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Topic: odd behavior in decimate
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Posts: 1
Registered: 9/10/13
odd behavior in decimate
Posted: Sep 10, 2013 1:46 PM
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If I run this command:
(n is the IIR filter order for anti-aliasing)
I get reasonable results for n=3,5,7,9,11,13 (random-looking hash, on the order of 1e-7 or smaller)
However, if I use n=2,4,6,8 there is a significant DC error in the signal (values around -0.0114). n=10,12 gives a similar result to the odd orders.
It looks like there may be some odd DC behavior with the Chebyshev type I filters at even orders <= 8. If so, this makes the TMW default of n=8 a little scary.

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