[Marc Wielage]

On Jun 22, 2007, Dave commented:

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.
------------------------------snip------------------------------

If they're major-label CDs, I'd be floored if they were making CDs from
data-compressed files like MP3s. There's just no reason to do it.

There have been cases where pirated recordings or shared files have been
"up-rezzed" from lossy files, and radio stations have sometimes used lossy
files on air (particularly commercials). I found this on the net:

For some odd reason, there are people who foolishly convert MP3 files to FLAC
(or APE), perhaps in the mistaken belief that it will make the signal "sound"
better. This is the sonic equivalent of taking a 1" square photograph and
blowing it up to 10", believing it will look as good as an original 10"
photograph.

"A shareware Windows program called "AudioChecker" can analyze various kinds
of FLAC, APE, and other lossless files and then intelligently make a guess as
to whether the files are legit or just "uprezed" from an MP3 file, based on
technical factors like frequency response. AudioChecker is available from:

http://www.dester.hu


I haven't used the program, so I can't say for a fact that it works, but MP3
artifacts are very noticeable if you know what to listen for. I don't doubt
you're hearing something bad, but it's possible you may be hearing some other
kinds of distortion in the track.

--MFW

[Earl Kiosterud]

"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.

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.


Dave,

You can, to some extent, find out what the mp3 process does to the audio for yourself. You
could get an audio editor, like Cool Edit (now in Adobe's Audition), and do some recording
yourself. Save the piece as mp3, with different bitrates, reopen it, and you'll get an idea
of what artifacts the lossy compression introduces. Years ago, when mp3 codecs were newer,
the lower bit rates, like 64K, produced a watery sound. I know that's not terribly
descriptive, but it's the best way I can describe it. They seem to be better now. The
low-data-rate streaming internet radio stations have that watery sound. You'll also notice
high-frequency loss at the lower rates. As the bit rate goes up, all that diminishes. Just
for grins, I once took a very clean-sounding piece, and compared an mp3 of it (128K, I think
it was) to the original wav, subtracting one from the other. The result was a very watery
glub-glub sound, though relatively low in amplitude compared to the original.

Regards from Virginia Beach,

Earl Kiosterud

[Dave Plowman (News)]

In article Kxffi.2684$XH5.1402@trndny02,
Karl Uppiano wrote:
Former Beatle, George Harrison said that every generation has its own
"sound", depending on the kind of mixers they used (he probably meant
more than mixers, but I think he referred to mixers specifically). He
made some mention of the sound of Hoagy Charmichael recordings. But
engineering techniques will exploit and/or compensate for the
technology at hand. CDs made from masters originally targeting vinyl
sometimes didn't sound as good as CDs made from masters targeting CDs.

I've got pretty well every Beatles LP and CD, the CDs bought as they came
out, same as the LPs, and in every case (IMHO) the CD sounds miles better
than the LP. Many of which weren't the best of pressings anyway. EMI
weren't *that* careful with their pop stuff. Perhaps the most instant
comparison I could make if you have both is 'Michelle', the last track on
side one of Rubber Soul. On every combination of pressing and playing
equipment I've heard it is quite heavily distorted - but not so on the CD.
I've not had the opportunity to compare the single.

Engineers recording to analog tape at times deliberately overloaded the
tape for specific effects (sometimes providing the illusion of dynamic
range that wasn't actually there). Each generation had its supporters
and detractors, and each cited "solid, factual" evidence to support
their opinions. Audio recording was, and still is, more of an art than
a science.

It was fairly common to overload analogue tape with brass and similar
instruments to give some 'edge' on other than classical recordings.

--
*There are 3 kinds of people: those who can count & those who can't.

Dave Plowman London SW
To e-mail, change noise into sound.

[Ty Ford]

On Sat, 23 Jun 2007 08:42:57 -0400, Serge Auckland wrote
(in article ):

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.

Yes, Serge, I think you should.

I wish there was a law that MADE radio stations here in the US have higher
encoding standards.

Then there's the multiple encode/decodes of XM and Sirius. Do we have any
comments from audiophile XM/Sirius listeners?

