Help! Pre-Emphasis Questions

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
I read online about how pre-emphasis is sort of rare, and one collector said he only had one CD in his collection that had pre-emphasis! I have three. 😱 A cursory search in my CD rip folder gave me three CUE sheets with "FLAGS PRE." (I haven't finished ripping my entire CD collection…)

Here are the deets about my pre-emphasis CDs:
  • Boz Scaggs – Hits! – Japanese release, CBS/Sony 25DP 5018. Released June 22, 1988.
  • Pink Floyd – Dark Side of the Moon – Harvest CDP 7 46001 2. Per Discogs, released in August 1984.
  • Billy Joel – Piano Man – Columbia CK 32544. Pitman pressing, according to Discogs. Unknown year.
I had suspected that DSOTM had pre-emphasis, but had no idea the other two did as well. I use XLD to rip my CDs. I like that XLD spits out beautiful log files and cue sheets on command. What software do you recommend I use to "de-pre-emphasis" my wav files? Is there such a thing?
 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
Oh, well I did some more research and came across a nifty cross-platform program called SoX.

If any of you have any WAV+CUE rips of CDs that have pre-emphasis and want to de-emphasis them but don't know how, let me know. The CDs don't sound so bright anymore now that pre-emphasis has been removed by SoX.
 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
@Chris May or @Harry any other Carpenters/A&M guru... I'm 99% sure that the Carpenters' discography did not have pre-emphasis at any point. However, re-listening to some of the AM+ CDs from the '80s--for example, "I Won't Last a Day Without You" on "A Song for You," or "B'wana She No Home" on "Passage," or all of "Made in America"--they're so bright, I think the sound could have been helped by de-emphasis. Does anyone know if there's a story here? I applied de-emphasis on "B'wana," (AM+) and the resulting spectrogram looked maybe halfway between the AM+ CD (very bright!!) and the Remastered Classics CD (very muddy!!).

This also reminds me that "Christmas Collection" on Qobuz and iTunes are very very very bright. I love the sound on the AM+ "Special Edition" CD but wish I could hear the tracks as they were originally presented in 1978 and 1984, respectively...

Just curious to know if the original master tape was really that bright, or if pre-emphasis was applied without being flagged as such on the CD.
 

Harry

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I'm not aware of any pre-emphasis on Carpenters CDs. Brightness is something that we older types appreciate. As you get older, your hearing will lose the ability to hear those higher frequencies, so brighter CDs tend to sound better to us.

Your younger ears are hearing most of those highs, and some in your age group don't like bright sounding recordings.

My own hearing has lost a good bit above 10khz. An example: There's a favored Herb Alpert Tijuana Brass track on the WARM album called "The Sea Is My Soil" (O Mar é Meu Chão). At around the 40-45 second mark, the record has a "tick, tick, tick" percussion coming from the left channel. I used to use that as a system checker to make sure speakers were hooked up correctly. Unfortunately for me, that ticking sound is just above what I can hear these days. It's all but gone for me. :sad:

I've even used Audacity to verify that the sound is still there - I just can't hear it.
 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
I'm not aware of any pre-emphasis on Carpenters CDs. Brightness is something that we older types appreciate. As you get older, your hearing will lose the ability to hear those higher frequencies, so brighter CDs tend to sound better to us.

Your younger ears are hearing most of those highs, and some in your age group don't like bright sounding recordings.

My own hearing has lost a good bit above 10khz. An example: There's a favored Herb Alpert Tijuana Brass track on the WARM album called "The Sea Is My Soil" (O Mar é Meu Chão). At around the 40-45 second mark, the record has a "tick, tick, tick" percussion coming from the left channel. I used to use that as a system checker to make sure speakers were hooked up correctly. Unfortunately for me, that ticking sound is just above what I can hear these days. It's all but gone for me. :sad:

I've even used Audacity to verify that the sound is still there - I just can't hear it.
I'm sorry to hear that regarding "The Sea Is My Soil." Whoa... I just adjusted the volume down (since I'm at work) and I can't hear the tick-ticking at this volume level. (I thought the ticking stopped altogether...) A little touch up and I hear it clear as a bell.

I do generally like the bright sound of the AM+ CDs. Some of the mixes (like "B'wana") are on the verge of being excessive to my ears, but they're nowhere near as excessive as the digital download of "Christmas Collection."

The pre-emphasis discs I have didn't grate my ears like many people said online, but after applying SoX de-emphasis, I can hear now how the sound has shifted in a way that relieves my ears with regard to the higher-end frequencies (like the clock/alarm bell sounds in "Time" by Pink Floyd).
 

Harry

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Also unfortunately, that master tape of Sea Is My Soil is damaged on all digital releases. I always go back to the original WARM vinyl for that track.
 

