Just curious: DVB radio capture

[pawel]

Folks, what about digital capture of radio broadcast via DVB-C/S/T cards or tuners? It isn't stated in the FAQ, however, if read strictly it may not be allowed on TTD. Am I right?

If not then I'd like to ask to accept such recordings if they are in native format: MP2 or AC3 - not converted to wav/aiff.

Don't be fooled with nowadays analog captures, there are very often in much worse quality than digital. It's no longer FM from 20 years ago... Now, all stations use compression, and amplitude amplification.

So?

[rhinowing]

just put it on dime, I doubt that native format lossy captures will ever be allowed here--check out the thread about MP3 master recordings for more info on this one, I believe its in technobabble

[Five]

Originally Posted by pawel

Don't be fooled with nowadays analog captures, there are very often in much worse quality than digital. It's no longer FM from 20 years ago... Now, all stations use compression, and amplitude amplification.

So?

show me the money... something captured from an open air broadcast and similtaneously captured from the pure source digital stream and we can begin to consider it.

right now the policy is that if it is recorded from the open air, it is okay, even tho many stations are broadcasting lossy at least it has a predictable cutoff.

All FM stations use lossy compression (mp3, mp2, ac3) these days? Just a couple of years ago I recall hearing CDs skip during FM broadcasts occasionally.

You would think for quality purposes they would EAC and FLAC their audio discs, put them on a server and broadcast analog FM from that, with on the fly ac3 compression for digital broadcasts (if they simulcast in digital, like HD FM). But maybe it is easier (less drive space) just to compress them all to ac3 or mp2 and broadcast everything from that.

What would sound better:

1)audio CD > EAC > .wav > high bitrate ac3 > digital broadcast > digital capture w/no lossy reencoding

or

2)audio CD > DA converter > analog FM broacast with amplitude compression > FM stereo receiver w/good reception > AD converter > .wav > FLAC

Would the redigitization and FM compression make #2 sound worse than #1, even though it is lossless? I guess it all depends what the bitrate of the lossy broadcast is.

[rhinowing]

one in most cases IMO

[Five]

well apparantly the bbc is using 10bit/32kHz WAV but as for what they do at other stations ymmv

flac and eac are not very well known outside of hobbyists in my experience.

If it sounds better, then maybe they should consider allowing high bitrate lossy digital broadcasts. I think just like analog TV, analog radio will cease to exist someday; it will all be lossy digital.

If you had limited bandwidth for a digital broadcast, which would you rather broadcast in: high bitrate lossy stereo 24/48 DTS, or lossless 16/44.1? I think some, esp. here at TTD, would choose the lossless 16 bit, even though it won't sound nearly as good!

Oh shit, 10bit/32kHz .wav?? That is certainly craptacular, I had no idea their bandwidth was so restricted.

Why don't they use 16/44.1 mp2? That would sound better than fucking 10 bit. and also use about the same amount of bandwidth, I think. Maybe they are worried about people ripping the broadcasts and loss of CD sales?

10bit x 32kHz x 2 channels = 640 kbps

16bit x 44.1kHz x 2 channels = 1411.2 kbps > compressed to 224 kbps mp2

Even if the 10bit x 32kHz .wav was mono, it is 320 kbps, still more bandwidth than 224 kbps mp2.

They must think broadcasting lossy 16/44.1 hurts sales.

[pawel]

I don't have access to British channels as they are on satellite which covers only the islands and a little part of France. Most continental radios use 192 kbps MP2 (48 kHz) but there are also which have AC3 448 kbps.

What I know from a friend working for a large radio company, it's very common to use lossy input files, like Tubular mentioned above. Of course it's not a case for a live gigs, unless they are post produced.

Regarding seeding on Dime, I don't like the policy because it's allowed to upload converted MP2 & AC3 to 44 kHz WAV.

[Five]

well there is also heavy dynamics compression and lpf that kills everything above aprox 16kHz which is how its always been, but it seems the source audio is not what it used to be there's a lengthy thread up in the lossy/lossless forum going on right now about this stuff...

16/44.1 sourced analog AM probably wouldn't sound too much worse than 10/32 unbelievable. Talk about devolution.

I bet someday soon all digital (TV and radio) broadcasts will be encrypted, and posting tools to break the encryption will be illegal. There will be no RCA outputs from tuners to preamps or receivers, only HDMI style secure digital connections, so they can't be redigitized. Also receivers with built in digital tuners won't be able to output a digital signal from a coax output from the digital radio/tv source, and the tape RCA outputs wouldn't work too. They won't be able to be ripped and seeded via BT, but at least then they might do away with the 10bit/32kHz garbage. They could broadcast 24/48 AC3 or DTS without fear that they will be posted to the net or ripped for personal use.

[pawel]

Originally Posted by Five

there's a lengthy thread up in the lossy/lossless forum going on right now about this stuff...

Thanks Five, I missed it. I'm reading now and unfortunately see that it confirms my observations

[pawel]

Tubular, it takes now no more than a few weeks to hack well protected software - see what happened to i.e. TMPGEnc Author 3.x - it was cracked within three months (except serial, the company uses online licence re-check).

There are plugins for DVB cards which allow to watch encrypted signal without required PPV module. So, I believe that any encryption will be soon or later cracked...