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Technology of radio

M

MerlynKing

New Participating Member
Analog modem has a maximum download rate of 53.3 kbit/s. There are 19 genres of music on FM radio: Jazz, Adult Album Alternative, Top-40, Spanish Pop, Ethnic, Hot AC, Rock, Country, Religious, Hot AC, Classic Rock, Rock, Spanish Pop, Christian Contemporary, Hip Hop, Tropical, Adult Contemporary, Christian Contemporary, Urban Contemporary,
and 2 on AM radio: Spanish Christian, and Gospel Music.

What we really needed was an audio codec (XM uses HE-AAC, HD radio uses PAC) that got the best sound possible at whatever AM can broadcast at, which according to the wikipedia is 40 kbps, and then emphasized multicasting for FM so that more genres can be available in more locations. The biggest market is NYC.

The thing is, I think the technology was launched before it was ready, there is now HE-AAC-PS which should sound superior at 40 kbps. Then there's the AMBE codec that I'm not sure can go to bit rates that high.

And I would also point out - there is Music Choice on HDTV. Why not have the genres reflect radio genres so we don't hear "Jet Airliner" over and over again?
 
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MerlynKing said:
Analog modem has a maximum download rate of 53.3 kbit/s. There are 19 genres of music on FM radio: Jazz, Adult Album Alternative, Top-40, Spanish Pop, Ethnic, Hot AC, Rock, Country, Religious, Hot AC, Classic Rock, Rock, Spanish Pop, Christian Contemporary, Hip Hop, Tropical, Adult Contemporary, Christian Contemporary, Urban Contemporary,
and 2 on AM radio: Spanish Christian, and Gospel Music.
Click to expand...

Are you speaking of your particular market? I ask because there are certainly more formats than just those mentioned, such as Alternative Rock, Classic Rock, Classic Country, classic hits, oldies, soft AC, Adult Hits, Churban, CHR, etc.

In Spanish language formats, there are rock, adult hits, pop, rhythmic/reggaeton, Regional Mexican, ranchera, grupera, Tejano, Caribbean Tropical, Mexican / Central American Tropical, AC and several others.
 
What is the question or point? There are literally a dozen different codecs used for audio streaming.
 
MerlynKing said:
Analog modem has a maximum download rate of 53.3 kbit/s. There are 19 genres of music on FM radio: Jazz, Adult Album Alternative, Top-40, Spanish Pop, Ethnic, Hot AC, Rock, Country, Religious, Hot AC, Classic Rock, Rock, Spanish Pop, Christian Contemporary, Hip Hop, Tropical, Adult Contemporary, Christian Contemporary, Urban Contemporary,
and 2 on AM radio: Spanish Christian, and Gospel Music.

What we really needed was an audio codec (XM uses HE-AAC, HD radio uses PAC) that got the best sound possible at whatever AM can broadcast at, which according to the wikipedia is 40 kbps, and then emphasized multicasting for FM so that more genres can be available in more locations. The biggest market is NYC.

The thing is, I think the technology was launched before it was ready, there is now HE-AAC-PS which should sound superior at 40 kbps. Then there's the AMBE codec that I'm not sure can go to bit rates that high.

And I would also point out - there is Music Choice on HDTV. Why not have the genres reflect radio genres so we don't hear "Jet Airliner" over and over again?
Click to expand...

Is the idea for an alternative digital format to HD for AM? Or to prepare the country for an all-digital scenario like Norway? I'm scratching my head in confusion...

Problem I see in all this is the manufacturers don't want to do anything new. HD has fairly low penetration in cars and even lower in tabletop/portable. It has been an uphill battle to pique interest in digital radio when cellphones, tablets, etc. are increasing technology exponentially. To create a new standard, turning most of these HD radios back into analog only pieces, (not to mention all the cars who have navigation systems using HD traffic) then create a new system to shill out new radios, in an industry that at best overall is flat in its revenue...it'd be a hard, hard sell.

That being said, I am in agreement with you that AM needs something, anything to make it a bit more appealing. The all-digital AM tests went well recently, and I could see that being a potential help to the slowly suffocating AM band.

Radio-X
 
Radio-X said:
Problem I see in all this is the manufacturers don't want to do anything new.
Click to expand...

Exactly, and manufacturers are typically not making products specifically for the US market. So if this is a US system, good luck getting radios that will receive it.

