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How can I tell music has been an MP3? Quantitative Measurement of Fidelity
I have been disappointed with the audio quality of some CDs I have
bought recently. Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. To get a good measure I'd expect some Fourier transforms and signal analysis to be done, so this should be relevant to sci.physics. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
On Jun 22, 6:18 pm, Dave wrote:
I have been disappointed with the audio quality of some CDs I have bought recently. Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. There's no particularly good reason why the "factory" would want to do such a things. There's a far more mundane explanation. Recent music distribution, including CDs, have suffered from an industry-wide of sever over compression, limiting and clipping, as an endemic result of the mastering process. There's been this headlong to produce "louder and louder" CDs. Many producers have decided, quite incorrectly, to equate louder with better. The result is a dramatic deterioration of available music,especially in the pop music genres. It has nothing to do with MP3, it has everything to do with overall incompetence and disregard of high production standards. To get a good measure I'd expect some Fourier transforms and signal analysis to be done, so this should be relevant to sci.physics. Nope, simply any peak-to-average measurement should reveal an overl trend in this direction over the last decade or so. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
"Dave" wrote ...
I have been disappointed with the audio quality of some CDs I have bought recently. This has been discussed many times in the recent past. Note that far and away the prime suspect is hyper-compression (compression of the audio levels, NOT data compression of the signal stream.) Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) 1) SNR is not "an accepted measurement of fidelity" 2) There is no specific "accepted measurement of fidelity" "Fidelity" is a combination of many things. Some subjective. 3) It would be difficult-to-impossible to actually meausre SNR on a commercial CD because of the way they are mastered. (i.e. there is no "baseline" because it is usually muted) I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. Did you buy these CDs from the back of Guido's white van? Do you know they are legitimate and not pirated copies? Seems very unlikely that commercial CDs would have ever been processed through any such gross lossy step as MP3 compression. To get a good measure I'd expect some Fourier transforms and signal analysis to be done, so this should be relevant to sci.physics. It has been discussed here before that there are relatively easy ways of analyzing audio to detect lossy compression such as MP3. Many people claim they can hear it easily. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
On 22 Jun, 23:54, "Richard Crowley" wrote:
"Dave" wrote ... I have been disappointed with the audio quality of some CDs I have bought recently. This has been discussed many times in the recent past. Note that far and away the prime suspect is hyper-compression (compression of the audio levels, NOT data compression of the signal stream.) Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) 1) SNR is not "an accepted measurement of fidelity" 2) There is no specific "accepted measurement of fidelity" "Fidelity" is a combination of many things. Some subjective. 3) It would be difficult-to-impossible to actually meausre SNR on a commercial CD because of the way they are mastered. (i.e. there is no "baseline" because it is usually muted) Have there been no bright PhD students sponsored by the music industry, or are they too busy with their revenue stream? The noise is what is not the notes. For a symphony you have an idea of what the notes should be, because you have the sheet music, and you know what a violin, flute etc should sound like. You may be able to measure something more because that is what the brain does. I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. Did you buy these CDs from the back of Guido's white van? Do you know they are legitimate and not pirated copies? Seems very unlikely that commercial CDs would have ever been processed through any such gross lossy step as MP3 compression. Business takes the route of maximum profit. To get a good measure I'd expect some Fourier transforms and signal analysis to be done, so this should be relevant to sci.physics. It has been discussed here before that there are relatively easy ways of analyzing audio to detect lossy compression such as MP3. Many people claim they can hear it easily. The method I saw was looking for high frequency cut off. Is this was you were thinking of? |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
"Dave" wrote ...
