Addicted to Fun and Learning
- Dec 31, 2018
Is it to be expected that adding a 20Hz highpass filter spoils rms PKEM big time?
Ya, if it change the envelope and the signal has appreciable energy near cut off, due to the filter phase response (see here and here). If comparing two time files (envelopes), it'll create deltas that aren't audible.
That's a danger with time comparisons alone. Transfer functions that introduce all pass phase response anomalies can distort the envelope but not be audible.