Hi! I'm developing an audio plugin that needs to perform some oversampling and low-pass filtering to reduce the aliasing brought by some non-linear processing. I'd also like to keep the phase response flat-ish for a frequency as high as possible.
I was looking into different plugins for comparison and I noticed some developers having an interesting anti-aliasing filter phase response, where the phase shift is highly non-linear, but pushed closer to the cutoff frequency with respect to a classic high order IIR (Ellitpic, Chebyshev & co.).
Is anyone familiar with this type of sharp filter? I researched on brickwall and half-band filters but couldn't find anything with a similar phase response. Can it be a more complex scheme involving all-pass filtering for a "better" phase response?
In the images below there is a comparison between an Elliptic filter (red) and the one that I can't identify (yellow). For an almost identical magnitude response (except the overall level), the phase response is very different.
Thanks!
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I was looking into different plugins for comparison and I noticed some developers having an interesting anti-aliasing filter phase response, where the phase shift is highly non-linear, but pushed closer to the cutoff frequency with respect to a classic high order IIR (Ellitpic, Chebyshev & co.).
Is anyone familiar with this type of sharp filter? I researched on brickwall and half-band filters but couldn't find anything with a similar phase response. Can it be a more complex scheme involving all-pass filtering for a "better" phase response?
In the images below there is a comparison between an Elliptic filter (red) and the one that I can't identify (yellow). For an almost identical magnitude response (except the overall level), the phase response is very different.
Thanks!
Statistics: Posted by jacopoeftilo — Thu Dec 26, 2024 8:46 pm — Replies 0 — Views 29