, "Richard Crowley" wrote: 1) SNR is not "an accepted measurement of fidelity" 2) There is no specific "accepted measurement of fidelity" "Fidelity" is a combination of many things. Some subjective. 3) It would be difficult-to-impossible to actually meausre SNR on a commercial CD because of the way they are mastered. (i.e. there is no "baseline" because it is usually muted) Have there been no bright PhD students sponsored by the music industry, or are they too busy with their revenue stream? The noise is what is not the notes. For a symphony you have an idea of what the notes should be, because you have the sheet music, and you know what a violin, flute etc should sound like. You may be able to measure something more because that is what the brain does. That is just impossibly simplistic. There is a great deal of stuff "between the notes" besides noise. Have you done much recording yourself? I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. Did you buy these CDs from the back of Guido's white van? Do you know they are legitimate and not pirated copies? Seems very unlikely that commercial CDs would have ever been processed through any such gross lossy step as MP3 compression. Business takes the route of maximum profit. If you dont' want to reveal any clues that would help answer your question, its up to you. To get a good measure I'd expect some Fourier transforms and signal analysis to be done, so this should be relevant to sci.physics. It has been discussed here before that there are relatively easy ways of analyzing audio to detect lossy compression such as MP3. Many people claim they can hear it easily. The method I saw was looking for high frequency cut off. Is this was you were thinking of? No, there are supposed to be other "markers" of MP3-style compression. But I didn't pay attention to what they were or how to find them because I'm not particularly concerned. I use MP3 only as a last-step release format. |
How can I tell music has been an MP3? Quantitative Measurementof Fidelity
Dave wrote:
I have been disappointed with the audio quality of some CDs I have bought recently. Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) Some famous commercial recordings have a low s/n being recorded at home. I had assumed my cassette tape (forget which song now) was bad till years later when I bought a CD and it sounded the same. A few issues ago Maximum PC did a comparison among lossless codecs and at 192 kb/s there was only one track where any difference could be heard. Now mp3 is a lossy codec, but at higher bitrates I doubt there is much difference in the sound. For mp3's I suspect that 256 kb/s is where you'll have difficulty telling the difference. I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. Long ago I made a custom CD for my wife's aunt and I ripped wav files from her CD's and remastered the tracks she wanted. She was very pleased with the results. Less long ago she wanted another CD. I had forgotten where I put them and when I found them this time I ripped mp3's at 128 kb/s and remastered the CD, she was very disappointed with the quality this time. As I recall I needed to free up some disk space at that time so this seemed quickest. But obviously mp3's are not as good as the original wav files. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. There may be another way, there is a public database of CD's, immdb or something like that. I'm not sure how they identify the CD, perhaps the volume name, but I suggest that any casually remastered CD, or any made from mp3's from the net won't have the same volume name, or whatever they use. That is, I suggest you rip the tracks from the CD with some software that can identify the disk from immdb, if it cannot identify the CD, there's a good chance it's as you suspect. Unless you've for some obscure latin CD or something, the database is not complete, but for any popular release this should work. I think Nero will do this, I've not done it for years though. Note, you don't have to rip the tracks, just see if the CD can be identified. Cheers, Rich To get a good measure I'd expect some Fourier transforms and signal analysis to be done, so this should be relevant to sci.physics. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
In rec.audio.tech Dave wrote:
I have been disappointed with the audio quality of some CDs I have bought recently. Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. Unless these are pirated copies, the answer is most likely not. That's too much pointless effort for commercial studios to go through. The answer is much more mundane: Most recording sucks. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
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How can I tell music has been an MP3? Quantitative Measurement of Fidelity
On Jun 23, 10:18 am, Dave wrote:
I have been disappointed with the audio quality of some CDs I have bought recently. Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. To get a good measure I'd expect some Fourier transforms and signal analysis to be done, so this should be relevant to sci.physics. The SNR or more correctly the signal to quantization noise level depends on the sampler. For N bits it is approx 6N. So for 16 bits it is 96dB. You will never hear the quantization noise. Compression is a different matter |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
On 23 Jun, 03:43, "Richard Crowley" wrote:
