SROOM

PLACE does a better job of room-simulation, although it is more computationally expensive.

Here's more description from older documentation of the disk-based cmix "sroom" instrument (also see the documentation for MROOM:

These room simulation routines will add reverberation and "roominess" to BSD-type soundfiles (integer or floating point) that are processed through them. delay lines from the source to the listener. The room model is rectangular, delay paths are based on "ideal" reflections from the walls, the `listener' has an exandable head, and reverberation is added to the delay lines to simulate diffusion from reflections of reflections. MROOM will create the same room model that SROOM will and pass a moving source through it.

SROOM will calculate the delay paths from the walls of a rectangular room to two points representing the corners of an "inner" or listening room. The room is set up on a Cartesian coordinate system (x-y plane) with the center of the inner room's front wall positioned at the origin (0,0).

The arguments 'insk', 'outsk', 'dur' and 'amp' represent the time to skip on the input file before beginning processing, the time to skip on the output file before writing the processed output, the duration of the input file to process, and an amplitude multiplier that will be applied to the input signal.

The variable 'Xroom' is the position along the x-axis where the right-hand wall should appear. SROOM will then create the left-hand wall at -xroom, so this value represents 1/2 the room's width (in feet). 'Yroom' is the position along the y-axis where the front wall will be drawn. The rear wall will be positioned at -yroom. 'Yroom' represents 1/2 the rooms height (also in feet).

The variables 'xsrc' and 'ysrc' are the x and y coordinates of the sound source. 'Rvbtime' is the amount of time (in seconds) it takes for the reverb comb filters to decay to .001 of their original value. Values greater than 1.0 - 1.5 tend to sound "metallic"; the frequency response of the reverb combs becomes clearly audible. '%rflct' is the percentage of sound reflected by the walls. A '%rflct' value of 100 will mean that the walls will not absorb any of the incident sound. The only attenuation in the delay paths will be due to the distance travelled from the source to the listener (-6 db for each doubling of distance). 'Xinner' is the width of the inner (or listening) room. The value represents 1/2 the true width of the inner room (in feet). 'Chan' is an optional argument to specify which channel of the currently opened input file to process through the room. The default is channel 0. Note that only one channel at a time may be processed through these rooms.

SROOM can use setline to draw an amplitude modification curve while mixing. If no call to setline is made there is no modification done. The syntax for the call is identical to that used in MIX

/* SROOM - room simulation with stationary sound source
      p0     output start time
      p1     input start time
      p2     input duration
      p3     amplitude multiplier
      p4     distance from middle of room to right wall (i.e., 1/2 of width)
      p5     distance from middle of room to front wall (i.e., 1/2 of depth)
      p6,p7  x,y position of source  (middle of room is 0,0)
      p8     reverb time (in seconds)
      p9     reflectivity (0 - 100; the higher, the more reflective)
      p10    "inner room" width (try 8)
      p11    input channel number   [optional]
*/

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

rtinput("/tmp/1stmove.snd")

outskip = 0
inskip = 13
dur = 9
amp = 0.8
xdim = 20
ydim = 20
xsrc = 10
ysrc = 10
rvbtime = 1.0
reflect = 90.0
innerwidth = 4.0
inchan = 0

SROOM(outskip, inskip, dur, amp,
      xdim, ydim, xsrc, ysrc, rvbtime, reflect, innerwidth, inchan)

outskip = 12
amp = 0.7
ydim = 50
xsrc = -30
reflect = 80.0

SROOM(outskip, inskip, dur, amp,
      xdim, ydim, xsrc, ysrc, rvbtime, reflect, innerwidth, inchan)