Re: Noise removal technique described (was: Filtering out jet planes

["Dan Dugan" dandugan_1999]

Andrew, thanks for the great tutorial example and illustrations. On a
general note for this kind of work:

Dividing the low and high frequencies for separate processing, and
substituting clean low frequency ambience from another part of the
file, are processes identical to the "crossover" filters used to
divide the frequencies between woofers and tweeters in a speaker.

It isn't necessary to use "brickwall" filters for this function; lower
order filters (like 12 dB/octave) may have less phase shift away from
the crossover point, and recombine more accurately.

-Dan