GDB2LV

Well-Known Member
And B’Wana is just not mixed well, period. I can’t believe Richard let that slip out that way. The stereo is so poor, even the surround sound can’t decode it. Barely anything but echo once in awhile on the rear speakers. It’s a great cut otherwise. The rest of the album, cd or vinyl is mixed just fine.
 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
The stereo is so poor, even the surround sound can’t decode it. Barely anything but echo once in awhile on the rear speakers. It’s a great cut otherwise.
I wonder if the mostly-mono mix was intentional, maybe to recreate a Phil Spector-type "Wall of Sound." The mono/stereo aspect to me reminds me of Queen's "Mustapha" from 1978. The song begins very mono, and then blows up into full stereo for certain bridges, then goes back to mono, then back to stereo. The big difference is, of course, "B'wana" is basically mono to my ears with the exception of a few moments beginning at around the 3:00 mark.

Imagine how nice it would be to hear the güiro beginning at 1:02 shifted to the left channel (either partially or completely), for instance...
 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
Pink Floyd "The Dark Side Of The Moon" (Harvest & Mobile Fidelity Sound Labs) both ran 42:58 in length!!!
By jove, you're right! iTunes is telling me my album is 43 minutes long. My WAV file is 42:56. (I have the Harvest CD.) I never realized that this album was so long haha!

According to my XLD log, album gain is 1.78 db and the peak is 0.723877. De-emphasis makes it even quieter and less sharp in the high frequencies.
 
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Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
First is the pre-emphasis waveform of DSOTM:
Screenshot-2021-06-25-142348.png


Now, after SoX "deemph" has been applied:
Screenshot-2021-06-25-142404.png


In particular, you'll notice around 8 minutes the bells/alarms/chimes cease to be the loudest segment of the waveform. :)
 

Rudy

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I think I had a filter in Sound Forge that similarly removed the pre-emphasis--that was just an EQ applied during mastering (pre-emphasis) and removed during playback (de-emphasis). Typically that sort of thing was done to reduce noise, so it never made sense in the CD era, with digital having a mostly silent background to begin with.

I think only had a couple of those CDs from the early days, all imports. The same Boz Scaggs Hits (which was a different track selection from the US LP version), and I think the Toto Hydra CD from Japan was as well (it was on the same label), although the latter I replaced with the SACD that is worlds better, as is the set of remasters in recent years that were also released as hi-res. Much smoother, far more detail than that ancient CD.

Short version? Not many CDs had pre-emphasis--it was rarely used.
 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
Not many CDs had pre-emphasis--it was rarely used.
That's really good to know. I'm kind of surprised that I had three. I was expecting maybe one, two at the most... After applying de-emphasis, I must admit, Boz Scaggs Hits sounds much better than before (you're right—the track listing is different from the U.S. LP).
 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
Sorry -- I am flooding the forums, I apologize... just have many thoughts and want to put them out there in writing somewhere...

When I put in my pressed Alfa Voice of the Heart disc in iTunes and EAC, the pre-emphasis isn't recognized. Only XLD recognizes the pre-emphasis and writes it in the CUE sheet as "FLAGS PRE."

Just now, I made an exact CD-R burn from the WAV + CUE sheet using XLD (verified w/AccurateRip), and now iTunes is recognizing the pre-emphasis. I verified with the waveform that iTunes is ripping the CD with de-emphasis. Not sure why the pressed CD doesn't trigger pre-emphasis but my burned CD does. I'm currently testing with other pre-emphasis discs I own, like Dark Side of the Moon (Harvest pressing).
 

Rudy

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For me it's a non-issue, as the three or four CDs I had with pre-emphasis are now sold and replaced with better versions. 😉 They never sounded all that good, even played back through CD players that could apply the de-emphasis. (Levels were too low, and the mastering was still too bright, typical of Japan CDs IMHO.)
 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
For me it's a non-issue, as the three or four CDs I had with pre-emphasis are now sold and replaced with better versions. 😉 They never sounded all that good, even played back through CD players that could apply the de-emphasis. (Levels were too low, and the mastering was still too bright, typical of Japan CDs IMHO.)
Eureka! Surprisingly, iTunes does a good job at knocking down that some of that brightness during the rip process. I'm listening to "Thriller" now, which had pre-emphasis and was way too bright. I made an exact CD copy (AccurateRip verified) and imported it into iTunes as Apple Lossless... it sounds much better to my ears now. Dynamic and just bright enough to keep the ear entertained without being grating.
 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
Dare I say... the iTunes de-emphasis algorithm sounds better than SoX. 👀
 

