Staalhemel » work-in-progress

visualisation: alpha and absence of alpha waves

Christoph De Boeck — Tue, 30 Nov 2010 11:21:23 +0000

This is what the plotting of data for alpha waves looked like in version 1 of the Max/MSP interface for the Staalhemel project.

data plotting for a running average of alpha waves

In the event windows on the left you see 3 windows with graphs colored (mainly) in red. The top window doesn’t show much information here; peaks will appear if there is synchronization in maximum values for alpha waves between both hemispheres. The middle window shows peaks of alpha waves over time. Color switches between red and black for each new visitor. The bottom graph reports the absence of alpha waves, which functions as an indicator of beta waves. The first version of the IMEC software did not deliver beta waves, but indicated if there was an absolute absence of alpha. This allowed me to infer moments of concentration (and the appearance of beta waves).

On the ‘frequency’ matrix display in the main window you see which steel segments are activated. This matrix represents the whole Staalhemel installation with a video window of 6 by 12 pixels (segments): the darker pixels indicate longer intervals between impacts for a particular plate. If they are white they are hammering at maximum speed (interval of 40 ms) and if they’re black they are off. The screenshot here shows a moment of concentration and the immediate response in activation of steel segments. You can see that just before this moment there was a sustained period of concentration, only interrupted by rather small amounts of alpha waves. This happened when I was working on the software while wearing the EEG headset and it tells how I was (minimally) distracted 4 times in that thinking process.

At STRP Festival in Eindhoven this version was installed for the last time.
The first day of the festival I did a testrun of the new software, Staalhemel version 2. In this update alpha and beta wave information for 8 channels is visualised. Due to certain limits and interferences this 8-channel version is not fully operational yet. This version maps the layout of your head to the installation matrix: front panel rows represent left and right frontal area of your brain, next rows show results from the side electrodes and top and back of the head are translated to the last rows of steel plates.

Staalhemel audio

Christoph De Boeck — Tue, 20 Apr 2010 09:59:37 +0000

Below you find the first sample that was made available of Staalhemel as a percussive machine. The concert version took place on 24 April 2010 in Happy New Festival, Kortrijk, Belgium.

Impact – binaural mic by audiostore

musical interface

Christoph De Boeck — Sun, 28 Mar 2010 21:19:17 +0000

musical interface for Staalhemel

Preparing the musical interface in Max/MSP to control the Staalhemel installation as a percussive apparatus. On the opening of the Sound Art expo at Festival van Vlaanderen Kortrijk the premiere will take place of this concert version. In the concert version De Boeck will operate the 80 steel tiles manually via a touchscreen while his brainwaves will operate other musical parameters.

Concert: 24 april, Budascoop, Kortrijk (B) – 20:15

steel matrix

Christoph De Boeck — Tue, 15 Sep 2009 22:09:27 +0000

The visitor’s brainwave fluctuations produce a dynamical distribution of taps over the grid of steel objects. The steel matrix is suspended at 2m50, typical for ceiling height. It is important for visitors to walk below the steel sky and experience the acoustic shifts in direction. ‘Staalhemel’ was originally conceived as an immersive sound art project. When visitors watch the whole of the installation frontally as one total object and from a distance, they will only hear the sum total of acoustic reflections from 80 pins hitting on steel. This acoustic monolith is very diffuse, shapeless and relatively loud. When however the visitors pass below the matrix, sound sources become very defined as they hear the pins directly above their head changing their frequency. Visitors are enveloped by a dynamic acoustic cloud of which details change when they move position.

first set-up

Christoph De Boeck — Sat, 25 Jul 2009 16:32:31 +0000

Images from the first build-up at Arts Centre Netwerk in Aalst, Belgium.

project sketch

Christoph De Boeck — Wed, 27 May 2009 21:54:37 +0000

A visitor walks under a sky of steel segments.
Hammers are mounted on top of the steel – they respond to the brainwaves of the visitor.
Visitors receive a wireless EEG brain scanner one by one, while others can watch and listen.

steel surface

Christoph De Boeck — Mon, 25 May 2009 15:28:50 +0000

The segments suspended at a height of 2m50 are made of hot rolled steel sheets. The heating process leaves traces of discoloration on the surface. These colour gradations form patterns that mark the sky.

Contiguous segments derived from one single original sheet will be dislocated so as to accentuate the puzzle-like aspect of our consciousness.

All pieces have been cut to the uniform size of 700 x 700 x 2 mm. These dimensions deliver a rich musical spectrum when the plate is struck with a pin.