Increasing the delay on the second term of the ``simple lowpass
filter'' can be seen as replacing that term with a delay line,
yielding
where
is the coefficient multiplying the delay.
Figure 14:
A feedforward comb filter.
![\begin{figure}\centerline{\scalebox{1}{%
\input{ffcomb.pstex_t}}}\end{figure}](img196.png) |
Figure 15:
The comb filter magnitude response.
![\scalebox{0.7}{\includegraphics{eps/ffcombg1.eps}}](img197.png) |
The name of the filter comes from the fact that the magnitude response
resembles the teeth of a comb, and because there are not feedback terms.
``Mus 270a: Introduction to Digital Filters''
by Tamara Smyth,
Department of Music, University of California, San Diego.
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Copyright © 2019-02-25 by Tamara Smyth.
Please email errata, comments, and suggestions to Tamara Smyth<trsmyth@ucsd.edu>