MULTICOMB

Multiple comb filters.

in RTcmix/insts/std

quick syntax:

MULTICOMB(outsk, insk, dur, AMP, combfreqlo (Hz), combfreqhi (Hz), REVERBTIME[, inputchan, ringdowndur])

CAPITALIZED parameters are pfield-enabled for table or dynamic control (see the maketable or makeconnection scorefile commands). Parameters after the [bracket] are optional and default to 0 unless otherwise noted.

Param Field Parameter Units Dynamic Optional Notes  
p0 output start time seconds no no    
p1 input start time seconds no no    
p2 input duration seconds no no    
p3 amplitude multiplier relative multiplier of input signal yes no    
p4 comb frequency range bottom Hz no no    
p5 comb frequency range top Hz no no    
p6 reverb time seconds yes no    
p7 input channel - no yes default: 0  
p8 ring-down duration seconds - no yes default: p6 value

Parameters labled as Dynamic can receive dynamic updates from a table or real-time control source.

Author: Brad Garton; rev. for v4.0 by JGG, 7/10/0

MULTICOMB process an input signal using four simultaneous comb filters randomly chosen within a specified range (and spread across the stereo field)

Usage Notes

You can’t specify the actual comb filter frequencies chosen directly, but it’s still fun to use. Narrow ranges will converge on a particular pitch if you’d like.

The optional ring-down duration parameter (p8) is to let you control how long the combs will ring after the input has stopped. If the reverb time is constant, MULTICOMB will figure out the correct ring-down duration for you. If the reverb time is dynamic, you need to specify a ring-down duration if you want to ensure that your sound will not be cut off prematurely.

The output of MULTICOMB is stereo.

Sample Scores

very basic:

   rtsetparams(44100, 2)
   load("MULTICOMB")

   rtinput("mysound.aif")

   ampenv =  maketable("line", 1000, 0,0, 0.5,1, 4.0,1, 4.3,0)

   MULTICOMB(0, 0, 4.3, 0.1*ampenv, cpspch(6.02), cpspch(9.05), 1)

slightly more advanced:

   set_option("full_duplex_on")
   rtsetparams(44100, 2, 256)
   load("MULTICOMB")

   rtinput("AUDIO")
   reset(20000)

   srand(87)

   ampenv = maketable("line", 1000, 0,0, 1,1, 3,1, 5,0)

   for(start = 0; start < 30; start = start + 2.5) {
      low = random() * 500.0 + 50.0
      hi = low + (random() * 300.0)
      MULTICOMB(start, 0, 5, 0.04, low, hi, 2.5)
   }

See Also

maketable, COMBIT, DELAY, FLANGE, IIR, JDELAY, REV, REVERBIT, REVERBIT