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wharfrat73
2004-11-24, 12:44 PM
I was wondering if there is a site policy regarding the recording of XM broadcasts. XM is a lossy source. By the same measurements, so is FM. Are XM and FM both banned or neither?

fatoldpig
2004-11-24, 12:56 PM
I'd like to know too. I recorded bunch of stuff too. I've connected XM line out (analog) to line in of sound card Midiman Audiophile 2496 and recording with CEP.

Rider
2004-11-24, 01:04 PM
XM is not allowed here.

wharfrat73
2004-11-24, 01:07 PM
Is FM?

Five
2004-11-24, 01:10 PM
Is FM?
Yes

wharfrat73
2004-11-24, 01:19 PM
How is it that FM is allowed and XM is not? ...just curious

Five
2004-11-24, 01:29 PM
FM (so long as it's not from a lossy source) is allowed. Even tho frequency response isn't perfect, it is free from audible artifacts associated with lossy encoding. Similar situation with 32K DAT. The freqency response is similar to some lossy formats but the offensive swish et al are not present.

oldbrokentapes
2004-11-24, 01:47 PM
Can I be so ignorant as to ask what XM is? Possibly digital radio a la DAB and DVB?

Jackstraw_1969
2004-11-24, 02:18 PM
Even tho frequency response isn't perfect, it is free from audible artifacts associated with lossy encoding.

This is not necessarily the case these days.

Stations compress their audio in many ways, and in most cases you have different compression "stacked" upon one another. Although MPEG2 has been the standard for 20 years in satellite delivery to the stations, I know of many stations that play MP3. Even if a station is playing CD's (44.1, no compression) it will get stepped on going to the transmitter.You don't even want to think about today's new HD radio!

To allow FM, and not XM or Sirrus seems like a double standard if you use the "compression" argument. Now what comes over the airwaves is "free", and XM and Sirrus are "services" so legally you may have to keep them off here anyway.

Jackstraw_1969
2004-11-24, 02:20 PM
Can I be so ignorant as to ask what XM is? Possibly digital radio a la DAB and DVB?

Satellite Radio (http://www.xmradio.com/)

Five
2004-11-24, 02:33 PM
This is not necessarily the case these days.

Stations compress their audio in many ways, and in most cases you have different compression "stacked" upon one another. Although MPEG2 has been the standard for 20 years in satellite delivery to the stations, I know of many stations that play MP3. Even if a station is playing CD's (44.1, no compression) it will get stepped on going to the transmitter.You don't even want to think about today's new HD radio!

To allow FM, and not XM or Sirrus seems like a double standard if you use the "compression" argument. Now what comes over the airwaves is "free", and XM and Sirrus are "services" so legally you may have to keep them off here anyway.
Thanks for the info, Jack. Going with the compression argument, older FMs are safe, perhaps the newer ones will need more investigation. We don't want to enforce a blanket ban on all FM sources since obviously there is no lossy source involved with a 1989 FM like the one I seeded recently. Should it come to light that all recent FM broadcasts have lossy in their lineage then perhaps we should make a "cutoff date". I believe, however, that there are still many FM stations that are broadcasting "traditional" non-mp3-sourced stuff.

RainDawg
2004-11-24, 02:37 PM
How is it that FM is allowed and XM is not? ...just curious
XM radio is a pay service that has specific agreements for users to not record and reproduce any of the material. The staff has decided we do not wish to endorse the seeding of XM radio material on our tracker.

wharfrat73
2004-11-24, 02:38 PM
All FM sources are lossy. They always have been. The question is is there a less loss source available. That, my friends, is a fine line to walk; is there - will there ever be - a TRUE SBD source available or is the best available a lossy frequency modulated source.

Jackstraw_1969
2004-11-24, 02:38 PM
Thanks for the info, Jack. Going with the compression argument, older FMs are safe, perhaps the newer ones will need more investigation. We don't want to enforce a blanket ban on all FM sources since obviously there is no lossy source involved with a 1989 FM like the one I seeded recently. Should it come to light that all recent FM broadcasts have lossy in their lineage then perhaps we should make a "cutoff date". I believe, however, that there are still many FM stations that are broadcasting "traditional" non-mp3-sourced stuff.

Keep in mind it also depends on what is being seeded. Is it live in the studio? Is it a concert broadcast from MSG? If it's the latter it gets stepped on up and down, and that is before the STL's get it. The live in the studio still has to go through the STL's tho, and all STL's wether microwave or ISDN compress.......

wharfrat73
2004-11-24, 02:39 PM
XM radio is a pay service that has specific agreements for users to not record and reproduce any of the material. The staff has decided we do not wish to endorse the seeding of XM radio material on our tracker.

Is that true of artists that do not want their art distributed electronically as well?

Jackstraw_1969
2004-11-24, 02:40 PM
XM radio is a pay service that has specific agreements for users to not record and reproduce any of the material. The staff has decided we do not wish to endorse the seeding of XM radio material on our tracker.

There you have it!

