The slow death of sound quality.

Buy CDs where you can. Really, unless there is no other option, don't buy albums online as mp3s.

Why? Good question.

I was over at my dad's the other day, and we were talking about music and the amazingness of technology that allows us to store a thousand songs on a device not much bigger than a credit card. There is, of course, a trade off, my dad tells me, and he generally knows these things. The technology behind sound has been pretty much his life's work. 

The main problem is file size. A track taken from a CD is fairly substantial. To transfer that file to mp3, it is compressed considerably. Anyone who thinks that there is no loss of sound quality is deluding themselves. That extra information has got to go somewhere... A zipped document is compressed by taking out the white bits; something in the program remembers where they should be and puts them back when you unzip the file. There aren't any "white bits" in music, so when a music file is compressed, the program takes out what it considers to be extraneous material - most of it is not obvious to the casual observer, but it is there for a reason. That reason is something called soundstage. I can see your WTF expression from here, so let me explain:

If you have ever listened to a really good stereo recording, on a good stereo, through good headphones, you can "hear" where the instruments are around you. You can close your eyes and think "the drums are behind me, the bassist is off to the left and slightly in front, the lead guitarist is to the right, and the singer is straight ahead". I remember this happened to me for the first time when I was 12, and I was so astounded by it that I've never forgotten. This all goes away in mp3s - if you listen for directionality, all you will be able to work out is 'inside your head'. There is still stereo, so you get a bit of left and right action, but the rest of it gets lost in the ether. 

Don't despair, it doesn't mean that you are never going to enjoy listening to your iPod again! When dad told me about this, I thought "oh yeah, you're right!", but I hadn't realised it until he told me. I did an experiment, listening to the same couple of songs from a cd on a cd player, and then via Media Player (which is the same as listening to them through iTunes or similar). The difference is definitely there, but you do need to do a comparison to really hear it.

So why bother? If the difference is not that great, why worry about it? Trouble is, the vast majority of people are never going to know that the music they are listening to is slightly inferior in quality - they are listening to the song, not the minute nuances in the music (and considering some of the crap that the kids consider to be "music" these days... Kanye West and pals, I'm looking at you guys here), so they are never going to know. But, if everyone buys music online, then eventually that will be the only way to buy music, and then the opportunity to buy good quality sound will be gone for good. The saddest part about this is that, for the most part, no-one will even know.

Of course the other thing about cds - if your hard drive crashes, you still have all your music, you just have to go through the rather tedious process of uploading it again.

Mp3s are great - I have bought many of them, but if I want more than a single song by a particular artist, I will always buy the cd. Music makes life better, why should we try to make music worse?