Herb Squire(s) did a show and tell at the NY AES a number of years ago
demonstrating the results of multiple, serial compression schemes.

Although compression technology has changed (improved) since then, it's
amazing the see the rabid followers of the HDV video format defend their 384
kbps stereo audio.

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

[Ty Ford]

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

[Ty Ford]

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

[Ty Ford]

On Sat, 23 Jun 2007 16:39:06 -0400, Karl Uppiano wrote
(in article Kxffi.2684$XH5.1402@trndny02):

Former Beatle, George Harrison said that every generation has its own
"sound",

George left the Beatles? Ah, another euphemism for "dead."

Fascinating. I'm collecting them.

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

[Ty Ford]

On Sun, 24 Jun 2007 02:04:17 -0400, Earl Kiosterud wrote
(in article BPnfi.1319$s%.148@trnddc02):
Dave,

You can, to some extent, find out what the mp3 process does to the audio for
yourself. You
could get an audio editor, like Cool Edit (now in Adobe's Audition), and do
some recording
yourself. Save the piece as mp3, with different bitrates, reopen it, and
you'll get an idea
of what artifacts the lossy compression introduces. Years ago, when mp3
codecs were newer,
the lower bit rates, like 64K, produced a watery sound. I know that's not
terribly
descriptive, but it's the best way I can describe it. They seem to be better

now. The
low-data-rate streaming internet radio stations have that watery sound.
You'll also notice
high-frequency loss at the lower rates. As the bit rate goes up, all that
diminishes. Just
for grins, I once took a very clean-sounding piece, and compared an mp3 of it

(128K, I think
it was) to the original wav, subtracting one from the other. The result was
a very watery
glub-glub sound, though relatively low in amplitude compared to the original.

Regards from Virginia Beach,

Earl Kiosterud


No, Earl, that's quite a good description. I hear it first in the cymbals and
other HF info, especially if that info has a lot of stereo content.

I was playing around with iTunes a few years back and clicked on their
"stereo enhance" button before importing CSNY's "Carry On" as an mp3. The
playback sounded like it was coming out of a washing machine.

Without the enhancement, the mp3 audio was better; mp3, but better. So it's
somewhat relative.

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

[Eiron]

Ty Ford wrote:
On Sat, 23 Jun 2007 16:39:06 -0400, Karl Uppiano wrote
(in article Kxffi.2684$XH5.1402@trndny02):

Former Beatle, George Harrison said that every generation has its own
"sound",

George left the Beatles? Ah, another euphemism for "dead."

Fascinating. I'm collecting them.

Here are a couple of which you may not have heard.
http://www.phespirit.info/derekandclive/live_12.htm

--
Eiron.

[Richard Crowley]

"Dave Plowman (News)" wrote ...
I've got pretty well every Beatles LP and CD, the CDs bought as they
came
out, same as the LPs, and in every case (IMHO) the CD sounds miles
better
than the LP. Many of which weren't the best of pressings anyway. EMI
weren't *that* careful with their pop stuff. Perhaps the most instant
comparison I could make if you have both is 'Michelle', the last track
on
side one of Rubber Soul. On every combination of pressing and playing
equipment I've heard it is quite heavily distorted - but not so on the
CD.
I've not had the opportunity to compare the single.

Of course, the closer you get to the center of the LP,
the "slower" the "writing speed" and the poorer the
reproduction. LPs are "CAV" constant angular velocity,
they rotate at 33 1/3 RPM regardless of where you are
reading.

OTOH, CDs are CLV, constant linear velocity. CDs
rotate at ~500 RPM at the begining of the track (in the
center) and only ~200 RPM at the end (the outer edge).

[Dave Plowman (News)]

In article ,
Richard Crowley wrote:
"Dave Plowman (News)" wrote ...
I've got pretty well every Beatles LP and CD, the CDs bought as they
came out, same as the LPs, and in every case (IMHO) the CD sounds
miles better than the LP. Many of which weren't the best of pressings
anyway. EMI weren't *that* careful with their pop stuff. Perhaps the
most instant comparison I could make if you have both is 'Michelle',
the last track on side one of Rubber Soul. On every combination of
pressing and playing equipment I've heard it is quite heavily
distorted - but not so on the CD. I've not had the opportunity to
compare the single.

