History

IRCAM Spatialisateur

Summary

  • Description: The Spatialisateur project started in 1991 as a collaboration between Espaces Nouveaux and Ircam. Its goal is to propose a virtual acoustics processor which allows composers, performers or sound engineers to control the diffusion of sounds in a real or virtual space. This project stems from research carried out within the Ircam room acoustics laboratory on the objective and perceptive characterization of room acoustic quality. It also incorporates research done at Télécom Paris on digital signal processing algorithms for the spatialization and artificial reverberation of sounds. Spat~ is an effort to organize and optimize the experimental patches developped in the Spatialisateur project, in order to make them accessible to musicians and researchers who work with Max/MSP. The current release allows reproduction on multi-channel loudspeaker systems in studios or concert halls. It also integrates 3D stereo reproduction modes for headphones (binaural) or 2 loudspeakers (transaural), as well as Vector Based Amplitude Panning and Ambisonics.
  • Manufacturer / Developer: Ircam / Espaces Nouveaux
  • Version: 4.1.5
  • Platform: Spat 4 runs on Max/MSP version 5.0.0 or higher.
  • OS: Spat 4 is compatible with both Mac OS X (Universal Binary) and Windows XP/Vista.
  • License: The use of Spatialisateur and its documentation is restricted to members of the Ircam software users group.
  • Trademark: Spatialisateur is an IRCAM registered trademarks.
  • Patents: The design of Spat and the reverberation module are protected under different French and international patents ([FR] 92 02528; [US] 5,491,754, [FR] 95 10111; [US] 5,812,674).
  • Status of this entry: In progress

Parameter definition

Coordinate system convention

Spat 4 implements several coordinate systems, all defined from the listener’s point of view (i.e. the listener is the origin of the coordinate system). In Max/MSP these different coordinate systems are :

  • xyz : 3D Cartesian coordinates
  • xy : 2D Cartesian coordinate within xy plane
  • ade : azimuth, distance, elevation
  • aed : azimuth, elevation, distance
  • ad : azimuth, distance (2D within xy plane)
  • az : azimuth only (distance = 1 m)
  • spat3 : azimuth, distance, elevation format for backward compatibility with Spat 3.x convention

Spat 4 external objects can interpret messages formatted in any of these coordinate formats. Furthermore utilities objects are provided to perform conversions between the different coordinate systems.

Cartesian coordinates (xyz)

X axis on the right of the listener Y axis in front Z axis to the top


Top view (xy plane)


Front view (xz plane)

The default coordinate system in Spat 4 is called the navigational coordinate system. Positions are expressed in term of azimuth, elevation and distance (format “ade” in Max/MSP). Azimuth is measured toward the y axis, with 0° in front of the listener.
Elevation is 0° within xy plane. +90° on top, -90° bottom.


Navigational coordinates: Azimuth convention


Navigational coordinates: Elevation convention

Spat 3.x coordinate system (spat3)


Spat 3.x coordinate system for backwards compatibility

Parameters configuring the system

parameter description data format range initial state unit example misc
numsources number of sources int 1-64 1 N/A @numsources 5 Declared as an attribute to the external spat.spat~. This attribute can not be dynamically reconfigured.
numspeakers number of speakers int 0-128 1 N/A @numspeakers 8 Declared as an attribute to the external spat.spat~. This attribute can not be dynamically reconfigured.
numreverbs number of shared reverbs int 1-64 1 N/A @numreverbs 8 Declared as an attribute to the external spat.spat~. This attribute can not be dynamically reconfigured.
numinternals number of internal feedback channels int 1-64 1 N/A @numinternals 8 Declared as an attribute to the external spat.spat~. This attribute can not be dynamically reconfigured.
numcascades number of cascaded filters for output equalization int 1-8 1 N/A @numcascades 5 Declared as an attribute to the external spat.spat~. This attribute can not be dynamically reconfigured.
panning panning type (panr, bformat, vbap, vbap2d, xy, ms, ab, surround, angular, dbap, binaural, hoa symbol N/A angular N/A @panning vbap Declared as an attribute to the external spat.spat~. This attribute can not be dynamically reconfigured.
directsoundrerouting enable/disable direct sound rerouting (for wfs) int 0 .. 1 0
stereo stereo source as input int 0 .. 1 0