"Dave" wrote ... , "Richard Crowley" wrote: 1) SNR is not "an accepted measurement of fidelity" 2) There is no specific "accepted measurement of fidelity" "Fidelity" is a combination of many things. Some subjective. 3) It would be difficult-to-impossible to actually meausre SNR on a commercial CD because of the way they are mastered. (i.e. there is no "baseline" because it is usually muted) Have there been no bright PhD students sponsored by the music industry, or are they too busy with their revenue stream? The noise is what is not the notes. For a symphony you have an idea of what the notes should be, because you have the sheet music, and you know what a violin, flute etc should sound like. You may be able to measure something more because that is what the brain does. That is just impossibly simplistic. There is a great deal of stuff "between the notes" besides noise. Have you done much recording yourself? It doesn't sound as complicated as fusion, and that is having billions spent on it. Besides I thought banks and defence liked graduates with in-depth signal analysis experience. I have listened to plenty of CD (about 650), so I think I can tell a good recording from a bad one. There may be problems of course with quantative measurement, in that the recording could be done to get the measurement high, and it could just sound clinical. The point was that if I thought a CD sounded poor quality I think there should be a computer program to confirm this, instead of just asking someone else. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
On 23 Jun, 06:44, "Colin B." wrote:
In rec.audio.tech Dave wrote: I have been disappointed with the audio quality of some CDs I have bought recently. Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. Unless these are pirated copies, the answer is most likely not. That's too much pointless effort for commercial studios to go through. The answer is much more mundane: Most recording sucks. Maybe I should retrain when I get to 50 because by then all younger sound engineers will have grown up with MP3s and not have a clue what decent audio sounds like. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
In article ,
Colin B. wrote: There's a far more mundane explanation. Recent music distribution, including CDs, have suffered from an industry-wide of sever over compression, limiting and clipping, as an endemic result of the mastering process. I'd suggest that this isn't a recent phenomenon. I've got plenty of pop vinyl from the 1970s and 1980s that has roughly no dynamics. Making crap sound louder on the radio at the complete expense of quality is decades old. There's a difference in how this was acheived, though. In older days it was through the arrangement of the music and studio recording practices. The Phil Spector 'wall of sound' for example. These days it's done using largely automatic processors after the studio recording is signed off. Similar to the types used for processing radio at the transmitters. -- *Does fuzzy logic tickle? * Dave Plowman London SW To e-mail, change noise into sound. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
In article .com,
Dave wrote: I have been disappointed with the audio quality of some CDs I have bought recently. Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. To get a good measure I'd expect some Fourier transforms and signal analysis to be done, so this should be relevant to sci.physics. I'd be most surprised if any commercial CD used MP3 or any other lossy format at any stage of its production. Indeed they mostly use a rather higher sampling rate etc in production to allow easier signal processing - eq and compression, etc. But non of that stops the end product sounding crap if that's what the record company wants. And they frequently do. -- *TEAMWORK...means never having to take all the blame yourself * Dave Plowman London SW To e-mail, change noise into sound. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
"Dave" wrote in message oups.com... Snipped I have listened to plenty of CD (about 650), so I think I can tell a good recording from a bad one. There may be problems of course with quantative measurement, in that the recording could be done to get the measurement high, and it could just sound clinical. The point was that if I thought a CD sounded poor quality I think there should be a computer program to confirm this, instead of just asking someone else. That's like asking if there's a computer program to confirm a wine is of poor quality, or a piece of art work is of poor quality. Quality is subjective, is a composite of many individual factors and can't be reduced to a number. A computer program (or manual instruments) can analyse the performance of a piece of music, and give you numbers for dynamic range, frequency range and by analysing the gaps between music, the background noise level. It can't then tell you whether this is "good" or "bad" as these are value judgements. As to your OP, I think you are asking for a piece of (free) software that will analyse for any "footprint" left behind by MP3 compression. I have never come across any such software, free or otherwise, nor do I know of any reliable way of telling subjectively that something has been (or even is) MP3 processed, if the bit rate used is high enough. Others have mentioned the infuriating habit today of removing any vestige of dynamic range from modern mastered CDs, then clipping the result, all in an attempt to get maximum loudness. I previously posted that the Daily Mail even, ran an article a week or two ago highlighting this trend. However, it is not all the fault of the producers foisting their ideas on the poor artists, even some artists insist that their CDs are mastered as loud as possible, as a part of their "sound". Lily Allen was mentioned by name. This, I think, is much more likely to be the reason for dissatisfaction with recently mastered CDs than any (unlikely) possibility that MP3 was involved. As a consequence, I now don't buy any CD that was mastered (or remastered) in the past 10-12 years. S. -- http://audiopages.googlepages.com |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