Of course, the closer you get to the center of the LP,
the "slower" the "writing speed" and the poorer the
reproduction. LPs are "CAV" constant angular velocity,
they rotate at 33 1/3 RPM regardless of where you are
reading.

OTOH, CDs are CLV, constant linear velocity. CDs
rotate at ~500 RPM at the begining of the track (in the
center) and only ~200 RPM at the end (the outer edge).

Absolutely. Which shows the lie that LP sounds 'better' than CD. It's not
even consistent over itself. It's also a design fault given that many
classical pieces have the most demanding audio at the finish - exactly the
point where vinyl is at its worst.

--
*I can see your point, but I still think you're full of ****.

Dave Plowman London SW
To e-mail, change noise into sound.

[Serge Auckland]

"Dave Plowman (News)" wrote in message
...
In article ,
Richard Crowley wrote:
"Dave Plowman (News)" wrote ...
I've got pretty well every Beatles LP and CD, the CDs bought as they
came out, same as the LPs, and in every case (IMHO) the CD sounds
miles better than the LP. Many of which weren't the best of pressings
anyway. EMI weren't *that* careful with their pop stuff. Perhaps the
most instant comparison I could make if you have both is 'Michelle',
the last track on side one of Rubber Soul. On every combination of
pressing and playing equipment I've heard it is quite heavily
distorted - but not so on the CD. I've not had the opportunity to
compare the single.

Of course, the closer you get to the center of the LP,
the "slower" the "writing speed" and the poorer the
reproduction. LPs are "CAV" constant angular velocity,
they rotate at 33 1/3 RPM regardless of where you are
reading.

OTOH, CDs are CLV, constant linear velocity. CDs
rotate at ~500 RPM at the begining of the track (in the
center) and only ~200 RPM at the end (the outer edge).

Absolutely. Which shows the lie that LP sounds 'better' than CD. It's not
even consistent over itself. It's also a design fault given that many
classical pieces have the most demanding audio at the finish - exactly the
point where vinyl is at its worst.

--
*I can see your point, but I still think you're full of ****.

Dave Plowman London SW
To e-mail, change noise into sound.

I've always wondered why first 78s then LPs evolved with the recording from
outside in. It must have been noticed right at the beginning that the
loudest parts of classical music are often at the end, so it would have made
no difference to the operation to have the start at the inner grooves. The
possible problem of the stylus falling off the outside of the record could
easily be solved with a locked groove, or a lip on the outer edge. Even the
even earlier cylinders had a constant velocity.

Funny how some things get done.....

S.

--
http://audiopages.googlepages.com

[Dave Plowman (News)]

In article ,
Serge Auckland wrote:
Absolutely. Which shows the lie that LP sounds 'better' than CD. It's
not even consistent over itself. It's also a design fault given that
many classical pieces have the most demanding audio at the finish -
exactly the point where vinyl is at its worst.

I've always wondered why first 78s then LPs evolved with the recording
from outside in. It must have been noticed right at the beginning that
the loudest parts of classical music are often at the end, so it would
have made no difference to the operation to have the start at the inner
grooves. The possible problem of the stylus falling off the outside of
the record could easily be solved with a locked groove, or a lip on the
outer edge. Even the even earlier cylinders had a constant velocity.

Funny how some things get done.....

Some in house BBC 33 rpm coarse groove records were indeed cut from the
inside out.

--
*Money isn't everything, but it sure keeps the kids in touch.

Dave Plowman London SW
To e-mail, change noise into sound.

[tonewheel]

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

[Anahata]

Serge Auckland wrote:

I've always wondered why first 78s then LPs evolved with the recording from
outside in.

My guess: because it's easier to lower the needle accurately into the
groove that way.

Of course that all went out of the window when discs started being all
dfferent sizes, especially when we had to play 7" discs on a 12"
turntable, and I shouldn't be surprised if that's when those little
hydraulic lifting/lowering levers became popular.

Anahata

[Schöön Martin]

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

[Markus Mietling]

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

[Markus Mietling]

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

[Clifford Nelson]

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.

