Some of the knocking frequencies were inaudible to an untrained ear. But what if he built a machine with perfect pitch that could hear knock and also ignore false positives. The first line of defense is to determine very accurately when it is true knock and not some other noise, he says. Bizub convinced his boss to buy a 16-channel digital recorder in a music store for $1,200. He also purchased a suite of music software to analyze the spectrum and the frequency of the knocking sounds, and a 64-band equalizer to amplify the inaudible frequencies related to knock. The idea was to capture these sounds as wave files, analyze them with the music software, and plot out whats going on, he says.
I skimmed the article. I fear I’m too stupid to really understand it.
Now if this guy ever works on reed making and finding a way to make the perfect reed, I’ll read more carefully.