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       You download music. At random, you download a song that sounds "wrong" somehow, or just utterly like crap. You rip your CDs and suddenly find your hard drive has filled up faster than a supermodel at a fast food resturant. You wonder if those subscription music services or pay download sites are worth it.
       The SoS MP3 Project is your answer. As more and more people deal with music in digital form, the issues of quality and compression become increasingly important. Here's our guide on what you need to know, with audio examples of what we're talking about here.


What is Compression?
       The thing that makes MP3 technology so popular is its ability to fit high quality sound into a rather small file by compressing it. Compression involves squeezing a file down with as little loss to quality as possible, using mathematic algorithms and special computer magic dust to make it work. In other words, it doesn't really matter HOW it works for must of us, just that it does.
       What you do need to know is the numbers. Generally, the higher the number in kbps or kb for a music file, the better it is going to sound. Also, the higher this number, the larger the file will be. The general range for MP3 files is between 320 Kbps and 8 kbps. 320 will give you just about max quality that only a true audio snob would scoff at. (And since your ears are more likely than not damaged due to years of loud music, 320 will count as perfect to you.) 8 kbits is a really small file, but it sounds like crap. Literally. If you could somehow convert crap into audio form, 8kbit music would be it. (N'Sync at 8kbits would be considered diarrhea.)

While you consider that lovely image, glance over this table of common compressions for reference:

Compression Quality Size
320 UberCool UberHuge
256 Pretty Damn Good Fills the hard drive pretty quick.
128 Average/Good Close to about a Megabite (Mb) for each minute.
96 Mildly irritating But I can stick 5000 of them on my Ipod!
64 I like listening to the music on AM Radio. And I have a small hard disk.
(Remember kids, it's not the size
that matters, it's how you use it.)
32 I only listen to loud indistinguishable noises anyways. I transfer music via floppy discs.
16 and
below
Music? No seriously, what's music?

So What Do I Do?
First, you need to check what quality your music is from now on. A good rule of thumb: Stick to 128k. You get the most bang for your buck (even though you probably downloaded the music for free, you dirty pirate! Arrgh.) Anything below, and you have noticeable loss of quality. Anything above, and you better make sure you have a big hard drive. So here's the easy way to figure out what the quality is:

Windows Media Player:
See the Red Circle?

WinAmp
WinAmp is better than Windows Media.

When Downloading from Kazaa, etc:
128 all the way. 96 and I hurt you.

A couple notes: When using a download program, weird numbers that are uncommon usually mean bad quality or a messed up file. Don't go for them. And if you download a file and the number fluctuates randomly, you it's generally okay, but it may be an indication of a bad file. Also, if you are paying for your music, you better demand top quality. Don't get ripped off. 128 in these cases is the bare minimum. But it should be a higher quality.

Examples?
There are certain things to keep in mind. Although the rule of thumb is 128, you may have specific needs for certain situations. For instance, people with less memory may want to know how low they are willing to go, or people preserving their CDs may want maximum quality. So here I will provide comparable clips of music for you to judge on your own. A key judging point if you are tight on memory is to figure how simple the song is. The less unique sounds and instruments in the music, the less difference you'll notice as the quality drops.

Right Click the Link and select "Save Target as" to download each clip so you can compare them to each other closely.

Simple Music Compressed: Download 30 second clips of a simple music piece (only consists of vocals and guitar) recorded by Sean Lucy. (Song: Shallow Sea.)
128 kbitsYup, it's the song. Good quality. Or as good as it was recorded.
64 kbitsAt 64 kbits, close observation reveals a slight loss of quality, but due to the fact that there are only 2 sources of sound, it handles this cut well. Some of the guitar quality is lost, however.
32 kbitsHere we notice a loss of voice quality, and the guitar sounds decidedly muffled. The yelling towards the latter half of the file still stands up.
16 kbitsKinda sounds like I stuck my head under a pillow. The guitar is very muddled and indistinguishable, the voice has lost almost all of its dynamic.
8 kbits And now we've stuck our head under water. Guitar sound is almost utterly destroyed. Voice is nearly incomprehensible.

Now let's kick it up to a more complex song, then end it with a full out studio song. This next song is Is another SL Recording of the song Phone. It has drums, guitar, bass guitar, and vocals. Notice how much quicker it degrades in quality.

128 kbits Drums, vocals, backup vocals, screaming guitar, bass guitar. Holy Crap! Sounds like music to me.
64 kbits Already you can notice the drums lost most of the dynamic of their sound, and the vocals don't stand up to well either. The Bass Guitar is fine, and the guitar loses a bit of its edge.
32 kbits Drums are terrible, guitar becomes instantly muddled, the beat is lost, and vocals lose all their sharpness. Bass guitar has disappeared almost entirely.
16 kbits The quality gets so horrible now it's just noise. Although in the beginning the drums do sound kinda cool.
8 kbits The distortion is so heavy now, that it's actually more distinct than the music itself.

Even then, those songs were recorded using just a regular PC. Studio quality recordings are painstakingly edited to get rid of extraneous noises, accentuate certain instruments at certain times, and generally impress you. The artist(s) paid good money to make things come out just as they wanted (which is why the sudden controversy over music swapping has occured, you can easily duplicate high quality music an infinite amount of times as long as it was compressed correctly the first time.) It'd be a shame to see what would happen if one of these painstakingly crafted pieces of music were put through the same process, eh? Well, people trade music of this quality anyways, and others may even be duped into buying it. So here I've taken a 30 second sample of Maroon 5's "Harder to Breathe," to which the full song can be downloaded for free here at MP3.com.

128 kbit Hard drumming, short bursts of guitar, vocals, all nice and clean. Very sharp and distinct sound.
96 kbit Even just dropping it to 96 kbits instead of the 64 from before shows a marked difference in song quality. The clarity is lost, along with some of the sharpness. The drums are most effected. You may or may not mind this.
64 kbit Dump it down here and already the drums sound like crap, and there's a lot of irritating background noise. The vocals lose fidelity. Imagine trying to turn this up.
32 kbit Background distortion, further deterioration of the drums, the guitar gets muddled.
16 kbit What the heck is this? It's terrible. All that hard work, lost. The song is ruined.
8 kbit This isn't even recognizable of music, and the distortions even flow into the lyrics, altering the pacing of the song.

Now do you believe me? Good. The same degradation you noticed also happens when you drop from 320, to 256, down to 128, but as I said, unless you're a real audio snob, or it's one of your favorite songs with real complex instrumentation, you won't notice unless you turn it way up. The final point is, if you are going to rip your CD collection for computer storage, or for playing on an MP3 player, you want to go for as high quality as possible. Every CD ripping program you have allows you to control the compression rate of the music. (Our tech-man Fraxyl recommends ripping CDs using CDex, a free program.)

Now you know, so stop sharing low quality music, or making your friends listen to a "really cool mix CD" you made of crappy sounding music (at least quality wise. Music taste notwithstanding.)