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JayKay65
July 18th 03, 05:07 PM
Hi,

Possibly a stupid question, but I'm an amateur, so forgive me.

I've noticed when extracting audio from a CD, older discs seem to
retain the peaks and valleys of their dynamic range, while newer discs
seem to be severely clipped.

I'm guessing the problem is "bit depth", in that newer CDs are
commonly mastered in 24-bit, and I'm extracting using a 16-bit sound
card.

Can anyone tell me if upgrading to a 24-bit card will correct this?

Thanks....
JK
CJT
July 18th 03, 06:59 PM
JayKay65 wrote:
> Hi,
>
> Possibly a stupid question, but I'm an amateur, so forgive me.
>
> I've noticed when extracting audio from a CD, older discs seem to
> retain the peaks and valleys of their dynamic range, while newer discs
> seem to be severely clipped.
>
> I'm guessing the problem is "bit depth", in that newer CDs are
> commonly mastered in 24-bit, and I'm extracting using a 16-bit sound
> card.
>
> Can anyone tell me if upgrading to a 24-bit card will correct this?
>
> Thanks....
> JK

Use something like EAC and it won't be an issue.

www.exactaudiocopy.de
TCS
July 18th 03, 07:58 PM
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begin On 18 Jul 2003 09:07:29 -0700, JayKay65 > wrote:
> Hi,
>
> Possibly a stupid question, but I'm an amateur, so forgive me.
>
> I've noticed when extracting audio from a CD, older discs seem to
> retain the peaks and valleys of their dynamic range, while newer discs
> seem to be severely clipped.
>
> I'm guessing the problem is "bit depth", in that newer CDs are
> commonly mastered in 24-bit, and I'm extracting using a 16-bit sound
> card.

No CDs are mastered at 24 bits. CD is a 16 bit medium. They may be
recorded and mixed at 24 bits, but all CDs are mastered at 16 bits.

For extracting the data, the bitness of your soundcard is usually
irrelevent as the data is read off the sound card without every being
converted to analog and back. Check that whatever program you're using
to rip the CD data is doing a digital extraction.

As far as newer discs seeming to be severely clipped, it is probably
due to excessive compression where quieter passages are boosted and louder
passages are attenuated. This is more a sign of music catering to
mediocre sound systems or radio.
TCS
July 18th 03, 08:23 PM
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begin On 18 Jul 2003 18:58:02 GMT, TCS > wrote:
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> begin On 18 Jul 2003 09:07:29 -0700, JayKay65 > wrote:
>> Hi,
>>
>> Possibly a stupid question, but I'm an amateur, so forgive me.
>>
>> I've noticed when extracting audio from a CD, older discs seem to
>> retain the peaks and valleys of their dynamic range, while newer discs
>> seem to be severely clipped.
>>
>> I'm guessing the problem is "bit depth", in that newer CDs are
>> commonly mastered in 24-bit, and I'm extracting using a 16-bit sound
>> card.
>
> No CDs are mastered at 24 bits. CD is a 16 bit medium. They may be
> recorded and mixed at 24 bits, but all CDs are mastered at 16 bits.
>
> For extracting the data, the bitness of your soundcard is usually
> irrelevent as the data is read off the sound card without every being
ooops: data is read off the CD without the soundcard ...

> converted to analog and back. Check that whatever program you're using
> to rip the CD data is doing a digital extraction.
>
> As far as newer discs seeming to be severely clipped, it is probably
> due to excessive compression where quieter passages are boosted and louder
> passages are attenuated. This is more a sign of music catering to
> mediocre sound systems or radio.
JayKay65
July 18th 03, 11:52 PM
Ahhh yes, that makes sense. Muchas gracias for the info!

<Homer Simpson voice>
Stupid music industry
</Homer Simpson voice>

So... any advice on where to find commonly used industry compression
ratios, so I can at least pump the loudness of the older tracks up to
match the newer ones?

(in case that suggested app doesn't work)?

TCS > wrote in message sol.net>...

> As far as newer discs seeming to be severely clipped, it is probably
> due to excessive compression where quieter passages are boosted and louder
> passages are attenuated. This is more a sign of music catering to
> mediocre sound systems or radio.
Arny Krueger
July 19th 03, 10:46 AM
"JayKay65" > wrote in message
om

> Possibly a stupid question, but I'm an amateur, so forgive me.

There are no stupid questions if asked with honest intent. Your intent is
obviously honest.

> I've noticed when extracting audio from a CD, older discs seem to
> retain the peaks and valleys of their dynamic range, while newer discs
> seem to be severely clipped.

That's because that is how those CDs were intended to be made. The clipping,
etc is called "Supercompression" among other things. It is done
intentionally to make the music appear to be loud and have a in-your-face
type sound.

What you are seeing are the result of artistic decisions made by the
producers of the recordings. Technological limits or bit depth have nothing
at all to do with it.

> I'm guessing the problem is "bit depth", in that newer CDs are
> commonly mastered in 24-bit, and I'm extracting using a 16-bit sound
> card.

Nope, its because that's what the producers of the recordings wanted to
deliver to their listeners.

> Can anyone tell me if upgrading to a 24-bit card will correct this?

Nope.
Arny Krueger
July 22nd 03, 02:21 AM
"JayKay65" > wrote in message
m
> I appreciate all your help, but there's still one thing that confuses
> me:
>
> If the audio is "supercompressed" in the production phase before being
> written to the CD, then why isn't it clipped when I extract it using
> an analog method instead of digital? The quality of an analog
> extraction is pretty low-fi, but there are intact peaks.

The low quality of the analog extraction might be concealing the clipping.

> Is it that the frequency response of an analog extraction isn't as
> good as that of digital, and the missing data is creating the illusion
> of peaks?

That's probably it.