"Dave" wrote in message oups.com... On 23 Jun, 06:44, "Colin B." wrote: In rec.audio.tech Dave wrote: I have been disappointed with the audio quality of some CDs I have bought recently. Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. Unless these are pirated copies, the answer is most likely not. That's too much pointless effort for commercial studios to go through. The answer is much more mundane: Most recording sucks. Maybe I should retrain when I get to 50 because by then all younger sound engineers will have grown up with MP3s and not have a clue what decent audio sounds like. This is all too true. How many young "sound engineers" today ever get to mike up a drum kit, or piano these days. How many ever get to record even a string quartet let alone a full symphony orchestra with a crossed pair of mics? They may do it as part of a college course, but then never get to practice once they get out in the world. S. -- http://audiopages.googlepages.com |
How can I tell music has been an MP3? Quantitative Measurementof Fidelity
Dave wrote:
I have been disappointed with the audio quality of some CDs I have bought recently. Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. To get a good measure I'd expect some Fourier transforms and signal analysis to be done, so this should be relevant to sci.physics. Which CDs? Perhaps someone else has them and can comment. -- Eiron. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
"Serge Auckland" wrote in message
... As to your OP, I think you are asking for a piece of (free) software that will analyse for any "footprint" left behind by MP3 compression. I have never come across any such software, free or otherwise Well, you could look for a 15.8kHz hard bandlimit on the audio using the frequency analyzer in a DAW. That would indicate the likelihood that a 128kbps .mp3 was part of the chain. It's still pretty unlikely, though, unless the recording is something like a live gig issued by the band itself, perhaps from a portable .mp3 recorder. Not impossible, though. Hey, I once co-produced and mastered an album from a hodgepodge of sources, and one track on it was from MiniDisc, which uses perceptual-coding algorithms not too conceptually different from those in the .mp3 format. It's Art Thieme's "The Older I Get, The Better I Was" on Waterbug. I'd be surprised if someone can tell me which track it was by ear (no cheating and looking at the liner notes!) Peace, Paul |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
"Dave" wrote in message
oups.com I have been disappointed with the audio quality of some CDs I have bought recently. Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) I have my suspicious that some may have been stored an MP3s and then "unripped" in the factory. So how can I tell for certain if my CD has been an MP3, or other lossy format? I'd hope mp3 storage would leave different markers than the original tape, for example. Spectal analysis can give strong evidence. Most MP3 files show signs of a brickwall low pass filter the audio band - sometimes as low as 15 KHz or less. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
"Dave" wrote in message oups.com... I have been disappointed with the audio quality of some CDs I have bought recently. No surprise there, but let's not get into all of that..... Is there a free program I can use to get an accepted measurement of fidelity? (like a signal to noise ratio) So you can do what - take any disks back to the shop for a refund if a computer tells you the 'fidelity factor' is below a certain figure whether you actually *liked* the sound or not....??? |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
"Colin B." wrote I'd suggest that this isn't a recent phenomenon. I've got plenty of pop vinyl from the 1970s and 1980s that has roughly no dynamics. Yep, you bought it so *they* kept on supplying it - same thing's happening today, apparently. Where's the problem? Making crap sound louder on the radio at the complete expense of quality is decades old. Compressed audio like 'Classic FM' on a car radio works very well, actually.... |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
"Serge Auckland" wrote in message ... "Dave" wrote The point was that if I thought a CD sounded poor quality I think there should be a computer program to confirm this, instead of just asking someone else. That's like asking if there's a computer program to confirm a wine is of poor quality, or a piece of art work is of poor quality. Quality is subjective, is a composite of many individual factors and can't be reduced to a number. A computer program (or manual instruments) can analyse the performance of a piece of music, and give you numbers for dynamic range, frequency range and by analysing the gaps between music, the background noise level. It can't then tell you whether this is "good" or "bad" as these are value judgements. The clue to the answer to this sort of question is usually in the question itself. Plenty of people seem need to see figures or a graph to answer the 'am I enjoying/did I enjoy that?' question - there's no shortage of that in here.... Me? I wouldn't be without the Deviation Meter on me chooner - otherwise, how TF would I know if the music was sounding any good (or not)..?? ;-) |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