Jackstraw_1969
2004-11-24, 02:40 PM
Is that true of artists that do not want their art distributed electronically as well?

Yep......won't find any ABB here.

wharfrat73
2004-11-24, 02:44 PM
Fair enough. Let's hope that holds.

Jackstraw_1969
2004-11-24, 02:50 PM
Fair enough. Let's hope that holds.

You'll find the MOD's here to be a really good group, and they'll pull stuff if they have to, however they WILL give an explanation as to WHY.

RainDawg
2004-11-24, 02:54 PM
All FM sources are lossy. They always have been. The question is is there a less loss source available. That, my friends, is a fine line to walk; is there - will there ever be - a TRUE SBD source available or is the best available a lossy frequency modulated source.
Absolutely right. EVERYTHING is lossy, as it has to, in some way, interpret natural sound pressure fluctuations percieved by the brain as audio and record it onto some kind of media....this transition constitutes loss.

The main thrust of lossless trading stems from the belief that, once something is recorded, it should remain identical each time it is copied. Lossy codecs decrease the quality with each transfer, and to promote the idea that everyone should get equal access to identical audio, lossless codecs are used.

It is a physical fact that FM, XM, and even CD and SBD are lossy in comparison to the true signal, but this fact is beside the point here. Seeding XM radio brings about a slew of legal issues that I would rather not confront here on this site. I am sure there are places on the internet to attain this material if one is resourceful enough....

Five
2004-11-24, 03:20 PM
We use the term "lossy" a little loosely in the community... we are normally referring to 1990's lossy a la realmedia-mp3-ogg vorbis-vqa-etc. This is the kind of lossy that we're cracking down on. Hope this helps.

wazoo2u
2004-11-24, 04:18 PM
We use the term "lossy" a little loosely in the community... we are normally referring to 1990's lossy a la realmedia-mp3-ogg vorbis-vqa-etc. This is the kind of lossy that we're cracking down on. Hope this helps.
I think that we can generally agree that if the source is "FM", it's being distributed because the availability of the "Pre-FM" source is limited or unavailable. Obviously, there are different qualities of FM recordings, depending upon the type of recieving/recording equipment and the reception conditions.

All FM broadcasts are "bandwidth limited", which differs from "lossy" in the fact that full spectrum audio is bandpassed without psychoacoustic algorithms being employed to fool your ear to think all frequencies are present. Yes, limiting and compression are very prevelant in the broadcast chain, especially in the STL, but if they're analog links, they are simply amplitude envelope controls, and the basic spectrum is still passed (within the FM carrier restrictions, of course). Adding digital compression techniques that might be enountered in ISDN links as mentioned, will add an unknown factor, but I would assume that most stations would want a lossless path to their transmitter.

Could MP3 play a role in timeshifting and replaying a live concert ? It's certainly possible, but an MP3 frequency falloff might be visable before the bandpass limit, so .......

So the unknown processing in the FM path does raise questions, but all things considered, it usually means it's a recording of the most readily available source, not necessarily the best possible.

RainDawg
2004-11-24, 05:34 PM
wazoo,
Understood about the differences, but whether it's analog filtering, modulation, or perceptual coding, there is still some audio "loss" involved with the transfer....and each reduce the overall quality of the recording.

Regardless, the goal of communities like this is to find the "purest" copy possible, and losslessly spread it to others. I'm not worried about the supposedly quality loss in XM or FM broadcasts as I am the legal issues with copying XM. I accept that not much (if anything) broadcast on XM is ever likely to get into the hands of the public in it's original source form, and would be fine with XM > lossless transfers of their broadcasts were it not putting TTD into legal jeopardy.

wazoo2u
2004-11-24, 06:16 PM
wazoo,
Understood about the differences,..... and would be fine with XM > lossless transfers of their broadcasts were it not putting TTD into legal jeopardy.
I know YOU understand.... :cool:

Guess that my point was to clarify the differences between SONIC loss (loss of fidelity due to analog limitations or processing) versus MATHEMATICAL loss (which as we all know, comes from errors in creating, translating and reconstructing the digital signal).

Rider
2004-11-24, 06:26 PM
I know YOU understand.... :cool:

Guess that my point was to clarify the differences between SONIC loss (loss of fidelity due to analog limitations or processing) versus MATHEMATICAL loss (which as we all know, comes from errors in creating, translating and reconstructing the digital signal).

You kind of nailed it right there. Theres a big diifrence between a process like FM that will cut everything off at a certain level and something like MP3 which not only cuts off at cetain level but digs into what's left tries to find what no one can hear and also remove that.

wharfrat73
2004-11-24, 10:37 PM
Regardless, the goal of communities like this is to find the "purest" copy possible, and losslessly spread it to others. I'm not worried about the supposedly quality loss in XM or FM broadcasts as I am the legal issues with copying XM. I accept that not much (if anything) broadcast on XM is ever likely to get into the hands of the public in it's original source form, and would be fine with XM > lossless transfers of their broadcasts were it not putting TTD into legal jeopardy.
Well put. There's really no more to say. Thanks