I am quite new in filtering at all, so my questions are probably stupid. I have two issues with Juce
dsp::IIR::Filter that I can’t find the solution. So I would like to ask for help.
LOW PASS FILTER SLOPE
My first issue is about low pass filter slope. By slope I mean 6 dB per octave or 12 dB per octave etc.
I use code like that:
And later in the code I call:
myFilter.coefficients = dsp::IIR::Coefficients<float>::makeLowPass(sampleRate, freq, paramQ);
But as you can see there is no slope parameter. So is there any way to achieve Low Pass Filter with 6db per octave or any other slopes?
MAX FREQUENCY OF LOW PASS FILTER
My second issue is about highest frequency of filter. In
dsp::IIR::Coefficients::makeLowPass there is
jassert that doesn’t allow me to set frequency that is higher than 0.5 * sample rate. And this is obvious for me due to Nyquist frequency. But in all plugins EQ which I know there are constant range of frequencies, no matter what sample rate I have chosen in my DAW. For example in Fabfilter Pro-Q3, the max frequency is 25kHz, while users often uses sample rate 44,1kHz or 48kHz which is still less than 2 * 25kHz. So how they solve situation if user set in DAW lower sample rate than 2*maxFilterFreq? Don’t you know how to solve that with Juce dsp::IIR::Filter?
For any help great thanks in advance.