The weakest link in the radio chain today is the lack of devices. Electronics manufacturers are no longer investing any time in creating fun radios. The last one may have been the Walkman over 25 years ago. We have a generation that's grown up since then, and during that time, they don't even know that radios can be portable. They think of them as something attached to something else, like a car. This is a big problem, especially when we're talking about technical improvements to audio quality.

What is needed is for companies with something to gain, specifically radio owners, to get involved in radio manufacturing. Can you imagine if a radio company had invented the Amazon Echo, and it included an FM radio? As it is, it will get you FM stations on TuneIn, but not OTA. This is the kind of product that might revive interest in radio.
 
One of the main issues is sideband interference. This relates to bandwidth. I did some CD rips at different bit rates with different audio encoders to see what the bandwidth is at different sampling rates. I didn't use a switch to change the sampling rate, the encoder is preprogrammed to use a particular sampling rate at different bit rates.

dbPoweramp Lame MP3: (freeware audio encoding, proprietary container)
8 kbps at 8 kHz,...,24 kbps at 8 kHz sampling rate, 32 kbps at 16 kHz sampling rate, 40 kbps at 16 kHz, 48 kpbs at 22 kHz, 56 kbps at 24 kHz, 64 kpbs at 24 kHz, 112 kpbs at 44.1 KHz

WMP WMA Pro: (proprietary)
32 kpbs at 32000 sampling rate, 48 kbps at 44100 sampling rate

iTunes AAC (proprietary):
64 kbps at 44100 sampling rate

Winamp Ogg (free):
48 kbps at 44100 sampling rate

EAC MPC (free):
84 kbps at 44100 sampling rate

The most important consideration is low probability of error - to get a large broadcast range. From what I've read stations that broadcast in HD had to turn up the power to get the same broadcast range they had before.

To get as many as 21 genres from a single station, engineers need to come up with some mega modulation scheme with a high bit rate per second and a low probability of error. I think this is more likely possible for HD FM than HD AM.
But a multicast AM station could play reruns of Rush, Glenn, and Sean 24/7, and have another channel where all the local sports are broadcast including the highschool football game.

Maybe we should figure out what the ideal digital system is, and first convert the analog broadcasts to a new age analog system first. Because there is a hybrid digital stage before the broadcasts are all digital.

Note on mp3: the industry standard encoder for mp3 is Franhauffer, available with shareware Winamp pro, which AFAIK is still licensed for commercial use. LAME is a freeware mp3 encoder that produces audio in the same file format.

As far as licensing fees. The industry standard archive for digital music is 384 kbps mp2. Digital audio files are sold in mp3 or flac format. Flac is lossless, so the bandwidth is too high for open air broadcast. The bit rate for a CD is 1411.2 kbps. Flac files are about half of that.

Radio stations need to pay for the licensing encoding of their archive and for the encoding of the songs with each broadcast. The encoder for broadcast is PAC (perceptual audio codec) that was made by Lucent Technologies. The thing that concerns me is not the licensing fees themselves but the labor hours in documenting that the fees have been paid to the appropriate artist. Which is why I vote for LAME mp3 as the industry standard.

In fact, I think pay for play should be legalized and licensing fees elminated for radio stations. The only way they are economical for the RIAA is as a form of advertising. This way, record companies can send thumb drives to radio stations around the country with the week's new releases.
 
TheBigA said:
Exactly, and manufacturers are typically not making products specifically for the US market. So if this is a US system, good luck getting radios that will receive it.

The weakest link in the radio chain today is the lack of devices. Electronics manufacturers are no longer investing any time in creating fun radios. The last one may have been the Walkman over 25 years ago. We have a generation that's grown up since then, and during that time, they don't even know that radios can be portable. They think of them as something attached to something else, like a car. This is a big problem, especially when we're talking about technical improvements to audio quality.

What is needed is for companies with something to gain, specifically radio owners, to get involved in radio manufacturing. Can you imagine if a radio company had invented the Amazon Echo, and it included an FM radio? As it is, it will get you FM stations on TuneIn, but not OTA. This is the kind of product that might revive interest in radio.
Click to expand...