CBS television news played part of a Beatles song because they were
talking about Paul's divorce. It was in tune. It is slightly out of tune
on the two or three CD versions I have of it. It went through the
optical cable to a Harman Kardon AVR 240 from a cable TV box 48 Khz PCM.

John Lennon answered a question "Why is The Beatles music so popular?",
He said, "We don't know. We really don't know. If we knew we would be
managers."

The Beatles liked the movie "The Girl Can't Help It." starring Jane
Mansfield, about a couple of gangsters who controlled the jukebox
business.

I can't demonstrate how the 30 to 40 year old music was perfectly in
tune years ago to my nephews and nieces. They like the music, but they
will probable never know what all the excitement was about.

Maybe you just have to know who to bribe and how much to pay if you want
to communicate a voice or guitar note that is perfectly in tune to the
public. Maybe MP3, aiff, SACD etc. doesn't make that much difference.

Cliff Nelson

Dry your tears, there's more fun for your ears,
"Forward Into The Past" 2 PM to 5 PM, Sundays,
California time,
http://www.geocities.com/forwardintothepast/
Don't be a square or a blockhead; see:
http://bfi.org/node/574

http://library.wolfram.com/infocente...s=1;search_per
son_id=607

[Scott Dorsey]

Anahata wrote:
Serge Auckland wrote:

I've always wondered why first 78s then LPs evolved with the recording from
outside in.

My guess: because it's easier to lower the needle accurately into the
groove that way.

Also, remember that when you're recording direct to disc, you aren't
always sure when the piece will end precisely. Cutting outside-in means
you have some slack at the end. Cutting inside-out means if the piece
ends early you have wasted the best-sounding part of the record.

Of course that all went out of the window when discs started being all
dfferent sizes, especially when we had to play 7" discs on a 12"
turntable, and I shouldn't be surprised if that's when those little
hydraulic lifting/lowering levers became popular.

Those became popular when cartridges became more delicate in the fifties.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Dave Plowman (News)]

In article ,
Scott Dorsey wrote:
I've always wondered why first 78s then LPs evolved with the
recording from outside in.

My guess: because it's easier to lower the needle accurately into the
groove that way.

Also, remember that when you're recording direct to disc, you aren't
always sure when the piece will end precisely. Cutting outside-in means
you have some slack at the end. Cutting inside-out means if the piece
ends early you have wasted the best-sounding part of the record.

Strange - as this is exactly what the BBC did with direct cut discs before
tape days. They used 33 rpm, but fixed pitch coarse groove.

--
*If you must choose between two evils, pick the one you've never tried before

Dave Plowman London SW
To e-mail, change noise into sound.

[Paul Stamler]

"Serge Auckland" wrote in message
...

I've always wondered why first 78s then LPs evolved with the recording
from
outside in. It must have been noticed right at the beginning that the
loudest parts of classical music are often at the end, so it would have
made
no difference to the operation to have the start at the inner grooves. The
possible problem of the stylus falling off the outside of the record could
easily be solved with a locked groove, or a lip on the outer edge. Even
the
even earlier cylinders had a constant velocity.

Funny how some things get done.....

Some labels, including Pathe, did put out center-start records during the 78
era. Some radio transcriptions were done that way, too. And radio
transcriptions of long shows were sometimes done alternating center-start
and rim-start, so there would be no jarring change in sound quality as the
operator switched from disc to disc.

Peace,
Paul

[Scott Dorsey]

Dave Plowman (News) wrote:
In article ,
Scott Dorsey wrote:
I've always wondered why first 78s then LPs evolved with the
recording from outside in.

My guess: because it's easier to lower the needle accurately into the
groove that way.

Also, remember that when you're recording direct to disc, you aren't
always sure when the piece will end precisely. Cutting outside-in means
you have some slack at the end. Cutting inside-out means if the piece
ends early you have wasted the best-sounding part of the record.

Strange - as this is exactly what the BBC did with direct cut discs before
tape days. They used 33 rpm, but fixed pitch coarse groove.

Yes, but they had to cut inside-out because they didn't have effective
chip-chasers. Most US broadcasters did the same thing.

