interpretor/faust-0.9.47mr3/examples/faust-stk/uniBar.dsp

   1 declare name "UniBar";
   2 declare description "Nonlinear Banded Waveguide Models";
   3 declare author "Romain Michon";
   4 declare copyright "Romain Michon (rmichon@ccrma.stanford.edu)";
   5 declare version "1.0";
   6 declare licence "STK-4.3"; // Synthesis Tool Kit 4.3 (MIT style license);
   7 declare description "This instrument uses banded waveguide. For more information, see Essl, G. and Cook, P. Banded Waveguides: Towards Physical Modelling of Bar Percussion Instruments, Proceedings of the 1999 International Computer Music Conference.";
   8
   9 import("music.lib");
  10 import("instrument.lib");
  11
  12 //==================== GUI SPECIFICATION ================
  13
  14 freq = nentry("h:Basic_Parameters/freq [1][unit:Hz] [tooltip:Tone frequency]",440,20,20000,1);
  15 gain = nentry("h:Basic_Parameters/gain [1][tooltip:Gain (value between 0 and 1)]",0.8,0,1,0.01);
  16 gate = button("h:Basic_Parameters/gate [1][tooltip:noteOn = 1, noteOff = 0]");
  17
  18 select = nentry("h:Physical_and_Nonlinearity/v:Physical_Parameters/Excitation_Selector
  19 [2][tooltip:0=Bow; 1=Strike]",0,0,1,1);
  20 integrationConstant = hslider("h:Physical_and_Nonlinearity/v:Physical_Parameters/Integration_Constant
  21 [2][tooltip:A value between 0 and 1]",0,0,1,0.01);
  22 baseGain = hslider("h:Physical_and_Nonlinearity/v:Physical_Parameters/Base_Gain
  23 [2][tooltip:A value between 0 and 1]",1,0,1,0.01);
  24 bowPressure = hslider("h:Physical_and_Nonlinearity/v:Physical_Parameters/Bow_Pressure
  25 [2][tooltip:Bow pressure on the instrument (Value between 0 and 1)]",0.2,0,1,0.01);
  26 bowPosition = hslider("h:Physical_and_Nonlinearity/v:Physical_Parameters/Bow_Position
  27 [2][tooltip:Bow position on the instrument (Value between 0 and 1)]",0,0,1,0.01);
  28
  29 //==================== MODAL PARAMETERS ================
  30
  31 preset = 1;
  32
  33 nMode(1) = 4;
  34
  35 modes(1,0) = 1;
  36 basegains(1,0) = pow(0.9,1);
  37 excitation(1,0) = 1*gain/nMode(1);
  38
  39 modes(1,1) = 2.756;
  40 basegains(1,1) = pow(0.9,2);
  41 excitation(1,1) = 1*gain/nMode(1);
  42
  43 modes(1,2) = 5.404;
  44 basegains(1,2) = pow(0.9,3);
  45 excitation(1,2) = 1*gain/nMode(1);
  46
  47 modes(1,3) = 8.933;
  48 basegains(1,3) = pow(0.9,4);
  49 excitation(1,3) = 1*gain/nMode(1);
  50
  51 //==================== SIGNAL PROCESSING ================
  52
  53 //----------------------- Synthesis parameters computing and functions declaration ----------------------------
  54
  55 //the number of modes depends on the preset being used
  56 nModes = nMode(preset);
  57
  58 //bow table parameters
  59 tableOffset = 0;
  60 tableSlope = 10 - (9*bowPressure);
  61
  62 delayLengthBase = SR/freq;
  63
  64 //delay lengths in number of samples
  65 delayLength(x) = delayLengthBase/modes(preset,x);
  66
  67 //delay lines
  68 delayLine(x) = delay(4096,delayLength(x));
  69
  70 //Filter bank: bandpass filters (declared in instrument.lib)
  71 radius = 1 - PI*32/SR;
  72 bandPassFilter(x) = bandPass(freq*modes(preset,x),radius);
  73
  74 //Delay lines feedback for bow table lookup control
  75 baseGainApp = 0.8999999999999999 + (0.1*baseGain);
  76 velocityInputApp = integrationConstant;
  77 velocityInput = velocityInputApp + _*baseGainApp,par(i,(nModes-1),(_*baseGainApp)) :> +;
  78
  79 //Bow velocity is controled by an ADSR envelope
  80 maxVelocity = 0.03 + 0.1*gain;
  81 bowVelocity = maxVelocity*adsr(0.02,0.005,90,0.01,gate);
  82
  83 //stereoizer is declared in instrument.lib and implement a stereo spacialisation in function of
  84 //the frequency period in number of samples
  85 stereo = stereoizer(delayLengthBase);
  86
  87 //----------------------- Algorithm implementation ----------------------------
  88
  89 //Bow table lookup (bow is decalred in instrument.lib)
  90 bowing = bowVelocity - velocityInput <: *(bow(tableOffset,tableSlope)) : /(nModes);
  91
  92 //One resonance
  93 resonance(x) = + : + (excitation(preset,x)*select) : delayLine(x) : *(basegains(preset,x)) : bandPassFilter(x);
  94
  95 process =
  96                 //Bowed Excitation
  97                 (bowing*((select-1)*-1) <:
  98                 //nModes resonances with nModes feedbacks for bow table look-up
  99                 par(i,nModes,(resonance(i)~_)))~par(i,nModes,_) :> + :
 100                 //Signal Scaling and stereo
 101                 *(14) : stereo : instrReverb;