Hello,

I'm planning to do a graphic equalizer as fast convolution FIR filter in Pd. Let's say the equalizer has 10 sliders, one per octave. The question is how to translate the octave amplitudes to a smooth frequency curve. I was thinking about something along these lines:

1. upsample an array containing the amplitudes via FFT and larger zeropadded IFFT to get a smooth curve of 1024 points

2. warp the linear curve to logarithmic using [tabwrite4~] interpolation, to get 1024 spectrum points

Not sure if step 1 will work. Before reinventing the wheel, I'd like to know if someone has already built a graphic EQ FIR filter in Pd.

Katja