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Weird low-quality CD: WTF?

Posted: 2005-08-17 10:42pm
by sketerpot
Years ago, I got a CD called The Very Best Of The Seekers, and the music is pretty nice to listen to. When I got it originally, I played it on a couple crappy computer speakers, and I didn't notice a problem. I forgot about it for a year or so, and in that year I got some nice $20 headphones which have far superior sound quality to those crappy speakers.

I got out my Seekers CD today and started playing it with those nice headphones, and I noticed some odd things:

1. The thing is loud. It's louder than all my other songs. It's louder than fucking Metallica. How do they get a CD to be so loud, and why? I have to turn down the volume to listen to the damn thing. :x

2. The sound quality is atrocious. It's CD audio in standard Red Book format so it should have less compression issues than MP3 files which sound much better. It has a sort of staticky sound, and it gives me a headache.

Do any audio buffs around here know what might be the problem with this CD? Was the recording just really shoddy? That shouldn't be the case, since one of the songs on there Georgy Girl was big at one time and I would expect decent audio from such a popular song. And what's the deal with the loudness?

Posted: 2005-08-17 11:17pm
by aerius
You've just experience the joys of dynamic compression, peak limiting, and clipping. What this means is they use sound editing tools to boost the average loudness of the CD. In music terms instead of the music going from pp to fff, it's now all f to fff. All the quieter parts get boosted giving a much louder overall volume.

This is a side effect of the Loudness Race (lots of info on google), where in short the record companies want their CDs to be louder so that they'll get noticed more. Unfortunately it completely fucks over sound quality, especially when idiots overdo it and end up clipping the signal and over using peak limiters which has the same effect. Clipping is just that, the top & bottom of the signal get clipped off caust the dumbass boosted it too much and you end up with a pseudo-square wave. Which sounds nasty.

Pisses me off big time, because there's no way for the consumer to go back and fix it. If the record companies make a CD that's too quiet, I can turn the volume up or rip it to my computer, edit, and burn it, but once the dynamic compression's done, it's unfixable unless I can go back to the raw unmixed tapes.

Posted: 2005-08-18 12:37am
by Uraniun235
Same thing happened to the Pirates of the Caribbean soundtrack. That pissed me off something fierce, I mean really, who the hell needs to fuck with a movie score?!?

Posted: 2005-08-18 01:33am
by The Jazz Intern
Aye, I have not had this problem with any of my music CDs.
All 4 or five of them
(And I call myself a musicain! :? )

Posted: 2005-08-18 10:17am
by aerius
Uraniun235 wrote:Same thing happened to the Pirates of the Caribbean soundtrack. That pissed me off something fierce, I mean really, who the hell needs to fuck with a movie score?!?
I ran a few clips off that through Cooledit Pro a while back when Durandal mentioned hearing problems with the CD. It was not pretty. There were flattened waveforms everywhere, they clipped it all over the place and then they normalized the peaks to 99% so that software wouldn't pick them up as clipped samples. Fools the computer, but not the eyes and ears.

Posted: 2005-08-18 11:45am
by Uraniun235
aerius wrote:There were flattened waveforms everywhere, they clipped it all over the place and then they normalized the peaks to 99% so that software wouldn't pick them up as clipped samples.
Why? Why do they have to be evil?!? Image

Posted: 2005-08-18 03:48pm
by aerius
Uraniun235 wrote:Why? Why do they have to be evil?!? Image
Because they're the music industry.
Because you touch yourself at night.
It's the unwritten rule.

Posted: 2005-08-18 05:00pm
by Darth Wong
Another possible source of sound quality issues may be copy-protection schemes. There are a number of schemes out there, and the music companies do not feel obligated to tell you if they are using them. I know one scheme in particular tries to "game" the most common MP3 encoding algorithms by deliberately introducing digital noise which is designed to cause severe problems with the encoding algorithm. It can also cause audible degradation of sound quality, but according to the music companies, it is "within acceptable levels". Whatever the fuck that means.