Parameter describing a sound source

parameter description data format range initial state unit example misc
pres source presence [list of float] list 0 .. 120 90
warmth source warmth [list of float] list 0 .. 60 30
bril source brillance [list of float] list 0 .. 60 30
prer room presence [list of float] list 0 .. 120 48
revp running reverberance [list of float] list 0 .. 50 34
env envelopment [list of float] list 0 .. 50 25
pitch source pitch [list of float] list -90 .. 90 0
sourcemute mute/unmute sources [list of int] list 0 .. 1 0
sourcesolo enable/disable solo mode [list of int] list 0 .. 1 0
sourceairabsorption enable/disable air absorption filtering [list of int] list 0 .. 1 1
doppler enable/disable doppler effect [list of int] list 0 .. 1 1
omni source omni filter parameters [list of float] list
axis source axis filter paramaters [list of float] list
reverbid index of reverb associated with source [list of int] list
drop drop factor [list of float] list -10 .. 30 6
dropmode drop mode [list of int] (0: log drop; 1:linear drop) list 0 .. 1 0
pan_rev pan/rev factor [list of float] list 0 .. 1 0
sourceinputgain source input gain [list of float] list -30 .. 10 0
sourceoutputgain source output gain [list of float] list -30 .. 10 0
source [index] [coordinates format] [list of coordinates] sets source positions anything
source [index] color [symbol] "sets source color (green, blue, red, yellow) " anything
source [index] name [symbol] sets source name anything
source [index] yaw [float] sets source yaw anything
source [index] aperture [float] sets source aperture anything
source [index] radius [float] sets source radius anything
source [index] pres [float] sets source presence anything
source [index] warmth [float] sets source warmth anything
source [index] bril [float] sets source brillance anything
source [index] prer [float] sets source room presence anything
source [index] revp [float] sets source running reverberance anything
source [index] env [float] sets source envelopment anything
source [index] pitch [float] sets source pitch anything
source [index] drop [float] sets source drop factor anything
source [index] dropmode [int] sets source drop mode (0: log drop; 1:linear drop) anything
source [index] pan_rev [float] sets source pan/rev factor anything
source [index] air [int] enable/disable air absorption filtering anything
source [index] doppler [int] enable/disable doppler effect anything
source [index] mute [int] mute/unmute sources anything
source [index] reverb [int] sets index of reverb associated with source anything
source [index] azim [float] sets azimuth and keep current elevation and distance unchanged
source [index] elev [float] sets elevation and keep current azimuth and distance unchanged
source [index] dist [float] sets distance and keep current azimuth and elevation unchanged
source [index] az [float] sets azimuth but use default elevation (0 deg) and distance (1m)
source [index] ae [float][float] sets azimuth and elevation but use default distance (1m)
source [index] ad [float][float] sets azimuth and distance but use default elevation (0 deg)
source [index] xy [float][float] sets x,y but use default z (0)
source [index] azim++ [float] increments azimuth and keep current elevation and distance unchanged
source [index] elev++ [float] increments elevation and keep current azimuth and distance unchanged
source [index] dist++ [float] increments distance and keep current elevation and azimuth unchanged
source [index] x++ [float] increments x and keep y and z unchanged
source [index] y++ [float] increments y and keep x and z unchanged
source [index] z++ [float] increments z and keep x and y unchanged

