My computer is rather busy today (AAC->MP3)

I have several road trips coming up in the next few weeks (LA, Sacramento), and I wanted to burn myself some MP3 CDs with good driving music. Unfortunately, when I ripped the bulk of my CDs into iTunes, I did so using AAC encoding. I guess I was trying to optimize space. Oops.
Anyway, yesterday I created a “Smart Playlist” in iTunes with the following properties:

  • “Kind” includes “AAC”
  • “Kind” does not include “protected”

This gave me a playlist with 7,467 entries. I selected the whole list, and told iTunes to convert them from AAC to MP3. This will create 7,467 new items, of course, so when everything checks out I’ll delete the AAC files.
So far it’s been running for about 14 hours on my 1.83GHz Mac Mini, and the iTunes folder on my external 1TB drive has grown to 155GB. Conversion speed seems to be 45-50x…
(And yes, I did back up my iTunes library!)
UPDATE: The final glitch was tricky: how could I use the smart playlist to remove tracks from my iTunes library? “Delete” simply removes the tracks from the playlist! The answer was to select all tracks in the playlist, right-click, choose “Get Info“, and change the “Artist” for every track to “Zzzzzzzzzzz“. This took a while to run… Then I went back to my library, chose “Zzzzzzzzzzz” from the Artist list, selected all of the corresponding tracks, and deleted them. There has to be an easier way… such as an Automator script?