audio sensor box


    Sep 21 2006 | 10:51 am
    hi there : ) i'm trying to use fiddle~ in order to obtain the audio signal coming from an audio sensor box in www.antfood.com can anyone give me a hint about a patch to do this? thank you

    • Sep 21 2006 | 12:29 pm
    • Sep 21 2006 | 1:29 pm
      I think the URL is here:
      The box sends out an audio signal ranging from 10khz to 20 khz, so Fiddle would be an appropriate object to use.
    • Sep 21 2006 | 1:56 pm
      On 21 Sep 2006, at 14:29, David Whitely wrote:
      > > I think the URL is here: > > http://www.antfood.com/ads/audiosensing.htm > > The box sends out an audio signal ranging from 10khz to 20 khz, so > Fiddle would be an appropriate object to use.
      Except that he is using fixed frequency oscillators, which are amplitude modulated by the data. fiddle~ is for frwequency tracking, which is not relelvant here. He suggests using fft; you might also try narrow band filters tuned to each of the frequencies.
      Best
      L
      Lawrence Casserley - lawrence@lcasserley.co.uk Lawrence Electronic Operations - www.lcasserley.co.uk Colourscape Music Festivals - www.colourscape.org.uk
    • Sep 21 2006 | 2:03 pm
      Maybe you can write to the creator of the antbox for an example max patch?
      dw
    • Sep 21 2006 | 2:27 pm
      thanks :) i wrote him but i got no answer...i'll keep on trying...
      2006/9/21, David Whitely : > > > Maybe you can write to the creator of the antbox for an example max patch? > > dw >
    • Sep 22 2006 | 4:39 pm
    • Sep 22 2006 | 6:37 pm
      Hello, Here is a patch that theoretically does something like what you will need to do. The rect~ objects are merely there as a model of the square waves that you will be receiving from your audio interface. The FFT portion passes only a specific frequency bin of amplitude data. From this, you can use abs~ and rampsmooth~ to follow the amplitude of the signal. Remember that you will most likely need to tune your oscillators so that they fit nicely into different frequency bins. Looking at the schematic, it appears that the left and right channel use the same oscillators.
      Seems like a pretty cool circuit. I may try building it myself just to see if it works as advertised.
      Cheers, Andrew B.
    • Sep 23 2006 | 11:12 am