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Is iTunes or Windows Media Player destroying your music?

This has been coming up frequently lately, so I decided to post my usual soapbox here. iTunes and Windows Media Player are great tools, but if you’re not aware of how things are set up, you may be actually hurting the quality of your music.

 

Everything in our computers is geared nowadays for communicating over the internet. The most common format for music is the MP3 file. It’s great for sending in an email and it sounds pretty good. When you place an audio CD in your computer, iTunes or WMP may automatically “rip” the digital audio tracks to MP3 files for you. Here’s what that means.

 

A track on an audio CD is actually a special digital file that is comparable to a WAV file on a PC or AIF file on a Mac. Technically, it has a 44.1kHz sampling rate (a snapshot of the sound is taken every 44,100 times per second), and is sampled at 16 bits (every snapshot is described as a digital word that is 16 characters long). It takes up about 10 megabytes per minute of music, so for a 3-minute song, that’s about 30 megs. That’s way too big to send in an email.

 

The best sampling rate for a music MP3 is the same sampling rate for the CD – 44.1kHz. The bit rate is the amount of data that is streamed per second – the higher the bit rate, the better the quality, and the larger the file. The lowest acceptable bit rate for music MP3s is 128 kbps (kilobytes per second).

 

An MP3 file is a compressed streaming data file based on a “lossy” compression formula. The MP3 convertor uses psychoacoustic tricks to remove over half of the information in a WAV or AIF file. The size of a 44.1kz 128kbps MP3 file is about 1 megabyte for each minute of music, which means a 3-minute song will only take up 3 megs of space. In other words, you’ve lost 90 percent of your content.

Still, it sounds OK, right? Right. Until you forget that it’s an MP3 and decide to burn an audio CD from it. So now the little 3 meg file gets expanded to 30 megs again, because that’s the CD format. It’s lost 90 percent of the information, yet gets blown up 9 times as large. Imagine taking a picture on your cellphone and blowing it up the size of a billboard. The big jagged blocks you would see are comparable to the badly defined audio that is now on your CD.

 

Now your friend gets the CD and puts it in their computer, and iTunes or WMP rips it back to an MP3. Only this time, the MP3 convertor is converting crappy jagged block audio data, and out comes a crappy MP3. You start to hear litle gurgling sounds and wonder where your high end went..

 

The lesson is to always create CDs from uncompressed WAV or AIF files for the best quality. You can change the settings in iTunes or WMP to rip your audio CDs as WAV or AIF or, if you need to save space, choose a lossless compression scheme (Apple Lossless, WMA lossless, or FLAC).

 

Create a separate folder for your MP3 files that you want to add to your player or send over the net, so that they don’t get confused with your best quality, uncompressed files. Or just don’t use lossy compression schemes like MP3 at all if you can help it.