Parameter describing a virtual space

parameter description data format range initial state unit example misc
reverberance room reverberance [list of float] list 0 .. 100 65
heaviness room heaviness [list of float] list 0 .. 50 25
liveness room liveness [list of float] list 0 .. 50 35
early_start early start time [list of float] list 1 .. 120 20
early_end early end time [list of float] list 1 .. 120 40
early_distr early distribution centroid [list of float] list 0.1 .. 0.9 0.5
early_shape early shape factor [list of float] list 0 .. 1 0.5
early_width early width [list of float] list 10 .. 180 30
cluster_start cluster start time [list of float] list 1 .. 300 40
cluster_end cluster end time [list of float] list 1 .. 300 100
cluster_distr cluster distribution centroid [list of float] list 0.1 .. 0.9 0.5
reverb_start reverb start time [list of float] list 1 .. 500 95
modaldensity reverb modal density [list of float] list 0.2 .. 2 0.9
roomactive enable/disable reverb [list of int] list 0 .. 1 1
roomairabsorption enable/disable air absorption in reverb [list of int] list 0 .. 1 1
infinite enable/disable infinite reverb list 0 .. 1 0
roomairrolloff air absorption filtering roll off frequency [list of float] list 20 .. 20000 10000
roominputgain reverb input gain [list of float] list -30 .. 10 0
roomoutputgain reverb output gain [list of float] list -30 .. 10 0
room [index] reverberance [float] sets room reverberance anything
room [index] heaviness [float] sets room heaviness anything
room [index] liveness [float] sets room liveness anything
room [index] air [int] enable/disable air absorption filtering anything
room [index] active [int] enable/disable reverb anything
room [index] early start [float] sets early start time anything
room [index] early end [float] sets early end time anything
room [index] early distr [float] sets early distribution anything
room [index] early shape [float] sets early shape factor anything
room [index] early width [float] sets early width anything
room [index] cluster start [float] sets cluster start time anything
room [index] cluster end [float] sets cluster end time anything
room [index] cluster distr [float] sets cluster distribution anything
room [index] reverb start [float] sets reverb start time anything
room [index] reverb modaldensity [float] sets reverb modal density anything

Parameter describing the position of loudspeakers

parameter description data format range initial state unit example misc
speakers [coordinates format] [list of speakers coordinates] sets speakers positions anything
speaker [index] [coordinates format] [list of speakers coordinates] sets speaker position anything
speaker [index] name [symbol] sets speaker name anything

Parameter describing the post-processing of loudspeaker signals

parameter description data format range initial state unit example misc
delays output channel delays for time alignment [list of float] list 0 .. 100 0
outputfiltersfreq output channel equalizer cutoff/center frequency [list of float] list 50 .. 20000 1000
outputfiltersQ output channel equalizer resonance factor [list of float] list 0.5 .. 25 1
outputfiltersgain output channel equalizer gain [list of float] list -30 .. 30 0
outputfilterstype output channel equalizer filter type [list of symbol] list null
channel [index] delay [float] sets output channel delay anything
channel [index] cascade [index] freq [float] sets output channel equalizer cutoff/center frequency anything
channel [index] cascade [index] Q [float] sets output channel equalizer resonance factor anything
channel [index] cascade [index] gain [float] sets output channel equalizer gain anything
channel [index] cascade [index] type [symbol] sets output channel equalizer type anything

Other parameter

parameter description data format range initial state unit example misc
version prints object version in Max window
info prints infos (when available) in Max Window
hrtffile binaural filter set smybol
transauralfile transaural filter set symbol
clear clears internal buffers and filters memories
read [symbol] loads binaural filters from file anything
readtrans [symbol] loads transaural filters from file anything

Projects, sound, and music

  • art or research projects utilizing this spatial renderer

References

  • Bibliography

External Links

Media

  • GUI screenshots
  • Example patches
  • things which might explain the listed content better
  • you can add files to a wiki page by clicking on "new file" at the bottom

spat.xyz.1.png - Cartecian coordinates: Top view (xy plane) (40.8 KB) Trond Lossius, 12/29/2009 07:43 am

spat.xyz.2.png - Cartecian coordinates: Front view (xz plane) (33.3 KB) Trond Lossius, 12/29/2009 07:43 am

spat.azimuth.png - Navigational coordinates: Azimuth convention (39.2 KB) Trond Lossius, 12/29/2009 08:06 am

spat.elevation.png - Navigational coordinates: Elevation convention (40.8 KB) Trond Lossius, 12/29/2009 08:06 am

spat.spat3-backwards-compatibility.png - Spat 3.x coordinate system for backwards compatibility (39.2 KB) Trond Lossius, 12/29/2009 08:06 am

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