Note that for broadcast applications, you usually CAN predict when everything
will end, down to the second.
--scott

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

[Serge Auckland]

"Scott Dorsey" wrote in message
...
Dave Plowman (News) wrote:
In article ,
Scott Dorsey wrote:
I've always wondered why first 78s then LPs evolved with the
recording from outside in.

My guess: because it's easier to lower the needle accurately into the
groove that way.

Also, remember that when you're recording direct to disc, you aren't
always sure when the piece will end precisely. Cutting outside-in means
you have some slack at the end. Cutting inside-out means if the piece
ends early you have wasted the best-sounding part of the record.

Strange - as this is exactly what the BBC did with direct cut discs before
tape days. They used 33 rpm, but fixed pitch coarse groove.

Yes, but they had to cut inside-out because they didn't have effective
chip-chasers. Most US broadcasters did the same thing.


Scott, what's a chip-chaser?

S.

--
http://audiopages.googlepages.com

[Kevin T]

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.

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.

Opticom / psytechnics have a PEAQ based tool for media filesYMMV I
know there PESQ tool works well both not cheap.
Rightmark makes one cheap / free ask Arny K about it I Have no
experience with it

Kevin T

[Andrew Virnuls]

"Eiron" wrote in message
...
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.

I was wondering why no-one's named any examples, so I'll give one - "Stars
of CCTV" by Hard-Fi.

My first thought on hearing that was that it had been stored using lossy
compression at some point - it suffers from that same metallic, Daleky
quality that blights DAB.

Andrew

[tony sayer]

In article , Andrew
Virnuls writes
"Eiron" wrote in message
...
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.

I was wondering why no-one's named any examples, so I'll give one - "Stars
of CCTV" by Hard-Fi.

My first thought on hearing that was that it had been stored using lossy
compression at some point - it suffers from that same metallic, Daleky
quality that blights DAB.

Noooo!, you can't say that in here!, your have Dave the DAB policeman
along quicker then the word lightning conjures up w_tom .

With Jim his new deputy;-))

Andrew



--
Tony Sayer

[Dave Plowman (News)]

In article ,
Scott Dorsey wrote:
Strange - as this is exactly what the BBC did with direct cut discs
before tape days. They used 33 rpm, but fixed pitch coarse groove.

Yes, but they had to cut inside-out because they didn't have effective
chip-chasers. Most US broadcasters did the same thing.

Chip chaser? What that - not a term I'm familiar with.

Note that for broadcast applications, you usually CAN predict when
everything will end, down to the second.

Didn't matter as it was common practice to overlap recordings using two
cutters so any length of prog could be recorded. But in those days progs
were recorded mainly for archive purposes rather than as a production tool
- the vast majority were live.

And in any case a 33rpm coarse groove disc didn't last long enough for
most progs - IIRC about 15 minutes.

--
*If love is blind, why is lingerie so popular?

Dave Plowman London SW
To e-mail, change noise into sound.

[Dave Plowman (News)]

In article ,
Paul Stamler wrote:
Some labels, including Pathe, did put out center-start records during
the 78 era.

Some radio transcriptions were done that way, too. And radio
transcriptions of long shows were sometimes done alternating
center-start and rim-start, so there would be no jarring change in sound
quality as the operator switched from disc to disc.

Interesting. Makes sense but never seen those. Of course it was before
even my time in broadcasting.

--
*If you think this van is dirty, you should try having sex with the driver*

Dave Plowman London SW
To e-mail, change noise into sound.

[Scott Dorsey]

Dave Plowman (News) wrote:
In article ,
Scott Dorsey wrote:
Strange - as this is exactly what the BBC did with direct cut discs
before tape days. They used 33 rpm, but fixed pitch coarse groove.

Yes, but they had to cut inside-out because they didn't have effective
chip-chasers. Most US broadcasters did the same thing.

Chip chaser? What that - not a term I'm familiar with.

Okay, when you cut a lacquer, it displaces some material, and that material
is called chip. The chip tends to curl inward toward the center of the
record. If you cut inside-out, this is a non-issue, but if you cut
outside-in, the stylus will run over its own chip unless you have a vacuum
device or a brush to sweep it away.

