building an equalizer to filter a specific frequency

    May 01 2009 | 6:06 pm
    I am trying to build an equalizer to filter the frequency of an adc. At the moment, in my patch, i have the adc that sends a bang (when the sound hits a specific float) to my photo sequencer, that displays photos by an incoming sound from the adc. I basically need to filter a specific sound, so that it will change the photos, as it does now. I have tried to find an equalizer, but i didnt have any luck. Also tried to play around with the filtergraph, but i cant make it work.
    Any suggestions?
    i would appreciate it.
    check out the patch, its attached.

    • May 03 2009 | 7:43 pm
      hi - nice idea, & your patch basically works, but it's difficult to understand what you actually want to do from this description.
      for a start, you're using filtergraph wrong. it's not a filter object itself, it can't take a signal as an input. you need to put it through biquad~ - filtergraph is a controller for biquad~. check out the help file.
      are you trying to only let through a certain frequency band, (e.g. the bass) then measure the amplitudes of that to trigger photos?
    • May 03 2009 | 8:25 pm
      Cool, thank you for the suggestions!
      Well, i basically want to control the float object that is connected to the meter. I want to equalize this float. So in the beginning i have this float, which is basically representing the input to the adc and then have this number go through the filtergraph then out a new float. I need to filter a specific sound, and for that i need to know the exact number... yeah, i am basically a great deal of doubt of what to do.
    • May 03 2009 | 8:26 pm
      >>>>are you trying to only let through a certain frequency band, >>>>(e.g. the bass) then measure the amplitudes of that to trigger >>>>photos?
      actually yes!! sorry was too fast to reply there for a sec... any thoughts on how i could implement this?
    • May 04 2009 | 4:46 am
      ... well, the answer's in the question! once you've got filtergraph~ and biquad~ working (take a look at the help file, copy and paste it all if necessary) you can filter your signal so it's just the bass. then you take your meter (that you're getting your float from) and connect it to the filtered signal, rather than the unfiltered adc~. thus you're measuring the amplitudes of just the bass.
      from your first comment - you can't put a number through a filtergraph~. the number you're getting isn't a sound. you can't equalize a number. the number isn't "representing" the sound in a way that makes that possible. the number (float) you're getting is a periodical reading of the peak amplitude of the sound. you can't filter that!