I've been trying to create a bandpass filter using the biquad~ object, and so far set it up as in the attached file. It's setup using following logic:
G, w0 and deltaw are adjustable, as the project shows.

As it is now, when I insert a sound file I'm able to change a bit on the sliders, but the sound completely disappear on certain settings, doesn't change in an expected manner, and the range of gain in which sound can be heard changes dependant on the other sliders(I should be able to simply adjust the filter's gain between -10 and 10 dB). I've gone through the math several times, and can't seem to find any errors, at least not if pd works the way I expect it to. Maybe there's an element that went over my head?

Any suggestions regarding this are highly appreciated, it's driving me nuts!

And a quick disclaimer: If you've seen a couple of posts similar to this one, they are other questions centered around the same project. I like to keep questions separate, even if they're for the same project.