More audio tomfoolery

**John R Leddy** · #1 (**permalink**) July 15th 15, 10:15 PM

Quote:

Originally Posted by Eiron[_3_]

On 15/07/2015 16:32, Jim Lesurf wrote:

shows ADC/processing flaws. And a while ago they produced CDs with the
pre-emphasis flag bit 'on' when the audio isn't pre-emphasised. Slip
somewhere when someone 'improved' something.

If you copy it to .wav files, then write them to another CD,
you will probably fix that. Do you have any examples?
Something I might have in my collection?

On the other hand, if you 'rip' a CD with pre-emphasis,
it will probably have 10dB of HF boost.

--
Eiron.

I duly installed the Nyquist de-emphasis plug-in for Audacity, but so far EAC hasn't identified a CD as having pre-emphasis.

**Jim Lesurf[_2_]** · July 16th 15, 08:54 AM posted to uk.rec.audio

In article , John R Leddy
wrote:
duly installed the Nyquist de-emphasis plug-in for Audacity, but so far
EAC hasn't identified a CD as having pre-emphasis.

In my experience it is quite rare. Also in my experience many CD players
don't even bother to check for the flag and impliment it.

The orginal Audio CD specs did include an option for 'four channel' halving
the available duration. But so far as I know, no-one ever made such a disc
or a player for them. Audio CD pre-emphasis seems to have gone the same
way. And the flag may appear on occasion purely as an accident during
generation of the CD image for manufacture.

Jim

--
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