Comb Filter to effect a frequency and its harmonics!

After I did all that work described in my last post, my friend Jerry emailed to tell me that you can effect a frequency and all its harmonics at once with a Comb Filter. Sure enough, once I knew the name I looked for Comb Filter and found that David R. Sky, the same guy that designed the Nyquist-language Notch Filter that plugs in to Audacity has also designed a Comb Filter for it. I have now downloaded the comb filter and installed it the same way I did the Notch Filter. It can be found at: http://audacity.sourceforge.net/download/nyquistplugins

I don't have time to play with it right now, because I have to do my content editing tonight, but next time I'll try that first.

Here's what David wrote about it on the Sourceforge download page:

Comb filter | View comb.ny | Download comb.zip

Example audio clips: [MP3 Clip 1]

The name 'comb' filter comes from how it acts on the audio spectrum of what it's applied to: it looks like a comb with the teeth pointing up. For example, if you set the comb frequency at 1000 Hz, the comb filter emphasizes 1000 Hz as well as 2000, 3000, 4000 and so on Hz. This particular plug-in produces an 'airy' effect, which is more pronounced the higher the comb decay value is set, and resonance is increasingly produced as well.

A comb filter can be produced using flanger-like settings on a delay effect, but this filter does not use a delay to get the result, so it does sound somewhat different.

Written by David R. Sky