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Dave Dave is offline
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Default 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.

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Default 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.

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Default 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.
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Ty Ford Ty Ford is offline
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Default 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



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Default 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.
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Default 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....


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Default 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

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Default 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


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Default 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??)






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Default 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


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Default 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.
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Don Pearce Don Pearce is offline
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Default 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
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Default How can I tell music has been an MP3? Quantitative Measurement of Fidelity


"Keith G" wrote


Compressed audio like 'Classic FM' on a car radio works very well,
actually....



Last night some solo piano pieces were particularly good on Carsick FM
FM - very acceptable.

(I couldn't compare with R3 because there was only some tiny little
voices muttering away throughout my entire journey...)


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Default How can I tell music has been an MP3? Quantitative Measurement of Fidelity

In rec.audio.tech Keith G wrote:

"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?


Yep. Some of it I did, and when I was under 12 years old, I didn't notice
the difference. That doesn't mean that it's their moral perogative to
contiue producing crap.

Much of it I've picked up recently, for $0.50 per album at garage sales
and used record shops. On a whim, I got Kim Carnes' "Mistaken Identity"
tossed in when I bought a turntable a while back. Thing is about 0.03db
between the loudest and quietest passages. Horrible to listen to.

Compressed audio like 'Classic FM' on a car radio works very well,
actually....


True, car audio is a different beast in many ways. Many of my favorite
albums (on CD, that is) don't come with me in the car, because the volume
I need to listen to 70% of them makes the remaining 30% painfully loud.
But they sound brilliant at home.

Colin


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"Colin B." wrote in message
...
In rec.audio.tech Keith G wrote:


I did, but it was a long time ago...



"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?


Yep. Some of it I did, and when I was under 12 years old, I didn't
notice
the difference. That doesn't mean that it's their moral perogative to
contiue producing crap.



The equation is a simple one - if crap is bought, then crap will be
produced...


Much of it I've picked up recently, for $0.50 per album at garage
sales
and used record shops. On a whim, I got Kim Carnes' "Mistaken
Identity"
tossed in when I bought a turntable a while back. Thing is about
0.03db
between the loudest and quietest passages. Horrible to listen to.



The days of good 'threefers' and 'forfers' (charity shop 'bundled vinyl'
offers) are gone. Worthwhile vinyl is a few quid a slice now and no
longer peanuts off Fleabay, what with the postage, these days...



Compressed audio like 'Classic FM' on a car radio works very well,
actually....


True, car audio is a different beast in many ways. Many of my favorite
albums (on CD, that is) don't come with me in the car, because the
volume
I need to listen to 70% of them makes the remaining 30% painfully
loud.



That's a *ding*....

:-)



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Default 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. Making crap
sound louder on the radio at the complete expense of quality is decades old.


That vinyl was pumped to hell and back with massive compression, BUT it
wasn't aggressively limited as well, because aggressive limiting didn't
really improve loudness on vinyl much.

Today with the CD there is a hard limit for level, and so you hear a lot of
heavy peak limiting today. That's more destructive to the overall sound.
The combination of the two is an absolute killer.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
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Default 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.


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Default 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?

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Default 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.




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Default 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.

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Serge Auckland Serge Auckland is offline
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Default 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


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tony sayer tony sayer is offline
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Default 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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Scott Dorsey Scott Dorsey is offline
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Default How can I tell music has been an MP3? Quantitative Measurement of Fidelity

"Dave" wrote ...

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.


"Music is the space between the notes."
-- Franz Liszt


--
"C'est un Nagra. C'est suisse, et tres, tres precis."
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Richard Kuschel Richard Kuschel is offline
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Default How can I tell music has been an MP3? Quantitative Measurement of Fidelity

On Jun 26, 7:54 am, (Scott Dorsey) wrote:
"Dave" wrote ...



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.


"Music is the space between the notes."
-- Franz Liszt

--
"C'est un Nagra. C'est suisse, et tres, tres precis."




I thought that "Music is the space between the notes." was John Cage,
but more research seems to attribute it to Claude Debussy. I would
imagine that it has been paraphrased a few times by other people.



