CD Pre-emphasis: How to detect? What software to rip? Tagging?

[miguelito]

Hi all,

 

@Archimagopost about pre/de-emphasis (https://archimago.blogspot.com/2020/09/how-to-cd-pre-emphasis-and-dealing-with.html) got me thinking about this...

 

I found a Roon-based filter that will do the de-emphasis: https://community.roonlabs.com/t/de-emphasis-curve-was-parametric-eq-functions/123336/11?u=miguelito

 

However, a few questions remain:

 

1- XLD seems to support detection of pre-emphasis in both the subcode and TOC (https://wiki.hydrogenaud.io/index.php?title=Comparison_of_CD_rippers). But how is this then used? Does it write a tag to the ripped file to indicate this? 

 

2- Apparently not all CD drives support extraction that would allow you to detect pre-emphasis in the subcode. How do I find out if my CD drives support this?

 

Thx!

[miguelito]

Pretty sure I do. Some of the 80s releases are thin sounding and I always assumed they were “mastered for walkman” so that there was not that much bass, but I am starting to think that it’s probably pre-emphasis also.

[miguelito]

Funny enough, I've encoded about 1500 CDs and I cannot find one with pre-emphasis!

[miguelito]

A brief recap on how I am going to deal with pre-emphasis:

 

The fool-proof way to determine if a CD has pre-emphasis is at rip time (via the cue sheet - I don't think there are other ways). If this indicates pre-emphasis then run the rip through the appropriate de-emphasis fiter (sox everywhere or xACT on the mac). However, I have thousands of ripped CDs (and have them all in storage) and I am not going to bother to re-rip just to be sure.

 

The next most accurate method for CDs you've already ripped is to capture the first track from a streaming service (Qobuz or TIDAL), calc the frequency spectrum (eg with MusicScope on the mac) and compare that to your rip's spectrum. Normalize by considering the difference around 200Hz, and if the 16KHz region of the spectrum is roughly 9dB down in the capture vs your rip, then your rip has pre-emphasis. This assumes of course that streaming services dealt with pre-emphasis to begin with, which I think is NOT the case across the board (see side note below).

 

Finally the simplest method - and the least accurate one - is to play your rip and compare the sound to the streamed version. If your  rip sounds bright and harsh in comparison, then you probably want to try a de-emphasized version. This again assumes that the streaming service file is properly de-emphasized in the digital master in the first place.

 

If you use Roon, you can also create a simple high shelf filter based on the post linked below and toggle that filter on and off and determine which sounds more correct.

 

As a side note, there's one CD that I always thought was bright and harsh - Vivaldi's Stabat Matter feat Andreas Scholl (Harmonia Mundi). The streaming version sounds the same as my rip, but if in Roon I engage the de-emphasis filter, it sounds a lot more natural to my ears.

 

De-Emphasis in Roon:

https://community.roonlabs.com/t/de-emphasis-curve-was-parametric-eq-functions/123336/22?u=miguelito

[miguelito]

You can use sox on Windows.

 

Take a look at:

 

https://archimago.blogspot.com/2020/09/how-to-cd-pre-emphasis-and-dealing-with.html