played on the understanding of HD as "high definition", when all it actually meant was Hybrid Digital, i.e. you get a digital audio stream that falls back to a simulcast FM with insufficient signal strength or exceeding error correction thresholds.

When I read about it years ago, It was made out to have a very high bitrate (and quality) if the analog FM signal was replaced completely by a digital signal.

Digital audio is also relatively expensive for some people. There are people who in my community who ride around on their bikes listening to fm radio. A monthly data fee could be hard for some.

I have never heard of DAB or DAB+ requiring monthly subscription fees? At least I don't pay any, and I have a DAB+ receiver in my car

Listening to DAB on a cellphone requires a monthly data plan.

You listen to DAB using a DAB radio like you listen to FM broadcasts with an FM radio.

If you’re listening to something on your phone through a data plan, it’s not DAB, but an unrelated streaming service.

Not having a radio receiver in a phone has always been one of those WTF things for me. There have been articles on why iOS doesn't have a radio tuner even those the receiver is there claiming because it would divert users from apple music or whatever. It's always felt like a missed opportunity to me though

Phones used to have fm receivers! It was common in the early 2010s. They used the headphone cord as an antenna.

Unihertz phones still do (even the tiny Jelly Star)

The main reason to not have it is that unless you’re out of cellular range or has no data quota left, it’s just worse than just streaming the same stations over the internet, which also offer more content as running FM stations is expensive.

Even though older iPhone baseband chips had FM receivers, you’d still need break it out and deal with the antenna setup, with the approach taken by others requiring wired headset and shenanigans in the headphone port. That’s more BOM, and user resistance to wireless headphones or newer models whose baseband chips cut the feature.

It used to be a somewhat common feature in phones (including smartphones from other brands), but it usually had quite “eh” reception. And with transitions to DAB, the feature becomes unusable without DAB decoders which I’m sure someone is claiming royalties for.

There's one place where I still bring my old cell phone to use the FM receiver part: sports events. It's nice getting the announcers live instead of on a broadcast delay + digital buffer. Through the internet it's usually several seconds behind the action but on the local low power FM broadcast it's practically zero latency.

> Listening to DAB on a cellphone requires a monthly data plan.

Cellphones used to include AM/FM radios.

Personally I think it might be useful to have them for public service uses: perhaps cell network are more robust than a few years ago, but there are still instances when they could be (are) overwhelmed, and a broadcast-only system could be useful in major emergency events.

Hard to have an antenna with wireless headphones.

hard to have an efficient VHF antenna using traditional designs

Smartphones a lot* of antennas, but most target 1/10th the wavelength of FM radio.

Cell systems still have the ability to push out a message regardless of how "overwhelmed" the towers are. They'll just drop service to some customers while the higher priority emergency message is broadcasted out.

A cell network doing a one-way broadcast text message to all clients is a solved problem. And honestly, I greatly prefer this way to push out an emergency message than assume I'm tuned to a radio station or broadcast TV, two things I'm rarely doing. I'm way more likely to be listening or watching local or streaming media instead of watching broadcast TV. Or even just not be doing any of that at all. Lots of people I know wouldn't even be able to tune into a broadcast TV or FM radio station outside of their cars.

I wouldn’t mind if those people blasting FM radio used headphones. I don’t believe it’s because they can’t afford them.

Not a good idea on a bike

I've heard this assertion many times. But after having ridden hundreds (thousands?) of hours wearing headphones, I must conclude that it's a perfectly fine idea. People believe headphones will obstruct your hearing. Some do. Some don't. Wear the ones that don't. It's also possible to set the volume to the same level that it would be from a set of handle-bar mounted speakers.

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