On Sat, 23 Jun 2007 04:53:54 -0400, Dave Plowman (News) wrote
(in article ): In article , Colin B. wrote: There's a far more mundane explanation. Recent music distribution, including CDs, have suffered from an industry-wide of sever over compression, limiting and clipping, as an endemic result of the mastering process. I'd suggest that this isn't a recent phenomenon. I've got plenty of pop vinyl from the 1970s and 1980s that has roughly no dynamics. Making crap sound louder on the radio at the complete expense of quality is decades old. There's a difference in how this was acheived, though. In older days it was through the arrangement of the music and studio recording practices. The Phil Spector 'wall of sound' for example. These days it's done using largely automatic processors after the studio recording is signed off. Similar to the types used for processing radio at the transmitters. I'll respectfully disgree, Dave. Colin's right. In the US, anyway. In our local songwriters ass'n compilation CD, two years ago, we had several entries that were mp3 and NOT particularly well done. We let it go in the name of art. (Not this year though.) Lots of artifacts and reduced bandwidth that's what you look (listen) for. Try MP3ing them and see if they don't fall apart even more precipitously relative to normal wav files. Regards, Ty Ford --Audio Equipment Reviews Audio Production Services Acting and Voiceover Demos http://www.tyford.com Guitar player?:http://www.youtube.com/watch?v=4RZJ9MptZmU |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
On Sat, 23 Jun 2007 07:13:28 -0400, Keith G wrote
(in article ): "Colin B." wrote I'd suggest that this isn't a recent phenomenon. I've got plenty of pop vinyl from the 1970s and 1980s that has roughly no dynamics. Yep, you bought it so *they* kept on supplying it - same thing's happening today, apparently. Where's the problem? Making crap sound louder on the radio at the complete expense of quality is decades old. Compressed audio like 'Classic FM' on a car radio works very well, actually.... Not so well when they play MP3 versus CD cuts. Locally, the oldies station WZBA has enough crunch on their MP3s that I can't really crank a CCR tune as loud as I want in the car because the distortion stops me. That's just a buzz kill. (could be another problem in their audio chain, but I don't think so.) Regards, Ty Forf --Audio Equipment Reviews Audio Production Services Acting and Voiceover Demos http://www.tyford.com Guitar player?:http://www.youtube.com/watch?v=4RZJ9MptZmU |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
In article ,
Keith G wrote: Making crap sound louder on the radio at the complete expense of quality is decades old. Compressed audio like 'Classic FM' on a car radio works very well, actually.... Transmitting material deliberately tweaked for a poor listening environment is rather a two edged sword, though. The car radio could have a compressor built in if that's the sound you want rather than inflicting it on all listeners. Indeed part of the spec of DAB included such a device although I've not known it be implemented. My car radio will alter the level taking into account background noise, though. And eq the speakers using the same microphone as sensor - if you want. Haven't tried either yet as the mic isn't supplied as standard. -- *Ah, I see the f**k-up fairy has visited us again Dave Plowman London SW To e-mail, change noise into sound. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
On Fri, 22 Jun 2007 21:58:27 -0400, Dave wrote
(in article . com): I have been disappointed with the audio quality of some CDs I have bought recently. This has been discussed many times in the recent past. Note that far and away the prime suspect is hyper-compression (compression of the audio levels, NOT data compression of the signal stream.) On the indie market, it's also because the recording talent too frequently can't tell the difference between "Ouch" and "Nice." Cheap mic and preamp choices and not understanding how good audio is made has been as devastating to the quality of audio. You need good people who can make better choices. That's the downside to the democratization of the technology. When ANYONE can afford to do it, that's what you get. I now shoot and edit video for a part of my living. I'm sure some DPs would scorn my work. That's fine. I'm learning and I'll get better. Gotta' nice handheld piece shot last week for singer/songwriter friend Randall Williams. He saw mine and wanted something up on YouTube. You can see/hear it at: http://www.youtube.com/watch?v=sDjKgmMydF4 Regards, Ty Ford --Audio Equipment Reviews Audio Production Services Acting and Voiceover Demos http://www.tyford.com Guitar player?:http://www.youtube.com/watch?v=4RZJ9MptZmU |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
