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[Frobozz]

It would be very nice if MC had some way of correcting CDs that have pre-emphasis either during ripping or afterward.  I just spent way too much time last night and into the early morning trying to figure out how to properly rip an old copy of "The Wall" that has pre-emphasis.  Before last night I didn't even know what pre-emphasis was.  Now I know more about it than I ever wanted to know.

It shouldn't take hours of research to figure out how to properly rip a CD that happens to have pre-emphasis.  The ripper should just do the right thing and make a file that will sound right.

I tried MC and the rip did not sound right.  Then I tried EAC and had the same result.  Then I hit Google to figure out what the heck was wrong.  Hours later I had a couple potential solutions. 

iTunes will automagically correct pre-emphasis when ripping.  It seems to be the only (or one of the very few) rippers that does.

I also found a free tool called SoX Sound eXchange that can correct for CD pre-emphasis.  I tried that tool as well.

I listened to the results of the iTunes rip and the rip corrected using SoX.  To my ears the SoX corrected rip sounded better.  So that's the rip I went with.

Way too much time and effort for all of that.  It shouldn't be so difficult.  Please make it easier.

[benn600]

You should include a summary of what pre-emphasis is since it is the basis of your post and you didn't know what it was.

[Alex B]

I think Sox is the best option available today.

I have a few old 80's CDs with pre-emphasis, but it is not commonly used anymore.
Here is what I would do if I still had unripped pre-emphasized CDs:

- Rip to single wav file & cue sheet.
- Process the wav with Sox.
- Mount the "wav + cue" disc image with Daemon Tools, Virtual Clone Drive or some other virtual CD drive emulator.
- Rip the virtual disc to track files with MC.

Some old links:
http://yabb.jriver.com/interact/index.php?topic=26276.0
http://yabb.jriver.com/interact/index.php?topic=45366.0
http://yabb.jriver.com/interact/index.php?topic=40270.msg274867#msg274867

[Frobozz]

You should include a summary of what pre-emphasis is since it is the basis of your post and you didn't know what it was.

Yes, I should have.  Problem is, I still don't understand how pre-emphasis works and why it's added.  My understanding is that it has to do with noise suppression or noise masking.

What it does is add an EQ curve to the recorded audio.  It is like ramping up the trebble and high frequencies on an EQ.  That is the pre-emphasis part.  Then on playback you undo that with a de-emphasis that gets you back to a flat curve.

If you listen to a CD that has pre-emphasis and don't apply de-emphasis you end up with something that sounds like someone took the treble knob and turned it up to max.

It is the responsibility of the DAC or CD player to apply de-emphasis when the CD has a flag set indicating it has pre-emphasis.  The problem is when you rip a CD you bypass the DAC and end up with the raw audio before the de-emphasis has been applied.  There is also a problem that not all CD players and DACs now bother to do de-emphasis or the manner of playback manages to bypass the pre-emphasis flag.  So nowadays you are not guaranteed being able to properly play a pre-emphasis CD on all CD players or computer setups.

Now that I know what de-emphasis is and what it sounds like when a CD doesn't get properly de-emphasised, I'm going to have to go through my collection and see if some of my CDs are not ripped correctly.  Grrrr...

[Frobozz]

I have a few old 80's CDs with pre-emphasis, but it is not commonly used anymore.
Here is what I would do if I still had unripped pre-emphasized CDs:

- Rip to single wav file & cue sheet.
- Process the wav with Sox.
- Mount the "wav + cue" disc image with Daemon Tools, Virtual Clone Drive or some other virtual CD drive emulator.
- Rip the virtual disc to track files with MC.

That's about what I ended up with.  My workflow ended up being:
- Rip to a single WAV and CUE sheet using Exact Audio Copy
- Process the WAV with Sox
- Edit the CUE to point to the processed WAV file
- Load the CUE in Foobar2000
- Use Foobar to convert the tracks to FLAC and MP3

That seemed to be the most straightforward way that would keep the basic tagging info (album, artist, title, track).  The tagging info is in the CUE sheet.  Foobar reads it from the CUE and tags the converted files.

