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

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

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."

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.

"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

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."

"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

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

"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

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