I was listening to an audio book by Brian Tracy recently, and he said that you should always have something educational playing in the car because with the amount of time most people spend in the car, it’s equal to about a semester or two of a college class. Years ago, I learned quite a bit of Russian in the car when I had a long commute but recently, I haven’t been making productive use of car-time.
Part of the reason is that my car doesn’t have an mp3 player. If it did, it would be easy to just put mp3s onto a disk or thumbdrive and everything would be great. Instead, it has a 6 disc cd changer in the trunk and burning the disks for audiobooks can be a chore. There was a time when I would go down to the public library, check out some audiobooks, and then rip them and burn them as mp3s onto a disk that I would listen to at work. Now I can get them much more easily using bittorrent, but I still have the problem of getting them all onto cds. One of the biggest problems is that in my car, I’m limited to 6 disks. Lately, my cd player is skipping a lot, but that’s a problem for another time.
To get around the 6-disk limit, there is a technique that I’ve used for other purposes that can squish the audio into a smaller timeframe without making it sound like chipmunks. It’s been pretty well established that people can understand language in their native tongue much faster than they can speak it. So one productivity technique is to speed up all your audiobooks (and optionally remove periods of silence). I discovered that the ‘sox’ utility can do this, and I’ve used it to speed up audiobooks before. Using sox, you can speed up a long audiobook until it fits on 6 cds. This is done with the ‘tempo’ option. Here’s the command.
sox -t mp3 $file -t wav - tempo 1.25|lame -b 128 - $output
What I’ve done here is to play the mp3 file ‘$file’ at 1.25 times regular speed and then send it as a wav file to lame to be encoded at 128 kBps and saved as the file, ‘$output’. I think there is an option in sox to save directly as an mp3, but that doesn’t seem to work with my distribution, so I use the method above. You’ll want to calculate the tempo needed for your particular situation, and then test the new files out to make sure they are understandable. In my experience, a tempo of under 1.2 is usually fine but beyond that things start to get dicey.
Sometimes, the mp3 files I have are long and I decide that splitting them up into smaller files would help me use cd disk space more efficiently. For this, I can use the wonderful ‘mp3splt’ utility. I use this pretty often for various audio projects. Here’s a command that will split a file into 2-minute files named file001.mp3, file002.mp3, etc.:
mp3splt -t 2.00 -a -o file%n filetobesplit.mp3
The number after ‘-t’ represents 2 minutes and the ‘-a’ tells the program to use automatic silence detection. This way, the splits will occur between words rather than during them. Thus, the files will be a little longer or shorter than 2 minutes. The ‘-o file%n’ tells the program how to name the resulting split files.
So with these utilities, you can scrunch long audiobooks into a length that will fit on 6 cds (~480 minutes). Or you can srunch it up even shorter so you can listen to it as fast as you can understand it. Now, even if you don’t have an mp3 player in your car, you can productively listen to audiobooks.