Media Center can also read and play CUE sheets so I could have used MC to do the file conversion.  I just wasn't thinking of that in my sleep deprived state.

Not the easiest way to rip, but could be worse.  I saw a few comments by the developer of dbPoweramp that the next version of the dbPoweramp ripper may include de-emphasis for pre-emphasis CDs.

My Columbia C2K 36183 release of "The Wall" is sounding good.   

[benn600]

So it was pre-setup for radio broadcast, right?  Are there any modern CDs that have it?  I'm curious if I have any.  The way you make it sounds, it must be pretty obvious that it had the filter applied.

[Frobozz]

The CD is for regular home playback. Not a special situation for radio broadcast.  Radio broadcasting does you pre-emphasis and de-emphasis as well to reduce noise.  But in this case the CD pre-emphasis is not because of radio.

It is claimed to be rare for modern CDs.  More likely to be on CDs from the early 80s.  But it's also claimed that classical CDs continued to use it and may still use it.  There are old classical CD masters that continue to get resold to budget CD labels.  Some of those could be CD masters with pre-emphasis, so I can see it popping up on modern budget classical CDs.

I don't know how common it was and how long it was in use.  I'm going to have to go through my collection and see how many I have.  I only recently (in the past year) got my entire CD collection ripped.  Now I have to go back and recheck a bunch of them to check for pre-emphasis.  You can check for pre-emphasis by scanning the CD with EAC (Exact Audio Copy) and looking at the far right-hand column.  You can also check for pre-emphasis using dbPoweramp CD Ripper, adding the "Track Technical" column and checking if it mentions pre-emphasis.

Once you know what pre-emphasis does you'll know the sound when you hear it.  It is not subtle, but if you don't know you could miss it or pass it off as that's how that CD sounds.  Alex posted a link to a picture of an EQ curve that applies de-emph.  Reverse that curve and you get what pre-emphasis looks like.

It was obvious something was wrong on my Pink Floyd CD because the cymbals were way hot and vocals and guitars didn't sound like I knew the album sounded.  On a pure classical CD it might be a little more difficult to pick out.

[benn600]

Very interesting info, thank you.

Would you want to post a less than 30 second clip as an example?  Did you determine the actual purpose for it?  Why would they emphasize the treble and then have a flag to enable de-emphasizing?  I could see some reason for emphasizing the treble which is more fragile and more likely to be lost or ignored by less spectacular encoders or tweeters.

This is my 3000th post!  Although I think it is actually 3,100 because J River strangely adjusted my number last time I posted about the significance.  Viewing my post listing accounts for 3,100 (62 pages * 50 posts).

[Frobozz]

Would you want to post a less than 30 second clip as an example? 

I can post a 30 second clip.  Any suggestions for an upload location? 

[JimH]

In MC, select the file, and then use "Share to Web" to upload to our Pix01 site.

[Frobozz]

I created a Pix01 album.  The audio files are there but you can't download or play them.
The album is at http://pix01.com/EZ@Ihu2 so you can see what it's doing.

I'll have to hunt around for a suitable upload site.  When I find one I'll post back here.

I did a sampling of my classical CD collection and already found five CDs that have pre-emphasis.  I'm using dbPoweramp CD Ripper to identify the discs with pre-emphasis.

The five found so far are 3 on the BIS label, 1 on Delos, and 1 on Deutsche Grammophon.  I have more Delos and BIS CDs from that era so I expect to find more.

Only one of the five got any play time since I ripped it.  I remember it sounding strange.  Identifying classical CDs that have pre-emphasis just by listening is more difficult than rock CDs.  Unless the classical works have high violins, high flutes, or cymbals it is not going to jump out at you.  What I've found is if you listen to an entire work and somewhere along the way to get the feeling that things are harsh and too treblely, you've probably got a CD with pre-emphasis.

