Resonant filters ?

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Arnar
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Resonant filters ?

Are there any good or has anyone made a nice resonant filter in Designer ?
So far I have only found the VariableQ one , but it does not sound very nice , the others have very minimal resonance.

Steve I.
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Hi Arnar,

The Second Order Filter Control using the VariableQ filter type is indeed one of the main building blocks for Resonant filters. Not that since this is a second order filter, the transition band slope is 12 dB/octave, so it's not a sharp filter.  You can also introduce more/ different resonances with the PeakEQ and ShelfHighQ and ShelfLowQ filter types. You can cascade these modules and adjust their Q values either together or individually to tweak the sound. 

I attached an example that cascades a couple of filters with ganged controls. Let me know if you have any other ideas.

Steve

Binary Datacascaderesonant.awd

Arnar
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Nice thanks , this makes sense for a 24db Filter . I just don't like the way it sound very much but i will experiment :)
 Question : Why does the SOF Control in my toolbox only have two input pins and the one in the example has 2 control and one input , total 3?

Sidenote: It would make sense if control pins were a different color then the audio data pins , at least in my very limited experience.

Arnar
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What would be a good way to deal with the clipping caused by high Q values?
I used a soft clip module on the output , bit better but still a problem.
Maybe  limiter would be better?
Not sure how it works in AWD , would one filter clip into the other? , if working on a plugin it would not clip until it reaches the output.

Are there any recommended practices to avoid clipping in general ?

Arnar
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Also, would it be possible to make it behave-route like "analog" in that , could I feed the output signal inverted into the input of the filter and make "manual" resonance ? I would just try it but cannot see a way to route more then on pin into the input.

Arnar
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So far i can make it sound "resonant" but i can not make it self oscillate.
I am experimenting with trying to achieve a Synth style filter.
2x 12 db is getting somewhere , one of them in hpf , other lpf gets a half decent bandpass :)
But still cannot get that self oscillating synth style filter. 

Also a bit strange how the DC source max value does not seem to correspond to a freq ?
I can set it to hipass and at about 2k it sounds like its at almost 9k10 k.

Steve I.
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If you right click the filter module and choose the View Properties item on the context menu. Under the Arguments tab,  you will see that you can turn on control pins for frequency, Q, and gain.

You can avoid clipping by reducing the gain, either with the control pin or a scaler on the input -- High Q filters will add a bunch of gain around the cutoff frequency and may cause clipping. 

Good idea about the color differences on control pins. 

I'm open to hearing ideas about what would make this sound better. 

Steve I.
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Now I see what you are trying to achieve. I'll think about this.

Arnar
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Yes, reducing gain is possible .

As for getting it to sound better , not exactly sure , it just sounds very "digital" , hehe.
For my preferences I would want a filter that has synth characteristics , capable of self oscillation.
Possibly to be able to cascade multiple 6db filters and mess a bit with the inbetween stages.
Or being able to manually route feedback into the filter , and even introduce soft clipping or limiting in the feedback path?

Let me think about this a bit as I mess with this.

Steve I.
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Something else to play around with. You can try a Biquad module and set the coefficients using a formula. I've attached an example frequency response and an awd

Binary Datasecondorderresonator.awd

Arnar
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Thanks, will try this out!