Hi.
While experimenting with an op-amp integrator stage and an all-pass filter stage, I obtained serendepitously a shelving filter, that can be either configured as low or high shelf. The side effects of the design however is that it exhibits resonance (a more complex transition band, with notch effect at f1 and resonance at f2). Obviously this means more pronouced phase effects, and it also has interdepence in the pot controls, as one pot may affect multiple characteristics at once.
I was wondering if resonance would be primarily seen as an unwanted side effect for such filters or could it have some applications ?
There are digital implementations of such filters - robert bristow-johnson's Audio EQ Cookbook1 so it may have been explored.
I have not done a transfer function characterisation yet, I mainly explored the features empirically. I may do it in the future if I find time or if it is worth it.
Also, Do you know any other analog implementation that exhibits resonance so I can compare the designs ?
I've put the ASC file there : Audio shelving filter with resonance. - SKYNEXT Tech.
Have a nice day !
While experimenting with an op-amp integrator stage and an all-pass filter stage, I obtained serendepitously a shelving filter, that can be either configured as low or high shelf. The side effects of the design however is that it exhibits resonance (a more complex transition band, with notch effect at f1 and resonance at f2). Obviously this means more pronouced phase effects, and it also has interdepence in the pot controls, as one pot may affect multiple characteristics at once.
I was wondering if resonance would be primarily seen as an unwanted side effect for such filters or could it have some applications ?
There are digital implementations of such filters - robert bristow-johnson's Audio EQ Cookbook1 so it may have been explored.
I have not done a transfer function characterisation yet, I mainly explored the features empirically. I may do it in the future if I find time or if it is worth it.
Also, Do you know any other analog implementation that exhibits resonance so I can compare the designs ?
I've put the ASC file there : Audio shelving filter with resonance. - SKYNEXT Tech.
Have a nice day !
