HydrogenAudio

Hydrogenaudio Forum => General Audio => Topic started by: Boiled Beans on 2009-01-25 10:11:15

Title: Definite way for checking for pre-emphasis
Post by: Boiled Beans on 2009-01-25 10:11:15
Is there a definite method for checking pre-emphasis on CDs? Many of the CDs with pre-emphasis don't even light up the EAC flag.

Is the track peak a reliable gauge to pre-emphasis? Those with pre-emphasis have a large drop in track peak after running through Sox.
Brothers in Arms drops from 1.00 to 0.77
Toto IV drops from 0.86 to 0.66

Tried a modern CD
Oasis' Dig Out Your Soul drops from 1.00 to 0.98

I've tried other files which I thought had pre-emphasis but the track peak doesn't drop much.
Never Mind the Bollocks drops from 0.87 to 0.83
U2's Boy and War drops from 1.00 to 0.98
These sounded a bit murky as well after the de-emphasis
Can I safely conclude these have no pre-emphasis?
Title: Definite way for checking for pre-emphasis
Post by: Surfi on 2009-01-25 14:58:09
::

If you're familiar with the command line use cdda2wav for this. It's part of the cdrtools package. You can get Win32-Binaries here:

Free Software (http://www.student.tugraz.at/thomas.plank/)

Unzip cdda2wav.exe to EAC's CDRDAO-Folder (it's in need of cygwin1.dll).


Best regards ...

::
Title: Definite way for checking for pre-emphasis
Post by: Boiled Beans on 2009-01-27 04:27:35
I haven't downloaded the software yet, but from I've read on the website, isn't that just a CD burning software? What has it got to do with identifying pre-emphasis?
Title: Definite way for checking for pre-emphasis
Post by: Surfi on 2009-01-27 09:23:47
::

You should download the package and you can use cdda2wav to identify pre-emphasis, I do that too. The advantage of cdda2wav: It does analyze both (TOC and subchannel) and is telling you if there's differences (that should'nt be there). Toto IV has pre-emphasis flagged in the subchannel but not in the TOC. This is the reason why EAC doesn't show it (at least I think so).

... sorry for my bad english ...


Greetings ...

::
Title: Definite way for checking for pre-emphasis
Post by: Gregory S. Chudov on 2009-01-27 11:49:22
I don't think there can be a reliable way to detect preemphasis from the audio itself.
You can reliably detect preemphasis on the original CD by scanning subchannel information, as all hardware CD players do.
Unfortunately, EAC doesn't do this, and relies on the CD TOC, which often doesn't contain such information.
So you'll have to wait untill EAC team fixes this, or until i finish CUERipper
Title: Definite way for checking for pre-emphasis
Post by: Surfi on 2009-01-27 16:14:35
You can reliably detect preemphasis on the original CD by scanning subchannel information, as all hardware CD players do.

::

... but this is exactly what cdda2wav.exe does, you need to have the original CD in your drive ...

::