interpreter/preprocessor/faust-0.9.47mr3/examples/freeverb.dsp

   1 declare name            "freeverb";
   2 declare version         "1.0";
   3 declare author          "Grame";
   4 declare license         "BSD";
   5 declare copyright       "(c)GRAME 2006";
   6 declare reference       "https://ccrma.stanford.edu/~jos/pasp/Freeverb.html";
   7
   8 //======================================================
   9 //
  10 //                                              Freeverb
  11 //                Faster version using fixed delays (20% gain)
  12 //
  13 //======================================================
  14
  15
  16 // Constant Parameters
  17 //--------------------
  18
  19 fixedgain       = 0.015;
  20 scalewet        = 3.0;
  21 scaledry        = 2.0;
  22 scaledamp       = 0.4;
  23 scaleroom       = 0.28;
  24 offsetroom      = 0.7;
  25 initialroom     = 0.5;
  26 initialdamp     = 0.5;
  27 initialwet      = 1.0/scalewet;
  28 initialdry      = 0;
  29 initialwidth= 1.0;
  30 initialmode     = 0.0;
  31 freezemode      = 0.5;
  32 stereospread= 23;
  33 allpassfeed     = 0.5;
  34
  35
  36 // Filter Parametres
  37 //------------------
  38
  39 combtuningL1    = 1116;
  40 combtuningL2    = 1188;
  41 combtuningL3    = 1277;
  42 combtuningL4    = 1356;
  43 combtuningL5    = 1422;
  44 combtuningL6    = 1491;
  45 combtuningL7    = 1557;
  46 combtuningL8    = 1617;
  47
  48 allpasstuningL1 = 556;
  49 allpasstuningL2 = 441;
  50 allpasstuningL3 = 341;
  51 allpasstuningL4 = 225;
  52
  53
  54 // Control Sliders
  55 //--------------------
  56 // Damp : filtrage des aigus des echos (surtout actif pour des grandes valeurs de RoomSize)
  57 // RoomSize : taille de la piece
  58 // Dry : signal original
  59 // Wet : signal avec reverbration
  60
  61 dampSlider              = hslider("Damp",0.5, 0, 1, 0.025)*scaledamp;
  62 roomsizeSlider  = hslider("RoomSize", 0.8, 0, 1, 0.025)*scaleroom + offsetroom;
  63 wetSlider               = hslider("Wet", 0.8, 0, 1, 0.025);
  64 drySlider               = hslider("Dry", 0, 0, 1, 0.025);
  65 combfeed                = roomsizeSlider;
  66
  67
  68
  69
  70
  71 // Comb and Allpass filters
  72 //-------------------------
  73
  74 allpass(dt,fb) = (_,_ <: (*(fb),_:+:@(dt)), -) ~ _ : (!,_);
  75
  76 comb(dt, fb, damp) = (+:@(dt)) ~ (*(1-damp) : (+ ~ *(damp)) : *(fb));
  77
  78
  79 // Reverb components
  80 //------------------
  81
  82 monoReverb(fb1, fb2, damp, spread)
  83         = _ <:  comb(combtuningL1+spread, fb1, damp),
  84                         comb(combtuningL2+spread, fb1, damp),
  85                         comb(combtuningL3+spread, fb1, damp),
  86                         comb(combtuningL4+spread, fb1, damp),
  87                         comb(combtuningL5+spread, fb1, damp),
  88                         comb(combtuningL6+spread, fb1, damp),
  89                         comb(combtuningL7+spread, fb1, damp),
  90                         comb(combtuningL8+spread, fb1, damp)
  91                 +>
  92                         allpass (allpasstuningL1+spread, fb2)
  93                 :       allpass (allpasstuningL2+spread, fb2)
  94                 :       allpass (allpasstuningL3+spread, fb2)
  95                 :       allpass (allpasstuningL4+spread, fb2)
  96                 ;
  97
  98 stereoReverb(fb1, fb2, damp, spread)
  99         = + <:  monoReverb(fb1, fb2, damp, 0), monoReverb(fb1, fb2, damp, spread);
 100
 101
 102 // fxctrl : add an input gain and a wet-dry control to a stereo FX
 103 //----------------------------------------------------------------
 104
 105 fxctrl(g,w,Fx) =  _,_ <: (*(g),*(g) : Fx : *(w),*(w)), *(1-w), *(1-w) +> _,_;
 106
 107
 108
 109 // Freeverb
 110 //---------
 111
 112 freeverb = vgroup("Freeverb", fxctrl(fixedgain, wetSlider, stereoReverb(combfeed, allpassfeed, dampSlider, stereospread)));
 113
 114 process = freeverb;