"Paul Stamler" wrote in message ... "Serge Auckland" wrote in message ... As to your OP, I think you are asking for a piece of (free) software that will analyse for any "footprint" left behind by MP3 compression. I have never come across any such software, free or otherwise Well, you could look for a 15.8kHz hard bandlimit on the audio using the frequency analyzer in a DAW. That would indicate the likelihood that a 128kbps .mp3 was part of the chain. It's still pretty unlikely, though, unless the recording is something like a live gig issued by the band itself, perhaps from a portable .mp3 recorder. A hard bandlimit may indicate the possibility of a 128k MP3, but band-limiting can indicate also that a lower sample rate was used:- 32k sample rate was regularly used in the past for ISDN audio transfers, if the intended outlet was FM transmission. Higher bit-rate MP3 would not necessarily have the band-limiting except the normal anti-aliasing filter common to all PCM digital audio. Not impossible, though. Hey, I once co-produced and mastered an album from a hodgepodge of sources, and one track on it was from MiniDisc, which uses perceptual-coding algorithms not too conceptually different from those in the .mp3 format. It's Art Thieme's "The Older I Get, The Better I Was" on Waterbug. I'd be surprised if someone can tell me which track it was by ear (no cheating and looking at the liner notes!) Peace, Paul And some albums were recorded on Tascam Portastudios (4 track analogue cassette), which, arguably, sound a lot worse than MP3 at higher bit rates, domestic reel-reel machines and other sources. S http://audiopages.googlepages.com |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
On Sat, 23 Jun 2007 13:19:57 +0100, "Dave Plowman (News)"
wrote: In article , Keith G wrote: Making crap sound louder on the radio at the complete expense of quality is decades old. Compressed audio like 'Classic FM' on a car radio works very well, actually.... Transmitting material deliberately tweaked for a poor listening environment is rather a two edged sword, though. The car radio could have a compressor built in if that's the sound you want rather than inflicting it on all listeners. Indeed part of the spec of DAB included such a device although I've not known it be implemented. It is implemented on my Arcam DAB receiver. Problem is that it is in my home, and I don't need to use it there. d My car radio will alter the level taking into account background noise, though. And eq the speakers using the same microphone as sensor - if you want. Haven't tried either yet as the mic isn't supplied as standard. It wouldn't work if it were fitted. It would equalise to where the mic is, not where you are, and they will have vastly different frequency response errors, particularly in a car. d -- Pearce Consulting http://www.pearce.uk.com |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
"Ty Ford" wrote in message . .. On Sat, 23 Jun 2007 07:13:28 -0400, Keith G wrote (in article ): "Colin B." wrote I'd suggest that this isn't a recent phenomenon. I've got plenty of pop vinyl from the 1970s and 1980s that has roughly no dynamics. Yep, you bought it so *they* kept on supplying it - same thing's happening today, apparently. Where's the problem? Making crap sound louder on the radio at the complete expense of quality is decades old. Compressed audio like 'Classic FM' on a car radio works very well, actually.... Not so well when they play MP3 versus CD cuts. Locally, the oldies station WZBA has enough crunch on their MP3s that I can't really crank a CCR tune as loud as I want in the car because the distortion stops me. That's just a buzz kill. (could be another problem in their audio chain, but I don't think so.) Regards, Ty Forf --Audio Equipment Reviews Audio Production Services Acting and Voiceover Demos http://www.tyford.com Guitar player?:http://www.youtube.com/watch?v=4RZJ9MptZmU Maybe we should be grateful that here in the UK, the BBC and our larger commercial stations won't allow the use of MP2/3 or MiniDisc source material except in unusual circumstances. As far as I know, GCap (GWR and Capital Groups) and the BBC's hard-disc playout systems are all linear, as are the studio-transmitter links. Whilst they do have very heavy audio compression in the transmission processor, the FM signal stays linear from CD through to FM transmitter. The reason for this is that the same signal is used for the DSat and DAB feeds, and they found that multiple codings gave unacceptable results on DAB, especially at the low bit rates currently used. S. -- http://audiopages.googlepages.com |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
In article ,
Ty Ford wrote: There's a difference in how this was acheived, though. In older days it was through the arrangement of the music and studio recording practices. The Phil Spector 'wall of sound' for example. These days it's done using largely automatic processors after the studio recording is signed off. Similar to the types used for processing radio at the transmitters. I'll respectfully disgree, Dave. Colin's right. In the US, anyway. In our local songwriters ass'n compilation CD, two years ago, we had several entries that were mp3 and NOT particularly well done. We let it go in the name of art. (Not this year though.) I'm not quite sure what that has to do with commercial recordings? Lots of artifacts and reduced bandwidth that's what you look (listen) for. Try MP3ing them and see if they don't fall apart even more precipitously relative to normal wav files. -- *Real men don't waste their hormones growing hair Dave Plowman London SW To e-mail, change noise into sound. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
In article , Serge Auckland
wrote: Others have mentioned the infuriating habit today of removing any vestige of dynamic range from modern mastered CDs, then clipping the result, all in an attempt to get maximum loudness. I previously posted that the Daily Mail even, ran an article a week or two ago highlighting this trend. ahem There is an article related to this in the latest issue of 'Hi Fi News', cover dated August 2007. Clipping and level compression aren't the only manifestations of this problem... Slainte, Jim -- Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
In article ,
