I admit it, I'm fascinated by what motivates people to click those Plus and Minus recommendation buttons that appear at the bottom of our stories. Take Kirk McElhearn's Convert iTunes Store Music Files Playlist blog from the other day. As I write this, it's one recommendation up--24 Yes, 23 No. What is it about converting iTunes Store music files that sparks these kinds of conflicted feelings?
A read through the comments enlightened me. Some readers were offended by the suggestion that it's perfectly okay to convert 256kbps AAC files to MP3 files at that same bit-rate. Given a few of the reactions, you'd think Kirk had slapped someone's favorite Aunt.
"Save our precious ears! It burns! It burns!!!"
As someone with perfect pitch, I understand that not everyone is issued the same set of ears and audio acuity. But when declaring that I can tell the difference between an Eb and a C, I can actually prove it by listening to a pitch and naming it. I rarely see this kind of proof from those who claim to be troubled by the audio degradation that comes from converting a file from one lossy compressor to another.
And thus the title of this blog. By that title I mean, put yourself to the test. Using whatever audio equipment you prefer, take a handful of tracks from some favorite CDs and rip them with different settings--Apple Lossless, AAC at 128- and 256kbps, MP3 at 160- and 256kbps, and MP3 at 256kbps converted from an AAC file encoded at the same bit-rate--and set up a blind listening test like so:
One comparison track will be the Apple Lossless version. A second comparison track will be one of the files ripped with a lossy encoder. Have a friend play one and then the other. Switch back and forth a few times. State which is which. Repeat a few times so that you help eliminate chance. Repeat with other tracks. Where do you hear the differences? (Cymbals are a good place to start.)
Or, to help determine where transparency kicks in for your ears (the point where you can't tell the difference between the lossy and lossless version), rip your tracks at several bit-rates--from 256kbps on down to 96kbps. Conduct the tests and see how you do.
This guide and its references will help you get started.
When you can reliably find that point of transparency, then you've got something to talk about. Until then, you're just another person with an unsupported opinion.
I make this suggestion not simply because I'm weary of all the skirt raising over encoders and bit-rates, but also because determining what one can and can't hear may be beneficial to listeners. For example, do you have a hankering to upgrade your purchased protected iTunes tracks to iTunes Plus simply for the alleged audio-quality bump? If I were staring down an entry fee of a couple of hundred bucks to do that, I'd take the time to find out if I really can hear the difference. If I can't, I've saved a significant amount of money. And hell, if I can't tell the difference between an original protected track and one burned to CD and then reimported to remove DRM, I've avoided the whole iTunes Plus upgrade issue--my tunes are free of DRM and ready to use where I like.
Additionally, you can celebrate the fact that you're a cheap audio date. If you really can't tell the difference between a 128kbps AAC file and one encoded at 256kbps, you've potentially doubled the number of songs you can fit on your iPod. Sure, you don't have the bragging rights of those with golden ears, but, in the end, you've got a longer playlist. And sometimes it is about quantity rather than quality.
This story, "Listen- (or Shut-) up" was originally published by Macworld.