sonic surrounds

via the Pd-list comes an opportunity to play with 36 loudspeakers:

Weekend of Speakers Call

13th June to 15 June

Call for fixed media, performance and improvisation work to be
diffused across 36 discrete loud speakers and explore the particular
physicality of the location (St Paul’s Hall).

Works are required for a variety of performance, improvisation and
installations settings: floorplan and speaker placement maps are on
the website (see below). While traditional tapes works are welcome,
laptop performance, live diffusion, installation and instrumental
works with electronics in particular are sought.

For more see online @ www.inclusiveimprov.co.uk/wofs

Were? St Paul’s Hall, University of Huddersfield, UK

When? June 13th -> June 15th

Cost? All Events Free -in fact this is all being done on favors

To submit work for consideration please email
calls@inclusiveimprov.co.uk by May 19th with appropriate links. And if
you have a really crazy idea for this opportunity email us with your thoughts.

filmachine is a multichannel spatial audio & visual installation by artists Keiichiro Shibuya and Takashi Ikegami currently installed at the Podewils’sches Palais (ex Tesla) in Berlin, for Transmediale 2008. The description on the transmediale website goes as follows:

filmachine places the visitor inside a vortex of sound and light that transcends the traditional perspective of the cinematic experience. Three circles of loudspeakers are suspended from the ceiling above an abstract landscape. On entering the space, the visitor starts the composition with a button at the center of the piece, triggering an immersive audio-visual experience in a 3-dimensional soundscape, enhanced by a specially designed LED lighting system. For the exhibition in Berlin, Keiichiro Shibuya creates a new composition which is presented here as a world premiere.

(more…)

Philippe-Aubert Gauthier has published a useful classification of spatial sound reproduction technologies, based on a large bibliography and some early feedback.

His top level categories of classification are the paradigm of sound field simulation, being either physics-based (eg wavefield synthesis), or perception-based (examples range from stereophony to synthesis of fundamental binaural cues).

The categorisation is nicely lateral in its thinking, for example, including exterior soundfield simulation that might be used to synthesis instrument directivity patterns (although this section neglects to mention O-Format, a method analogous to B-Format Ambisonics for representing outward facing directivity patterns using spherical harmonics). Another omitted technology is Vector Based Ampitude Panning (VBAP), for synthesising interior sound fields, though it might be hard to categorise into either physics-based or perception-based.

That said, this website offers a good introduction to a way of thinking about spatial sound reproduction that is more expansive than many information sources.

There seem to be many ambisonic microphones popping up around the place - both high-end and mid-range commercial microphones, as well as home-built DIY microphones.

Here are some photos and links.
(all images’ copyright owned by their respective manufacturers).

The premier ambisonic microphone range by Soundfield is soon to include a (presumably cheaper) A-Format microphone, the SPS200 (pdf link).

AGM Digital are redeveloping their MR1, originally developed with Danish Pro Audio using matched B&K 4011 capsules.

Core Sound are about to release their TetraMic a-format ambisonic microphone.

On the DIY side:
In 2005, I made my own DIY ambisonic microphone using Panasonic electret capsules, which turned out to be great quality for a cost of around $300.

Also in 2005, Etienne Deleflie built his Sound Thief ambisonic microphone using Rode NT5 microphone parts (capsule and phantom preamps).

Earlier, Henry J. Walmsley had already built his own ambisonic microphone also using Panasonic capsules.

In late 2006, I heard of two more new DIY ambisonic mics:
Rafael Kassier’s mic built from Oktava capsules:

and Paul Doornbusch’s beautifully constructed DIY mic built with Transound capsules:

Probably you could find out about more diy ambi mics by joining the Sursound list.

here’s a screenshot of the Pd interface that I developed to perform for Electrofringe 2006.

click on the image for full sized version:

I made heavy use of the (now quite usable) Graph on Parent feature - so that I could instantiate abstraction subpatches that created each of those GUI blocks in the patch.

Blocks aren’t really well labeled in this screenshot, but from left to right, top to bottom, these are the abstractions I developed and used in the patch:

• on the first row:
• a timer (clock), so i know how long i’ve been playing
• a “heartbeat” synth i made which emits a nice low bass pulse
• then three instances of the same ambisonic audio file player (that plays back my 4 channel ambisonic field recordings, and decodes them to 5 channel surround format)
• a single instance of a stereo audio file player
• on the second row:
• two instances of my 5 channel granulator - based on an improved version of the stereo granulator i’ve released elsewhere on my website
• a surround glitch/pop generator based on filtered single sample impulses with controlled stochastic triggering and panning
• and on the final row:
• a CPU load meter
• DSP switch
• mixer for all the abstractions, grouped into foreground and background sounds
• and the 5 channel output and recorder - which was the last thing i implemented, and seemed unreliable, so i didn’t use it to record my performance live. i’ll record a version sometime soon.