Quote:
Originally Posted by
johannburkard
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Reviving this thread: Is there an easy way to visualize and quantify FIR pre-ringing in VST plugins?
Yes. Time behavior of equalizers is well described in impulse response snapshots. Use something like RXs reconstructed waveform view to get an idea of what your DA converter does to represent those sample points.
A perfect impulse is zeroes only with a single sample at max level. Leave enough time around the lone peak to capture the event you’re looking for. Run this through any process and the output will be the IR for that system.
Normal EQs will only show things happening after the excitation impulse. Linear phase will have equal amounts of activity before and after the impulse. Mixed phase will (usually) have more happening after the impulse, and some things happening before the pulse.
The quanta you’re looking for is the RMS value for the before/after parts. Linear phase have the same area under curve before/after the impulse. Normal equalizers / minimum phase will have infinite difference as there is nothing happening before the impulse arrives. Mixed phase systems will typically give some lesser RMS numbers for the before parts and larger RMS figures for the after part. The difference between the before/after can then again be used as a ratio for dB figure if you so pleases.