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Ty Ford Ty Ford is offline
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Default 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

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Markus Mietling Markus Mietling is offline
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Default 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
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Mickey Mickey is offline
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Default 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


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Ty Ford Ty Ford is offline
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Default How can I tell music has been an MP3? Quantitative Measurement of Fidelity

On Sat, 23 Jun 2007 10:18:52 -0400, Markus Mietling wrote
(in article ):

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


Horses and Courses. The client liked it. You must never have seen MTV, or
Homicide- Life On The Street.

Ah! Are you in the UK?

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

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Dave Plowman (News) Dave Plowman (News) is offline
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Default 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.


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Ty Ford Ty Ford is offline
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Default How can I tell music has been an MP3? Quantitative Measurement of Fidelity

On Sat, 23 Jun 2007 12:27:06 -0400, Dave Plowman (News) wrote
(in article ):

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.



"All too common" , I'll take that from anyone in the UK.

Thanks,

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

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Rich[_2_] Rich[_2_] is offline
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Default 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.

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tonewheel tonewheel is offline
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Default How can I tell music has been an MP3? Quantitative Measurement of Fidelity

On 23 Jun, 04:36, Rich wrote:

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.



About 5 years ago I digitised a lot of my old vinyl LP's and burned
them to audio CD-R's. I recorded the output of a turntable through a
RIAA (sp?) filter into a computer soundcard, saved as a huge WAV,
imported into SoundForge, did a bit of click/pop removal, put in
markers to separate the tracks, normalised, saved, then used CoolEdit
2000 batch mode to split the large wavs into individual wavs for each
track, then burned to disk.

Imagine my surprise when one of the resultant CD's came up with the
correct album title and track listing from gracenote....

TWJ

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Schöön Martin Schöön Martin is offline
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Default How can I tell music has been an MP3? Quantitative Measurement of Fidelity

tonewheel writes:


Imagine my surprise when one of the resultant CD's came up with the
correct album title and track listing from gracenote....

A couple of years ago I CDfied a couple of my brother-in-law's
LPs. I still have those tracks on my HD as .wav files and I played
one of them in one of the media players on my computer and it
identified the artist if not the album and track. I was very,
very surprised.

--
Martin Schöön

"Problems worthy of attack
prove their worth by hitting back"
Piet Hein
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Markus Mietling Markus Mietling is offline
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Default How can I tell music has been an MP3? Quantitative Measurement of Fidelity

tonewheel wrote in
.com:

About 5 years ago I digitised a lot of my old vinyl LP's and burned
them to audio CD-R's. I recorded the output of a turntable through a
RIAA (sp?) filter into a computer soundcard, saved as a huge WAV,
imported into SoundForge, did a bit of click/pop removal, put in
markers to separate the tracks, normalised, saved, then used CoolEdit
2000 batch mode to split the large wavs into individual wavs for each
track, then burned to disk.

Imagine my surprise when one of the resultant CD's came up with the
correct album title and track listing from gracenote....


I can imagine your surprise :-)

Interestingly, it was precisely the gracenote database that uncovered
the Joyce Hatto scam in spite of the tracks having been manipulated to
disguise the theft.

Pristine Audio's Andrew Rose still believes [1] that the information had
been deliberately planted. I believed that too, because I thought that
track identification works with md5sum or some similar hash.

Now that I read your story, it seems to me that the gracenote database
must implement some seriously powerful pattern matching technology.
Quite amazing, IMO.

m

[1] see http://www.pristineclassical.com/HattoHoax.html


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Markus Mietling Markus Mietling is offline
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Default How can I tell music has been an MP3? Quantitative Measurement of Fidelity

Markus Mietling wrote in :

Now that I read your story, it seems to me that the gracenote database
must implement some seriously powerful pattern matching technology.


Or maybe not. According to Wikipedia, it's the combination of track
lengths thats used to identify an album; quite bland, actually :-}

m
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Mr.T Mr.T is offline
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Default How can I tell music has been an MP3? Quantitative Measurement of Fidelity


"Markus Mietling" wrote in message
...

Now that I read your story, it seems to me that the gracenote database
must implement some seriously powerful pattern matching technology.
Quite amazing, IMO.


In fact it's because the allocated disk number is seriously simply derived
from track numbers and lengths that it works.
Not so amazing really.

MrT.


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Colin B. Colin B. is offline
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Default 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.

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Default 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.

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Serge Auckland Serge Auckland is offline
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Default 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




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