Details - communication between the two concert halls
In order to communicate correctly during the preparation, the rehearsal and the performance of ius lucis, it is important to create adequate ways of visual and audio communications between the two places.
Audio intercom
In addition to a conventional audio intercom between the technical teams, we used a dedicated telephonic line between the sound regies.
network messaging
The computers are connected via an internet line. The computer music designers responsible of the transformations were communicating informations during the rehearsal via the iChat messaging software.
Video projection
For the musical synchronisation of the ensembles, the 6 musicians in room B should have a video image of the conductor located in room A. As they are separated from each other, each one of these musicians have a video monitor.
Details - Midi Devices
Midi Keyboard in ensemble A
All the electronic events of ius lucis are triggered by the Midi keyboard playing in ensemble A. It should have 88 keys and the possibility to send program changes. This keyboard is directly connected to the computer of room A. These informations are sent to the room B computer thru UDP vi the ethernet line (see patch UdpToEspro in main max patch).
Midi Mixers
To control the live balance of the transformation, two midi mixers (one in each room) are used. 8 faders controls the levels of the different "voices" of cross synthesis (see score)
1.Cross synthesis 1
2.Convolution 1
3.Cross synthesis 2
4.Convolution 2
5.Cross synthesis 3
6.Convolution 3
7.Spatialization 4 (and Ircam-Spatialisateur)
Ius lucis control panel subpatch
Ensemble A
in1 : oboe1
in2 : percussion
in3 : clarinette micro 1
in4 : clarinette micro 2
in5 : trio left (flute1, horn1, violin 1)
in6 : trio middle (contrabass clarinet, viola, cello)
in7 : trio right (flute2, horn2, violin 2)
There is 2 microphone for the Bb clarinet : one in front of it. and another one off axis by approx. 1 meter. This microphone is used for movement detection of the clarinettist in several sections of the work
The 3 trios are premixed.
Ensemble B
in1 : oboe2
in2 : clarinette micro 1
in3 : clarinette micro 2
in4 : trombone 1
in5 : tam 1
in6 : trombone 2
in7 : tam 2
in8 : viola 2
in9 : cello 2
There is 2 microphone for the Bb clarinet : on in front of it. an other one off axis by approx. 1 meter. This microphone is used for movement detection of the clarinettist in several sections of the work
Special microphones to capture the tam resonances
Ius - sound inputs A
Ius - sound inputs B
Details - loudspeakers configuration
Orchestras amplification
The instruments should be amplifiied locally and in a natural way.
Diffusion of the electronic parts
The sound transformations generated by the computers are spatialized in the halls
For this purpose, independantly from the loudspeakers required for the amplification, the audio outputs from the computers are sent to a set of 12 speakers for room A and 8 speakers for room B. This speakers are located around and above the audiences. For the placement of the speaker, refer to the following pictures
Loudspeaker setup for Room A
Loudspeaker setup for room A
Loudspeaker setup for Room B
Loudspeaker setup for room B
Implantation CGP (A)
Implantation Espro (B)
Install - maxMsp software installation
copy the following folders on the hard disk of both Macintoshes :
ius-MaxPatches
ius-sounds
ius-java
Launch MaxMsp
Set the Max File Preferences to point to the following folders
ius-MaxPatches/lib
ius-sounds
ius-java
In Max DSP Status, set the I/O Vector Size to 1024, the signal vector size to 512, and overdrive mode is off
Max status
Patch presentation - ius lucis main max patch
There is only one patch for both rooms. We have decided to use exactly the same program on each computer.
This patch (the version used for the premiere was iusLucisConcert126v) has to different configurations. The right configuration can be selected using the menu at the top of the main window
"CGP", meaning "Grande Salle of the Georges Pompidou Center" corresponds to room A
"Espro", meaning "Ircam 's Espace de Projection" corresponds to room B
Ius lucis main patch
Initialization - software initialization check list
On the Mac G5, launch MaxMsp 4.6.3
Open the iusLucisConcert126v patch
Depending on the room in which you are located, select the "CGP" or "Espro" mode
To initialize everything, select the "INIT 0" item on the event menu located at the left of the main main window.
Then select "TEST O" in the same menu.
Turn the DSP on
Ready to go !
Ius main max patch
Patch presentation - ius lucis patch contents
The following picture shows a synoptic view of the signal routing and treatments performed by the computer
Synoptic of ius lucis maxMsp patches
Patch presentation - Spatialisation techniques
Ircam "spatialisateur"
spatialisation vocabulary
Clarinets gesture audio captation
Estimation of the correlation of the sound signals received by two microphones located in front of the musicians
Spatialisation demo patch
Spatius help patch
Patch presentation - rooms resonance modes
To calculate the resonance modes of the rooms, we have used an applet by Paul Falstad
This java applet was ported to a max extern in C called modebox.mxo
Modebox patch
Mode exemple1
Modes exemple 2
Patch presentation - Real Time cross synthesis and convolution
Real Time cross synthesis and convolution
We developped a cross synthesis module in max msp. This module performs a real-time generalized cross synthesis close to the treatment provided by audiosculpt using the pfft~ object.
This module also perform a convolution on the two audio sources. The output of this convolution is then sent to a spectral mapping treatment conntrolled by the "spectral mapping mix" parameter.
It is possible to experiment with this module by opening the 2.ius.cross.demo that can be found in the SpectralTreatments folder.