Hello,
I have a question about the number of poles for a Butterworth filter
when there are 2 passes.
When n, the number of poles, is not specified, is the default value of
2 used? Does this mean there are 4 poles with 2 passes when n is not
specified?
Suppose n = 4 and p = 2. Are there 8 poles?
Best regards,
--Sierra