Don Pearce wrote: Transmitting material deliberately tweaked for a poor listening environment is rather a two edged sword, though. The car radio could have a compressor built in if that's the sound you want rather than inflicting it on all listeners. Indeed part of the spec of DAB included such a device although I've not known it be implemented. It is implemented on my Arcam DAB receiver. Problem is that it is in my home, and I don't need to use it there. Right. How well does it work, out of interest? My car radio will alter the level taking into account background noise, though. And eq the speakers using the same microphone as sensor - if you want. Haven't tried either yet as the mic isn't supplied as standard. It wouldn't work if it were fitted. It would equalise to where the mic is, not where you are, and they will have vastly different frequency response errors, particularly in a car. The idea is you put the mic where your head is when doing the auto eq then save the settings. But you aren't then forced to use them - it will store several different settings which may be manually set and recalled. But like all such things I've settled on flat with a small amount of LF lift to counteract tyre rumble etc. -- *Generally speaking, you aren't learning much if your lips are moving.* Dave Plowman London SW To e-mail, change noise into sound. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
On Sat, 23 Jun 2007 14:45:41 +0100, "Dave Plowman (News)"
wrote: In article , Don Pearce wrote: Transmitting material deliberately tweaked for a poor listening environment is rather a two edged sword, though. The car radio could have a compressor built in if that's the sound you want rather than inflicting it on all listeners. Indeed part of the spec of DAB included such a device although I've not known it be implemented. It is implemented on my Arcam DAB receiver. Problem is that it is in my home, and I don't need to use it there. Right. How well does it work, out of interest? Quite well, I would say. I tried the radio in the laundry room to see how it would cope with the noise of the tumble drier, and it made a pretty good job of staying audible. My car radio will alter the level taking into account background noise, though. And eq the speakers using the same microphone as sensor - if you want. Haven't tried either yet as the mic isn't supplied as standard. It wouldn't work if it were fitted. It would equalise to where the mic is, not where you are, and they will have vastly different frequency response errors, particularly in a car. The idea is you put the mic where your head is when doing the auto eq then save the settings. But you aren't then forced to use them - it will store several different settings which may be manually set and recalled. But like all such things I've settled on flat with a small amount of LF lift to counteract tyre rumble etc. Ah - ok. I thought maybe it was some fixed position thing you clipped on a sun visor, or something. d -- Pearce Consulting http://www.pearce.uk.com |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
Ty Ford wrote in :
On the indie market, it's also because the recording talent too frequently can't tell the difference between "Ouch" and "Nice." Funny you should say that ... I now shoot and edit video for a part of my living. Gotta' nice handheld piece shot last week This isn't what I'd call "nice," really not. I didn't sit through the whole piece though, because your swaying all over the place was too annoying to watch. So, yeah, some people obviously can't tell the difference between "Ouch" and "Nice." m |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
In article , Don Pearce
wrote: On Sat, 23 Jun 2007 14:45:41 +0100, "Dave Plowman (News)" wrote: In article , Don Pearce wrote: Transmitting material deliberately tweaked for a poor listening environment is rather a two edged sword, though. The car radio could have a compressor built in if that's the sound you want rather than inflicting it on all listeners. Indeed part of the spec of DAB included such a device although I've not known it be implemented. It is implemented on my Arcam DAB receiver. Problem is that it is in my home, and I don't need to use it there. Right. How well does it work, out of interest? Quite well, I would say. I tried the radio in the laundry room to see how it would cope with the noise of the tumble drier, and it made a pretty good job of staying audible. Are you referring to the 'Dynamic Range Control' system of DAB? If so, which stations are you referring to above? My understanding is that DRC is nominally a common factor for DAB receivers, but I don't which (if any) broadcasters actually use it. Slainte, Jim -- Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
On 2007-06-23, Markus Mietling wrote:
Ty Ford wrote in : On the indie market, it's also because the recording talent too frequently can't tell the difference between "Ouch" and "Nice." Funny you should say that ... I now shoot and edit video for a part of my living. Gotta' nice handheld piece shot last week This isn't what I'd call "nice," really not. I didn't sit through the whole piece though, because your swaying all over the place was too annoying to watch. So, yeah, some people obviously can't tell the difference between "Ouch" and "Nice." The sound was nice, though, as those things go. 8-) -- Mickey Fast, reliable, cheap. Pick two and we'll talk. -- unknown ----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
In article ,