You are absolutely correct and your point just seems to be lost on the companies who advertise themselves as "pureplay" radio. There is a company head who has beat the drum for lighting up the chips in smartphones and that's all you ever heard from the guy. He is in a position to lead but you hear nothing about involvement in the development of technology and the manufacture of radio devices.
Think about it further...radios could become hybrid devices which use both terrestrial RF for delivery (just like a UDP stream) and the cloud for the listener to station connection. Imagine the metadata they could gather...spots could target specific people at specific locations. The commercials could be loaded overnight. Use your imagination...the possibilities are endless.
None of this will happen unless the industry makes it happen. Radio owners need skin in the game. Big A is right on the money...it will NOT happen unless radio ownership makes it happen.
 
MerlynKing said:
One of the main issues is sideband interference. This relates to bandwidth. I did some CD rips at different bit rates with different audio encoders to see what the bandwidth is at different sampling rates. I didn't use a switch to change the sampling rate, the encoder is preprogrammed to use a particular sampling rate at different bit rates.

dbPoweramp Lame MP3: (freeware audio encoding, proprietary container)
8 kbps at 8 kHz,...,24 kbps at 8 kHz sampling rate, 32 kbps at 16 kHz sampling rate, 40 kbps at 16 kHz, 48 kpbs at 22 kHz, 56 kbps at 24 kHz, 64 kpbs at 24 kHz, 112 kpbs at 44.1 KHz

WMP WMA Pro: (proprietary)
32 kpbs at 32000 sampling rate, 48 kbps at 44100 sampling rate

iTunes AAC (proprietary):
64 kbps at 44100 sampling rate

Winamp Ogg (free):
48 kbps at 44100 sampling rate

EAC MPC (free):
84 kbps at 44100 sampling rate

The most important consideration is low probability of error - to get a large broadcast range. From what I've read stations that broadcast in HD had to turn up the power to get the same broadcast range they had before.

To get as many as 21 genres from a single station, engineers need to come up with some mega modulation scheme with a high bit rate per second and a low probability of error. I think this is more likely possible for HD FM than HD AM.
But a multicast AM station could play reruns of Rush, Glenn, and Sean 24/7, and have another channel where all the local sports are broadcast including the highschool football game.

Maybe we should figure out what the ideal digital system is, and first convert the analog broadcasts to a new age analog system first. Because there is a hybrid digital stage before the broadcasts are all digital.

Note on mp3: the industry standard encoder for mp3 is Franhauffer, available with shareware Winamp pro, which AFAIK is still licensed for commercial use. LAME is a freeware mp3 encoder that produces audio in the same file format.

As far as licensing fees. The industry standard archive for digital music is 384 kbps mp2. Digital audio files are sold in mp3 or flac format. Flac is lossless, so the bandwidth is too high for open air broadcast. The bit rate for a CD is 1411.2 kbps. Flac files are about half of that.

Radio stations need to pay for the licensing encoding of their archive and for the encoding of the songs with each broadcast. The encoder for broadcast is PAC (perceptual audio codec) that was made by Lucent Technologies. The thing that concerns me is not the licensing fees themselves but the labor hours in documenting that the fees have been paid to the appropriate artist. Which is why I vote for LAME mp3 as the industry standard.

In fact, I think pay for play should be legalized and licensing fees elminated for radio stations. The only way they are economical for the RIAA is as a form of advertising. This way, record companies can send thumb drives to radio stations around the country with the week's new releases.
Click to expand...

I'm not sure the bandwidth is there for multicast AM....I would be happy to see something that is a single "listenable" channel. There are much better encoding methods for low bandwidth paths but Ibiquity has a stranglehold on digital in the USA. Listen to DRM which is used on shortwave and, I think, in most of Europe. I have heard the shortwave and it's much better than US AM.
Of course, DRM is not compatible with analog. It is time to sunset analog AM and force a digital solution. I have heard all the arguments about analog so keep a few analog AM stations for emergency communications. Let the rest switch...or turn them off.
 
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First off, most stations today use WAV files to store their music, not MP2, and definitely not MP3 or WMA. Podcasts or archival material may be a different story.

MP3 is not a suitable choice for digital radio broadcast - the quality at low bit rates is far too low. No matter which encoder is chosen.

If there were going to be a change away from Ibiquity's IBOC system, it would have to be to the European system. There's no reason to invent something different.

I'm not sure how we got from digital audio encoding to whether or not the government should legalize payola!!!

I'm also not sure how an analog modem got involved in the thread. The 53.3 kbps was a limitation of the copper telephone system, which was designed for low-quality audio.

It's a strange thread...
 
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