Today on modern lathes we have vacuum devices, and the chip is less prone
to break up and fragment because of the hot-stylus system too.

Note that for broadcast applications, you usually CAN predict when
everything will end, down to the second.

Didn't matter as it was common practice to overlap recordings using two
cutters so any length of prog could be recorded. But in those days progs
were recorded mainly for archive purposes rather than as a production tool
- the vast majority were live.

Right.

And in any case a 33rpm coarse groove disc didn't last long enough for
most progs - IIRC about 15 minutes.

That's why RCA made cutting assemblies for 16" discs. Complete with nasty
horrors like automatic diameter equalization...
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[dizzy]

Marc Wielage wrote:

For some odd reason, there are people who foolishly convert MP3 files to FLAC
(or APE), perhaps in the mistaken belief that it will make the signal "sound"
better.

Sounds like those who buy "tubed" CD players, thinking that the one
tube stage at the player's output will somehow "fix" all the "harm"
done to the signal by all the solid-state stuff.

[Mr.T]

"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.

[Mr.T]

"Paul Stamler" wrote in message
news
Some labels, including Pathe, did put out center-start records during the
78
era. Some radio transcriptions were done that way, too. And radio
transcriptions of long shows were sometimes done alternating center-start
and rim-start, so there would be no jarring change in sound quality as the
operator switched from disc to disc.

I can just imagine that operator sometimes got confused which way was next
then :-)
Even if they are well marked, it's surely a recipe for disaster.

MrT.

[Keith G]

"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...)

[Keith G]

"Mr.T" MrT@home wrote in message
u...

"Paul Stamler" wrote in message
news
Some labels, including Pathe, did put out center-start records during
the
78
era. Some radio transcriptions were done that way, too. And radio
transcriptions of long shows were sometimes done alternating
center-start
and rim-start, so there would be no jarring change in sound quality
as the
operator switched from disc to disc.

I can just imagine that operator sometimes got confused which way was
next
then :-)
Even if they are well marked, it's surely a recipe for disaster.


Not as confusing as numbering 2-disc sets of LPs 1/4 and 2/3 for public
performance - where the playing order goes/went as follows:

Stack the albums with sides in this order from the top: 1/4, 3/2

Play Side 1, flip both discs together

Play Side 2, flip top disc only

Play Side 3, remove top disc

Play Side 4, remove disc, take bow, bring up house lights....

[Don Pearce]

On Tue, 26 Jun 2007 11:43:01 +0100, "Keith G"
wrote:


"Mr.T" MrT@home wrote in message
. au...

"Paul Stamler" wrote in message
news
Some labels, including Pathe, did put out center-start records during
the
78
era. Some radio transcriptions were done that way, too. And radio
transcriptions of long shows were sometimes done alternating
center-start
and rim-start, so there would be no jarring change in sound quality
as the
operator switched from disc to disc.

I can just imagine that operator sometimes got confused which way was
next
then :-)
Even if they are well marked, it's surely a recipe for disaster.


Not as confusing as numbering 2-disc sets of LPs 1/4 and 2/3 for public
performance - where the playing order goes/went as follows:

Stack the albums with sides in this order from the top: 1/4, 3/2

Play Side 1, flip both discs together

Play Side 2, flip top disc only

Play Side 3, remove top disc

Play Side 4, remove disc, take bow, bring up house lights....




Or for preference, have two decks, then: Play 1, cue up 2. Seamless
handover at end of 1. etc etc....

Take even deeper bow.

d

--
Pearce Consulting
http://www.pearce.uk.com

[Keith G]

"dizzy" wrote in crossposted message
...
Marc Wielage wrote:

For some odd reason, there are people who foolishly convert MP3 files
to FLAC
(or APE), perhaps in the mistaken belief that it will make the signal
"sound"
better.

Sounds like those who buy "tubed" CD players, thinking that the one
tube stage at the player's output will somehow "fix" all the "harm"
done to the signal by all the solid-state stuff.



Why? Doesn't it?

