Two-armed typing, MP3 fidelity testing

The arm is slowly healing. Have discovered that if I take off the sling I can use the right arm to hoist the left onto the laptop keyboard, where it receives enough support to allow me to type two-handed. I can’t do it for a long time, but it will help me dig out of the backlog and start getting productive again. One-handed typing is NOT 50% of two-handed typing, because you have to move your arm back and forth over the keyboard and have to look at all the keys. Two-handed is about four or five times faster for me.

Mike and I have been talking about finally coming to an unambiguous conclusion about optimum MP3 bitrates – we want to find the rate at which MP3 is indistinguishable from the source CD. Neither of us are tolerant of MP3 compression artifacts and neither of us care about keeping files small enough to trade over the net – we just want as much compression as we can get without compromising a drop of fidelity.

I’ve done some experiments before, but we’re going to do this one right. He brought over some of his best hi-fi selections, including some of the RCA Living Presence stuff. I contributed three of my own favorite fidelity test tracks, and used my little TestEnc script to encode six sample tracks at a variety of bitrates with the lame encoder. Then I burned those tracks back to audio CD. This returns them to PCM, but with the compression losses now built in.

The weak link in the chain is Be’s built-in decoder which I’m forced to use to translate from MP3 back to PCM when burning the disc. It’s based on blade, which is OK, but definitely not the best, and certainly not what I would use for a test like this given my druthers. If I suspect it’s getting in the way, I may have to do this in Windows with CDex or something that lets me choose the decoder.

Before burning, I randomized the track orders and printed out a key listing all the actual bitrates. Folded this up and sealed it. I also printed out track lists w/o bitrates and we’ll use those to write notes about our impressions. Tonight I’ll take these to his house and listen to them on his system, skipping around between the track variations and making notes. We’ll see how the notes compare to the key page.

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