Dear Attila,
Thanks for taking the time to answer, unfortunately you misunderstood my question. My question concerned the phase 180° discontinuities which appear in phase in characteristics of higher order filters. Look e.g. in the csv-fragment below:
Frequency (Hz),Channel 2 Magnitude (dB),Channel 2 Phase (*)
67.84039429151049,32.33863058034709,-115.0260967835472
69.41950372042898,32.82012692658842,-116.6902265699424
71.0353698134933,33.35998288920216,-118.4767475993952
72.68884814938258,33.86949926656823,-120.4429189376033
74.38081422193648,34.42710393401945,-123.0032131846593
76.11216390371717,35.01807311003826,-125.6403202728387
77.88381392036204,35.60595461974825,-128.8409191851678
79.6967023359762,36.23069593730597,-132.2874092457207
81.55178904982499,36.83287768063549,-136.609505586391
83.45005630458739,37.4432129685337,-141.4554223529707
85.39250920643975,38.00862023330612,-147.1141472300344
87.3801762572454,38.51766449352777,-153.2963667607696
89.41410989913213,38.89978927587817,-159.9990032507159
91.49538707174641,39.20806992784435,-167.2649998957178
93.6251097824769,39.3679758620025,-174.6532900565014
95.80440568995267,39.38339174460207,178.2076882057428
98.03442870112301,39.29580965462377,171.2321917374081
100.3163595822344,39.08330573023837,164.4734535672866
102.6514065840309,38.77847248087976,158.4707624675104
105.0408060815049,38.4234657631503,153.0376864214749
107.4858232285421,38.00415850907009,147.7992136217931
The value for the frequency of 95.80440568995267 Hz, has such a 180° phase discontinuity. The phase is given as: 178.2076882057428° but I'd prefer it as: -181.7923118...° i.e. the given value (and all following values) minus 360°, that way the phase characteristic becomes continuous.
The strange thing is, that Waveforms is "aware" of this issue as it is possibe to display the phase characteristic without 180° discontinuities by entering an appropriate offset and range.
kind regards,
Hugo