Stationary source roomsimulation.
in RTcmix/insts/std/MMOVE
MPLACE(outskip, inskip, dur, AMP, distxpos, angleypos, ()dist_mikes[, input_channel])
RVB(outskip, inskip, dur, AMP)
space(front, right, back, left, ceiling, absorb, rvbtime)
mikes(mike_angle, pattern)
mikes_off()
set_attenuation_params(min_dist, max_dist, dist_exponent)
matrix(amp, matrixval1, matrixval2, … matrixval144)
CAPITALIZED parameters are pfieldenabled 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.
MPLACE employs several subcommands to set the roomsimulation characteristics and one subinstrument (RVB) to operate.
For these commands, parameters labled as Dynamic can receive dynamic updates from a table or realtime control source.
MPLACE
Param Field  Parameter  Units  Dynamic  Optional  Notes 

p0  output start time  seconds  no  no  
p1  input start time  seconds  no  no  
p2  duration (or endtime if negative)  seconds  no  no  
p3  amplitude multiplier  relative multiplier of input signal  yes  no  
p4  distance to sound source  feet  no  no  polar 
OR xcoordinate of sound source  feet  no  no  cartesian  
p5  angle to sound source  degrees; 0 degrees is straight in front  no  no  polar 
OR ycoordinate of sound source  feet  no  no  cartesian  
p6  distance between ‘mics’ (stereo receivers) in the room  feet  no  no  if negative, cartesian coords, else polar 
p7  input channel    no  yes  default: 0 
RVB
Param Field  Parameter  Units  Dynamic  Optional  Notes 

p0  output start time  seconds  no  no  
p1  input start time  seconds  no  no  
p2  duration (or endtime if negative)  seconds  no  no  
p3  amplitude multiplier  relative multiplier of input signal  yes  no 
NOTE: this associated instrument is required for MPLACE to function
space
Param Field  Parameter  Units  Dynamic  Optional  Notes 

p0  distance to front wall of room  feet  no  no  
p1  distance to righthand wall of room  feet  no  no  
p2  distance to back wall of room  feet  no  no  specified as negative 
p3  distance to lefthand wall of room  feet  no  no  specified as negative 
p4  distance to ceiling of room  feet  no  no  
p5  wall absorption factor  010  no  no  0 == more ‘dead’, 10 == more ‘live’ 
p6  reverberation time  seconds  no  no  0  ~5 work best 
NOTE: this subcommand is required for MPLACE to function
mikes
Param Field  Parameter  Units  Dynamic  Optional  Notes 

p0  microphone angle  degrees, 0 degrees is straight in front  no  no  
p1  microphone pattern  01; 0 == omnidirectional, 1 == highly directional  no  no 
NOTE: this subcommand is optional for MPLACE to function (the default is “mikes_off”)
mikes_off
No pfields. This turns off the microphone angle and pattern settings to allow binaural simulation.
NOTE: this subcommand is optional for MPLACE to function
set_attenuation_params
Param Field  Parameter  Units  Dynamic  Optional  Notes 

p0  minimum distance  feet  no  no  default: 0 
p1  maximum distance  feet  no  no  default: infinite 
p2  distance attentuation exponent    no  no  default: 2 
NOTE: this subcommand is optional for MPLACE to function
matrix
Param Field  Parameter  Units  Dynamic  Optional  Notes 

p0  total matrix gain  relative multiplier of input signal  no  no  
p1p145  12 x 12 matrix amp/feedback coefficients    no  yes  defaults to internal matrix 
NOTE: this subcommand is optional for MPLACE to function
MPLACE is an updated version of PLACE, Doug Scott’s room simulation RTcmix instrument. It places a sound in a room of your design and simulates the acoustic resonances of the room. Early reflections are computed using a raytracing approach based in the distances between the source, the listening ‘microphones’ and the walls. The generalized room reverberation is simulated using a 12 x 12 matrix of delay elements with feedback and filtering designed to imitate the global reverberation response of the specified room. This is done using the associated RVB instrument. Localization of the source sound is very good using MPLACE.
The room design for MPLACE depends on parameters specified in the setup subcommand. The parameters work by assuming that the listener (YOU) is placed at point [0,0] in a coordinate space. The locations of the four walls are specified in this x,y coordinate system (“front”, “right”, “back”, “left”):
y

