Archive for March, 2007

When geeks get sick

2007 March 15

Recently I was very sick. After about a week of having some flu-like viral infection, I got laryngitis and bronchitis. So what does a geek do when he gets bronchitis? Signal processing of course. I used the microphone built into my laptop and Audacity (a free-ware program) to record my voice and then computed the spectrum. A week later, when my voice was a bit better, I did it again and compared the results.

The “sick voice” is in red. The “healthy voice” is in black. The normalization is probably screwed up, so I think that the black curve should be overall higher, but it’s still a fun comparison. Notice the how the “sick curve” has less energy in the high frequencies, but a little more energy in the mid-frequency range. The high-frequency cut-off really happened: trying to talk, my voice kept cutting out completely any time I tried to raise the pitch higher than a certain point.