Rudy

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Eureka! Surprisingly, iTunes does a good job at knocking down that some of that brightness during the rip process. I'm listening to "Thriller" now, which had pre-emphasis and was way too bright. I made an exact CD copy (AccurateRip verified) and imported it into iTunes as Apple Lossless... it sounds much better to my ears now. Dynamic and just bright enough to keep the ear entertained without being grating.
Was that an import version of Thriller? I don't recall pre-emphasis being used on any US titles, and I had a stock Columbia copy of that one. (I have the SACD, so no need to keep the CD.) Far as I remember, the very few titles I ever found with pre-emphasis were from Japan, and mastered too brightly even with de-emphasis properly applied. (Never cared for Japan's mastering on anything, for that matter. Always too bright.)
 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
Was that an import version of Thriller? I don't recall pre-emphasis being used on any US titles, and I had a stock Columbia copy of that one. (I have the SACD, so no need to keep the CD.) Far as I remember, the very few titles I ever found with pre-emphasis were from Japan, and mastered too brightly even with de-emphasis properly applied. (Never cared for Japan's mastering on anything, for that matter. Always too bright.)
Catalog no. 35.8P-11. This one isn't too bright imho. I ripped it using iTunes. I read somewhere online that the iTunes algorithm knocks off more of the high-end than others like SoX, so imho the bass is very present and it allows for turning the volume out without being overpowering. Thriller is kind of a treble-y album to begin with tho. "The Girl Is Mine" has a very pleasing sound; not too bright at all.


(The audio above is after iTunes de-emphasis was applied.)

The waveform actually shows nice peaks and valleys too. The other songs are a little bright, but in the way that a relatively flat transfer would sound, without artificial bass boosting or peak limiting. But I have to say, the drums on this album are very punchy, so if you like a good beat, it sounds pretty good.
 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
Another McCartney/Jackson collaboration from a pre-emphasis disc. Audio is post-iTunes de-emphasis.


Again, very clear peaks and valleys in the waveform. I never cared for the Pipes of Peace album, but then I realized it was because I was listening to it with pre-emphasis, without proper de-emphasis...
 

Rudy

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It was a strange technology for sure, and it primarily was used on discs from the very earliest years of CDs. Whatever its purpose was, it never really caught on.

I've used dBpoweramp for years to rip CDs, and it is able to detect not only pre-emphasis (and give an option to use a DSP filter to counteract it), but it can also find discs or tracks that are HDCD-encoded, where it gives us the option to save it as a 24-bit file. (There's a lot more technical explanation behind it.)

I have to say that the original LP of Thriller always sounded good and wasn't weak in the bass. The original Columbia SACD is supposed to be the closest representation of the master tape. Ripping SACDs was a revelation for me, as I can play the DSD files back through the system without having to downsample them.
 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
Ripping SACDs was a revelation for me, as I can play the DSD files back through the system without having to downsample them.
One day I hope to learn how to do that for my Carpenters SACD!

I learned recently that pre-emphasis is a thing on all vinyl records, but it's because the process of a diamond being dragged through a vinyl groove causes a lot of harsh noises on the high end without any processing. So all records are mastered/cut to have not so much bass and a lot of treble (like CD emphasis), but upon the stylus traveling through the groove, the amplifier boosts the base and cuts down the treble, which softens the music's high end but also softens a lot of the hiss/clicks that are in the groove. (RIAA Curve: The 1954 Turntable Equalization Standard That Still Matters) I believe the same is the case with cassette tapes, because the metal can cause a lot of hiss without noise reduction on the high-end.

No idea why they'd apply the same concept to CDs, though...
 

Rudy

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I think the term pre-emphasis first started with cassettes. Prior to that with reel tape and records, there were different but standardized equalization curves. My dad's hi-fi from the 1950s had four curve settings, and the RIAA curve was the one that won out over the others. I know that for tape, there was an NAB curve (National Association of Broadcasters), but there may have been other curves for that as well (especially for home/consumer use).

Cassettes used different pre-emphasis settings for Type I tapes (ferric oxide), which was 120µs (micro-seconds). Type II (chromium dioxide) and Type IV (metal) used 70µs. (There was briefly a Type III, "ferri-chrome" tape that combined Type I and Type II formulas, but it never took off. It was also 70µs.) Cassettes, having a less tape to work with (both in width, and in linear velocity--1⅞ inches per second vs. much faster speeds with reel tape), were noisier. Because Type II and IV tapes could have more high frequency output, they could be cut slightly to help mask some of the tape hiss.

The Dolby B noise reduction also attempted to help with that, and eventually Dolby C and Dolby S came along to improve on it. (Dolby HX was not noise reduction, but an automatic bias adjustment to the tape to help enhance the treble at lower levels.) dbx noise reduction was a failure on cassette due to the amount of noise--dbx exhibited a lot of "pumping and breathing" that you'd hear when there was a lot of midrange content but little treble content. I gave it a few tries in my own setup and quit using it.

As for ripping CDs, you would need to find specific player models that can use the modification to allow them to send the data over the network to a computer with the appropriate programs installed. For a single use, it's not worth it. Plus, you would need a system capable of playing back DSD files, or convert and downsample the files to PCM digital. There is a long thread over at the HiFi Haven forum with information.

 

Cuyler

Bright colored pinwheels go 'round in my head.
Thread Starter
Got a couple more pre-emphasis CDs, both Paul McCartney… “Tug of War” and “Pipes of Peace.” On “What’s That You’re Doing,” there’s a lot of percussion going on in the left channel that I never heard before. De-emphasis absolutely needs to be applied (liberally imho) here because both of those albums are very heavy on the treble, even without emphasis.
 
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