Have you ever wondered what a synthesizer and a percolator have in common?
The better the filter, the better the result.
When I told my friend Carlos that a good synthesizer filter should be bubbly and sparkling he answered, “what the h**l are you talking about??” I think that a good sound is better than a thousand words, so I recorded him a small example of an analog filter in action.
The sound above shows a single note which is being played all the time while I use a Low-Pass filter to modify its harmonic content. I adjusted the resonance of the filter so that it emphasizes the filter’s cutoff frequency, which allows you to go over the different tones of the harmonic series (it really does, but I tweaked the filter’s knob by hand, so it’s not very precise). After this long sound I also included a short sample where the filter sweeps quickly, so that you can hear that luscious, bubbly quality I was talking about… which reminds me that my coffee is waiting! 😉
If you are interested in how a typical analog synthesizer works, this tutorial should be a good starting point.
ps. A thousand kudos if you can tell which synthesizer I made the sound with.