Posted: 2005-08-18 05:03pm
by Pcm979
Crap, I really like the Pirates of the Carrabean soundtrack. Is there a place to get them without this futzing?

Posted: 2005-08-18 06:30pm
by muse
Pcm979 wrote:Crap, I really like the Pirates of the Carrabean soundtrack. Is there a place to get them without this futzing?
You'll have to wait until someone gets around to remastering it. I'm told that some of the Japanese market CDs are done with more care since the people there are more dicerning with regards to sound quality.

Posted: 2005-08-18 07:56pm
by aerius
Darth Wong wrote:Another possible source of sound quality issues may be copy-protection schemes. There are a number of schemes out there, and the music companies do not feel obligated to tell you if they are using them. I know one scheme in particular tries to "game" the most common MP3 encoding algorithms by deliberately introducing digital noise which is designed to cause severe problems with the encoding algorithm. It can also cause audible degradation of sound quality, but according to the music companies, it is "within acceptable levels". Whatever the fuck that means.
"Acceptable levels" means you can't hear it on a boombox, car radio, or Bose products. I don't own any watermarked CDs and hope I never do. I have heard a few however and the artifacts are noticeable on a decent stereo system or headphones. Effects are fairly mild compared to the evils of dynamic compression, but once you pick them up it'll annoy the fucking hell out of you and your mind can't block them out.

Posted: 2005-08-18 09:23pm
by Saurencaerthai
Image
Take one of these.
1. Select the compression ratio of either 20:1 or "Nuke"
2. Turn up attack.
3. Turn up gain.

Enjoy all that is modern dynamic smashing, one of the greatest travesties of modern recording.

Posted: 2005-08-18 11:37pm
by aerius
A little picture to illustrate what dynamic compression looks like. This is actually a pretty mild 4:1 compression as done with Cooledit Pro.

Image

On the top you see the original waveform, notice how it has peaks and dips all over the place. Some places it's loud, some places it's quiet, that's the way things naturally sound. The peaks are when drums get hit or trumpets come in, and the quiet parts are where the singer sings softly, breathes between words and deliberate silences in the piece.

The bottom one is after dynamic compression. A lot of the peaks and valleys are gone, everything's at a more uniform level. The peaks where the instruments hit are swamped, and some of the quieter parts are drowned out. Pay special attention to the end. Look at the original and how it slowly fades into silence. Now look at the compressed one and see how much louder in level it is and how sharply it fades away. The decay is just not natural.

Posted: 2005-08-19 12:04pm
by SyntaxVorlon
...Those Fuckers.

Posted: 2005-08-19 07:31pm
by Saurencaerthai
aerius wrote:snip
In one of my recording classes, we loaded two songs into Protools so that we could see the wave forms. The first was a Livingston Taylor song, full of peaks and valeys. The second one had us guessing, though. It was a solid block of wave all the way through. Initially, we thought it was some sort of death metal or the like. It turned out to be the tune "Smooth" by Santana.

Posted: 2005-08-19 10:22pm
by aerius
Santana's Supernatural album is one of the most horribly compressed albums ever made. One of the stereo magazines ran the tracks through their sound editing software and found it had something like 3dB of dynamic range. They also showed the waveforms and as you said, it was a solid block all the way through. Not surprisingly, it sounds like crap on anything better than a boombox.

Posted: 2005-08-20 12:33am
by Einhander Sn0m4n
Isn't dynamic compression also the reason why TV programs sound [like this] and car commercials (they're always car commercials too!) sound [like this] despite both having the same peak decibel level?

Posted: 2005-08-20 01:24am
by Darth Wong
Einhander Sn0m4n wrote:Isn't dynamic compression also the reason why TV programs sound [like this] and car commercials (they're always car commercials too!) sound [like this] despite both having the same peak decibel level?
Yes. Dynamic compression allows you to raise the average sound level, which will increase the subjective perception of volume. But it also makes the music sound like shit, because in reality dynamic range is what gives music its punch and expressiveness. Without dynamic range, it's just a wall of noise.