[benn600]

You can upload directly on this forum I think.  I've seen others attach files.  I cannot find the method while I look at the new-post page right now, though.  I look forward to hearing the files when you can figure it out.

[Frobozz]

I didn't forget about this thread.  I just got distracted for a bit.

Let's try divShare for an upload location.  They claim files won't get deleted.  It has ads and the download page is a bit busy.  It has a streaming MP3 player on the page and there is a download link on the right that will download the currently playing file.

divShare link: http://www.divshare.com/download/6869823-01f

The preemph file is the file as it is ripped from the CD, which includes the pre-emphasis boost
The deemph file is after running the file through SoX to apply de-emphasis

I also found a good explanation of the what and why of pre-emphasis along with some technical info and a table of EQ levels for different frequencies.  It's at the addenda page for audioXpress Online.  Scroll down to "A De-Emphasis Test CD by Gary Galo" and download Galo3025.pdf.  Direct linking to the PDF doesn't work.

[benn600]

I prefer the pre-emphasis version.  I like extra bright detail -- to some extent.  It sounds like treble is being removed and, therefore, sonic detail lost in the de-emphasis version.  Interesting to hear other responses!

[Frobozz]

The pre-emphasis version does have an exciting detailed sound to it.  But it's also a sound that gets tiresome or overdone if you listen to an entire album like that, especially if you have headphones or speakers that are revealing of treble detail.  For 30 seconds though it sounds very interesting.

The guitar in the pre-emphasis version has more of an edge but the sound of the organ (at the end of the clip) is wrong. 

[Jim HTPC]

Get the re-mastered version of The Wall.  No pre-emphasis is used according to EAC when it analyzed my discs.

[Frobozz]

I have the remastered version of The Wall as well, along with the Mobile Fidelity Sound Labs gold CD mastering.  It's fun to have the different versions.  Each is mastered differently.

The original release (Columbia C2K) sounds better than the remastered version for critical listening.  The remastered version got boosted in loudness and lost some dynamics in the process, but does have a more rock sound as a result.  The MFSL version is my favorite for headphone listening with the Columbia C2K version coming in a close second.

[benn600]

I was comparing it to some "hot" new CDs and find that the treble detail is present in a lot of the newer CDs.  My speakers have beryllium tweeters which are definitely brighter and more revealing.  I agree it can be overwhelming but as I was saying, some new CDs have easily that much treble detail.  I wonder if it has anything to do with trying to overpower earbuds so that extra detail is present -- except treble should be the easier part for earbuds.

There is no RIGHT answer I guess.

[hit_ny]

I also prefer the pre-emphasis clip, the other sounds quite flat in comparison.

..and you say its easier to tell with rock than classical  ?

In that case i think i wont mind a bit or pre-emp with my classical at all 

As to whether its tiring to listen to for an extended period of time, i beleive loudness or overuse of compression is the bigger offender.

[Frobozz]

"The Wall" isn't the best demo sample for pre-emphasis.  The Pink Floyd sound is rather muted.  They don't have a bright sound at all.  Adding some brightness can make it more exciting and bring out details in the sound that are otherwise obscured.  Unfortunately I haven't found any other rock CDs in my collection that have pre-emphasis yet.

What is the right sound anyways?  It's subjective especially for rock music.  The mastering engineer gets to make lots of decisions on what the sound will be.  The fact that all three masters of "The Wall" that I have each have a different sound is an example of that.  The remaster version does have the cymbals more prominent and tingly.  It sounds more modern, but I don't think it is a sound that fits Pink Floyd.

When I get around to re-ripping my affected classical CDs I'll post a clip here of both pre-emphasis and de-emphasis.  If you know how violins are supposed to sound like in a symphony orchestra you can identify the pre-emphasis.  But it's like the Pink Floyd, a symphony has a muted kind of sound where added brightness can bring out details and harmonics that can sound more interesting, but ultimately are not the "right" sound.

[benn600]

People should choose bright speakers if they like that sound.  Different brands (and models) are known for being brighter or darker.  Of course there are a lot of other descriptors for sound.