The probable reason is that the two halves of the tuning pot don't track closely enough and at some point the loop gain is too high.Hi @abbey road d enfer , sorry for insisting on this but what is the reason the SVF oscillates when forced to cover a full range spectrum (ie. 40Hz-15KHz). I thought it would be due to particular opamp limitations they 'run out of juice', but I tried with other opamps with very high output specs and bandwidth and same happens. Could you please share with me what the limiting factor is?
Does the circuit oscillate whatever the position of the tuning pot?
40-15k is a ratio of 300+. SVF's filters have a typical range of 1:30, which often uses switching for covering the audio spectrum in two ranges.