[Keith G]

"Don Pearce" wrote in message
...
On Tue, 26 Jun 2007 11:43:01 +0100, "Keith G"
wrote:


Not as confusing as numbering 2-disc sets of LPs 1/4 and 2/3 for
public
performance - where the playing order goes/went as follows:

Stack the albums with sides in this order from the top: 1/4, 3/2

Play Side 1, flip both discs together

Play Side 2, flip top disc only

Play Side 3, remove top disc

Play Side 4, remove disc, take bow, bring up house lights....




Or for preference, have two decks, then: Play 1, cue up 2. Seamless
handover at end of 1. etc etc....

Take even deeper bow.



Doesn't quite work - with a 1/4 & 2/3 numbered set he'd have plenty of
time to flip the Sides 1/4 disc on one deck, but would have to flip the
Sides 2/3 disc *real time* on the other anyway and both discs 'real
time' in the case of 1/2 & 3/4 numbered sets!

(Those ole boys weren't so daft, back then - not to mention who TF had
the money for *two decks* in those days, also?! ;-)

Reminds me: There was a feature on BBC Look East some months back about
a DJ who uses 2 wind-up gramophones playing 78s - he is able to change
the record, wind the deck up and *change the needle* while the other
record is playing, apparently!

[Don Pearce]

On Tue, 26 Jun 2007 12:24:09 +0100, "Keith G"
wrote:


"Don Pearce" wrote in message
...
On Tue, 26 Jun 2007 11:43:01 +0100, "Keith G"
wrote:


Not as confusing as numbering 2-disc sets of LPs 1/4 and 2/3 for
public
performance - where the playing order goes/went as follows:

Stack the albums with sides in this order from the top: 1/4, 3/2

Play Side 1, flip both discs together

Play Side 2, flip top disc only

Play Side 3, remove top disc

Play Side 4, remove disc, take bow, bring up house lights....




Or for preference, have two decks, then: Play 1, cue up 2. Seamless
handover at end of 1. etc etc....

Take even deeper bow.



Doesn't quite work - with a 1/4 & 2/3 numbered set he'd have plenty of
time to flip the Sides 1/4 disc on one deck, but would have to flip the
Sides 2/3 disc *real time* on the other anyway and both discs 'real
time' in the case of 1/2 & 3/4 numbered sets!

(Those ole boys weren't so daft, back then - not to mention who TF had
the money for *two decks* in those days, also?! ;-)

Reminds me: There was a feature on BBC Look East some months back about
a DJ who uses 2 wind-up gramophones playing 78s - he is able to change
the record, wind the deck up and *change the needle* while the other
record is playing, apparently!



I was thinking about that - are you sure they weren't 1/3 and 2/4?

d
--
Pearce Consulting
http://www.pearce.uk.com

[Keith G]

"Don Pearce" wrote in message
...
On Tue, 26 Jun 2007 12:24:09 +0100, "Keith G"
wrote:


Doesn't quite work - with a 1/4 & 2/3 numbered set he'd have plenty of
time to flip the Sides 1/4 disc on one deck, but would have to flip
the
Sides 2/3 disc *real time* on the other anyway and both discs 'real
time' in the case of 1/2 & 3/4 numbered sets!

(Those ole boys weren't so daft, back then - not to mention who TF had
the money for *two decks* in those days, also?! ;-)

Reminds me: There was a feature on BBC Look East some months back
about
a DJ who uses 2 wind-up gramophones playing 78s - he is able to change
the record, wind the deck up and *change the needle* while the other
record is playing, apparently!



I was thinking about that - are you sure they weren't 1/3 and 2/4?


No, I've never seen that numbering - I've got one or two sets numbered
1/4 & 2/3 and plenty numbered 1/2 & 3/4.

I got into a palaver taking photos to show the numbering - I realised
this pic:

http://www.apah69.dsl.pipex.com/show/MaVlast.JPG

*proved* nothing, so I had to take this pic:

http://www.apah69.dsl.pipex.com/show/MaVlast2.JPG

to leave you to deduce where Side 3 was, but of course the camera
battery ran out after the first pic so I had to use a second camera!!

(It's a bugger trying to get two record labels into the one shot! :-)