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At 07:18 PM 7/5/2004, Alex Matulich wrote:
>> But your filter seems to become unstable with small values of Length.
>A positive way to look at this is, a length of 6 in this critically-damped
>filter is equivalent to a length of about 2 in XAverage or T3 -- all will
>have a 3 dB cutoff wavelength of 6. So a 6-bar critically damped filter
>is similar to a 2-bar moving average, which is probably as small as one
>would need.
You could probably figure out a modification to keep it stable but restricting the length to > 6 would not be a bad solution.
The four pole version (Passes = 2) has a frequency response that drops smoothly at 24db per octave as advertised and the step function response shows no tendency to overshoot, as advertised.
I tried posting a picture but the Omega-list size filter blocked it again. Perhaps the management could increase the size limits for attachments to something like 100KB so we could post more pictures. I would think most people have high speed Internet connections now days...
Bob Fulks
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