Don Pearce wrote: The idea is you put the mic where your head is when doing the auto eq then save the settings. But you aren't then forced to use them - it will store several different settings which may be manually set and recalled. But like all such things I've settled on flat with a small amount of LF lift to counteract tyre rumble etc. Ah - ok. I thought maybe it was some fixed position thing you clipped on a sun visor, or something. I've not really read the instructions as the manual is like a telephone directory, but that might be a decent place when using it for simply altering the level according to the background noise - it can use the same mic. -- *Sometimes I wake up grumpy; Other times I let him sleep. Dave Plowman London SW To e-mail, change noise into sound. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
In article ,
Ty Ford wrote: Gotta' nice handheld piece shot last week for singer/songwriter friend Randall Williams. He saw mine and wanted something up on YouTube. You can see/hear it at: http://www.youtube.com/watch?v=sDjKgmMydF4 'Nice' hand held? To me, hand held means slight movement to simulate what the eye sees. Yours appears to be moving the camera for the sake of it. I was taught any camera moves that grab the eye are bad moves - it suggests the subject material is too boring on its own. Of course such techniques are all too common these days and obviously loved by meja types who have no interest in presenting a subject intelligently. -- *(on a baby-size shirt) "Party -- my crib -- two a.m Dave Plowman London SW To e-mail, change noise into sound. |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
"Ty Ford" wrote in message . .. On Sat, 23 Jun 2007 07:13:28 -0400, Keith G wrote (in article ): "Colin B." wrote I'd suggest that this isn't a recent phenomenon. I've got plenty of pop vinyl from the 1970s and 1980s that has roughly no dynamics. Yep, you bought it so *they* kept on supplying it - same thing's happening today, apparently. Where's the problem? Making crap sound louder on the radio at the complete expense of quality is decades old. Compressed audio like 'Classic FM' on a car radio works very well, actually.... Not so well when they play MP3 versus CD cuts. Locally, the oldies station WZBA has enough crunch on their MP3s that I can't really crank a CCR tune as loud as I want in the car because the distortion stops me. That's just a buzz kill. (could be another problem in their audio chain, but I don't think so.) Once again, I didn't spot the crossposting!! I should have said: In the UK, Classic FM don't sound too bad on the car radio!! (I see others have said that we don't broadcast from lo-res MP3s in the UK??) |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
In article , Ty Ford
writes On Sat, 23 Jun 2007 07:13:28 -0400, Keith G wrote (in article ): "Colin B." wrote I'd suggest that this isn't a recent phenomenon. I've got plenty of pop vinyl from the 1970s and 1980s that has roughly no dynamics. Yep, you bought it so *they* kept on supplying it - same thing's happening today, apparently. Where's the problem? Making crap sound louder on the radio at the complete expense of quality is decades old. Compressed audio like 'Classic FM' on a car radio works very well, actually.... Not so well when they play MP3 versus CD cuts. Locally, the oldies station WZBA has enough crunch on their MP3s that I can't really crank a CCR tune as loud as I want in the car because the distortion stops me. That's just a buzz kill. (could be another problem in their audio chain, but I don't think so.) The problem with radio processing is that MP3's and other data reduced sources do not process very well. Its akin to taking a 2 M photo and expanding it up and then comparing it to a 10 M Least radio 3 use linear PCM for their source audio, some other broadcasters don't see it that way!. And Klassick 'eff em is too far processed anyway!.. -- Tony Sayer |
How can I tell music has been an MP3? Quantitative Measurement of Fidelity
In article .com, Dave
writes On 23 Jun, 03:43, "Richard Crowley" wrote: "Dave" wrote ... , "Richard Crowley" wrote: 1) SNR is not "an accepted measurement of fidelity" 2) There is no specific "accepted measurement of fidelity" "Fidelity" is a combination of many things. Some subjective. 3) It would be difficult-to-impossible to actually meausre SNR on a commercial CD because of the way they are mastered. (i.e. there is no "baseline" because it is usually muted) Have there been no bright PhD students sponsored by the music industry, or are they too busy with their revenue stream? The noise is what is not the notes. For a symphony you have an idea of what the notes should be, because you have the sheet music, and you know what a violin, flute etc should sound like. You may be able to measure something more because that is what the brain does. That is just impossibly simplistic. There is a great deal of stuff "between the notes" besides noise. Have you done much recording yourself? It doesn't sound as complicated as fusion, and that is having billions spent on it. Besides I thought banks and defence liked graduates with in-depth signal analysis experience. I have listened to plenty of CD (about 650), so I think I can tell a good recording from a bad one. There may be problems of course with quantative measurement, in that the recording could be done to get the measurement high, and it could just sound clinical. The point was that if I thought a CD sounded poor quality I think there should be a computer program to confirm this, instead of just asking someone else. Oddly enough I've been out an about to some live events recently and the sound there and at home ..I always want to twiddle something to make it sound how I think it should be rather then what it is;) -- Tony Sayer |
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