Does Higher Bit-Rate Music Sound Better?

When you rip music from CD, you're asked to make many choices: compressed audio format and the bit-rate of the compressed file being the chief among them. This latter choice is a biggie: Do you want, as iTunes would have you believe, "good quality" at 128kbps, "high quality" at 160kbps, or "higher quality" at 192kbps? Or something even higher? Or do you want wholly uncompressed files, which keep every bit of data on the original recording?

This selection isn't just critical because it can affect the quality of the audio you ultimately hear. It's also a big determining factor in the size of the file. A four-minute song encoded at 128kbps will consume about 3.7MB of space. That same song at 192kbps will eat up 5.6MB and a whopping 10.5MB at 360kbps. On a 20GB iPod, that means you can store about 5,000 128kbps songs but only 1,750 360kbps songs.

So, the big question... what does bumping up the quality of a music rip get you? Maximum PC took a bunch of non-techies, outfitted them with headphones, and ripped their own music at 160kbps, 320kbps, and a lossless format. The editors then asked each tester to blindly listen and rate the tracks as good/better/best... the idea being that the lossless track should sound much better than the lowly 160kbps track.

How do you think they did?

Not very well. Each of the testers got some right and some wrong: But most testers were simply unable to tell the different between a 160kbps track and an uncompressed one at all. Whether that's because encoding works better than we all think or because our ears are universally busted, even lower-grade digital music is still good enough for most eardrums.

One takeaway from the Max PC piece: variable bit rate recording makes a huge difference. You can turn this on in iTunes by using a "custom" encoding setting and checking the "Use Variable Bit Rate Encoding (VBR)" box.

Try the experiment for yourself sometime and see what you think. In my experience, the quality of your headphones is much more important than the way the music was encoded.