x0x

y
Therefore the distance to the back and left walls must be specified as negative. All, including height, are in feet. “absorb” is a number between 0 (minimum) and 10 (maximum) that determines how reflective the walls are. “rvbtime” is the approximate length of reverb in seconds (the actual length depends on the size of the room).
MPLACE sets the location of the source sound by specifying the distance to the sound (“distxpos”) and the angle (“angle_ypos”) of the sound:
0.0 source
 /
 /
 /
 /
/
you
using feet and degrees, respectively (see below for an alternative method of specifying the source location). Be sure to stay inside bounds of the room (it may take a bit of trigonometry [or guessing] to do that) The “AMP” pfield is a multipler of the input audio prior to any processing by MPLACE. The “dist_mikes” parameter sets how far apart the two ‘listening’ points are from the [0,0] center of the coordinate room (you can choose to think of this is how big the listener’s head is…).
A call to MPLACE should be followed by a call to RVB to create the diffuse room reverberation. RVB should be configured using the bus_config aux bus system to received the audio output from MPLACE.
When specifying the parameters for MPLACE, be aware that the interpretation of the p4 and p5 pfields (“distxpos”, “angleypos”) depends on whether or not p6 (“dist_mikes”) is positive or negative. The distance to the mikes (p6) will be interpreted as a positive number in any case, but if it is entered as negative it will cause p4 and p5 to be interpreted as cartesian coordinates on a coordinate plane where the center of the listener is located at [0, 0]. The default interpretation is to use polar coordinates for the sound source information (distance to sound, angle to sound).
The optional subcommands that may be used to set the parameters for MPLACE include mikes and mikes_off. mikes is a setup call for times when you wish to simulate microphone recording (most of the time, actually). The arguments are “mike_angle”, which is the angle each microphone makes with a line drawn between them (i.e., 45 puts them at a 90 degree angle FROM EACH OTHER). “pattern” is a value between 0 and one; 0 produces an omnidirectional mike, 1 produces a hypercardioid pattern, 0.5 produces the familiar cardioid pattern. The default pattern will be omnidirectional.
mikes_off is used following a previous call to mikes in order to cancel mike mode in the event that you wish to use binaural mode, or default to omnidirectional.
set_attenuation_params can set certain values that may be important during processing. p0 sets a minimum distance for a sound in feet. If the sound approaches the mike or ear closer than this, its volume will not increase beyond the maximum level (unity gain). Default is 0.0.
p1 sets the maximum distance for a sound in feet. If the sound exceeds this distance, its volume is not attenuated beyond the level associated with the maximum distance. Default is infinite.
The attentation factor (p2) determines the amount sound will decay over the distance traveled. Sounds will attenuate according to the formula:
a = 1.0 / ((d/mindistance) ** (factor))
where d is the distance to the sound, and factor is the attenuation factor (2.0 is the default value). NOTE: In the current version, ALL sound path gains are affected by these values, including all first and secondgeneration reflections! Modifying these values will therefore produce significant and interesting changes in the reverb as well as the gain of the sounds.
matrix is used to replace the default set of amplitude/feedback coefficients for the RVB matrix – all 144 of them. This is tricky to use.
Note that multiple MPLACE notes can feed into a single RVB instrument for more efficient processing.
MPLACE/RVB requires stereo output.
basic use:
rtsetparams(44100,2,4096)
load("MPLACE")
bus_config("MPLACE", "in 0", "aux 01 out")
bus_config("RVB", "aux 01 in", "out 01")
rtinput("mysoundfile.wav")
mikes(45, 0.5)
dist_front = 100
dist_right = 130
dist_rear = 145
dist_left = 178
height = 100
rvbtime = 3
abs_fac = 8
space(dist_front, dist_right, dist_rear, dist_left, height, abs_fac, rvbtime)
insk = 0
outsk = 0
dur = DUR(0)
pre_amp = 120
dist2sound = 60
angle_sound = 90
dist_mikes = 5
//dist_mikes = 0.67 /* binaural */
inchan = 0
MPLACE(outsk, insk, dur, pre_amp, dist2sound, angle_sound+180, dist_mikes, inchan)
MPLACE(outsk+(256/44100), insk, dur, pre_amp, dist2sound, angle_sound, dist_mikes, inchan)
MPLACE(outsk+0.5, insk, dur, pre_amp,dist2sound*1.3, angle_sound+270, dist_mikes, inchan)
RVB(0, 0, dur+rvbtime+0.5, 1)
DMOVE, FREEVERB, GVERB, MMOVE, MOVE, MROOM, PLACE, REV, REVERBIT, ROOM, SROOM