Archivi tag: resonance

Transforming a wooden floor into a multichannel sound system: “Wooden waves”, video documentation


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Finally I prepared the video documentation of “Wooden Waves”, an installation originally conceived for the beautiful windmill of Harplinge, which is now turned into a hub for experimental arts (HarpArtLab), for the BZZZ! international sound art festival (July 2015).

(You may also take a look at the pictures I uploaded to a previous blog post.)

Eight contact speakers are attached to the floor’s wooden planks.

The listener lays down on the floor, transformed in a resonating surface.

Sound is perceived not only through the ears, but mostly through the body of the listener.

By stimulating the body in 8 different areas, a spatialization of the tactile sensation is put into play. This makes it possible to shift the use of space – typical of the electroacoustic composition approach – from the external dimension of the environment to the internal dimension of the body of the listener.



Touch my string. “Perturbance” for double bass and embedded electronics

Ghost studies, no. 2 “Perturbance” for double bass and embedded electronics

Jonathan Heilbron, double bass

47° Darmstadt Ferienkurse

August 15th, 2014, Kunsthalle Darmstadt


A series of three works with vibration devices embedded in musical instruments has been produced in the frame of the 47° Darmstadt Ferienkurse (“Expanded Music” workshop, coordinated by Simon Steen-Andersen).

The piece shown in the video is the Ghost Study number two, called Perturbance, and written in close collaboration with the double-bassist Jonathan Heilbron.

After a session with the performer, where I recorded a number of percussive interventions he made on the body and strings of the instrument, I reordered these gestures from the most inharmonic to the most stable spectrum (the A string of the double-bass). While building the electronic track (which was supposed to be played back through the vibration speaker), I created different reverberations of the percussive gestures. Some of this reverberations were infinite, and I could use them as static sounds which were triggered by the percussive interventions of the performer. The overall path of the piece lead to the final, loud 55 Hz sine wave emerging from some bowed notes. The A string was thus shaking, and placing the finger on the string made the timbre of the resonance change with the pressure of the finger. At the end of the piece, this resonance seemed to be stopped — as torn off — and re-activated by sudden gestures of the hands of the double-bassist “muffling” the whole instrument. Both this theatrical situation and the reverberations in the previous interventions were quite effective in giving to the instrument a life of its own. The interaction between the performer and the double-bass (the man and the artifact) was not anymore one-directional, but the instrument responded almost consciously to the stimuli of the instrumentalist, and seemed to make decisions of its own.

Being the instrument itself, and not a separated speaker, the resonating surface (electronic tracks can be sent to contact transducer embedded in the instruments) which emits sound, it’s often difficult to perceive (acoustically) the difference between an instrument played by a human and an instrument equipped with vibration capabilities. This way of augmenting the capabilities of an instrument leads to new possibilities in composition for instruments and tape and live-electronics, in a way reconsidering and reframing the live-electronics practice.


Spectral and vibration response tests on wooden planks

These are tests made on eight wooden planks (silver fir), ca. 10 cm wide, 2 cm thick, length variable between 150 and 230 cm. They were placed on a bubble wrap.

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I sent two different signals travelling through the eight vibro speakers (Mighty Dwarfs, attached to the planks via tape). Both signals were controlled via a Max/MSP patch (something between a drum machine and a granulator) which could modulate the pitch and amplitude envelope of each grain, and the duration and tempo over time.

1. Sine wave (varying around 60 Hz) continuously travelling from channel 1 to 8.

  1. Download here the 8-channel file used for the test.
  2. Download here the stereo mixdown of the previous file used for the sonogram.
  3. Download here the stereo recording (ZOOM H4) of the wooden planks resonating.

Sonogram of the original file (stereo mixdown):

Sine - clean


Sonogram of the resonating wooden planks:

Sine - wood

As you can see, the wood resonates with a lot of harmonics and side-noises (other objects were probably resonating as well) even if we send a “pure” sine wave.

2. Sawtooth wave, two sets: one around 60 Hz, travelling from channels 1 to 4; the other slightly higher (one semitone), traveling from channel 5 to 8.

  1. Download here the 8-channel file used for the test.
  2. Download here the stereo mixdown of the previous file used for the sonogram.
  3. Download here the stereo recording (ZOOM H4) of the wooden planks resonating.

https://drive.google.com/file/d//edit?usp=sharing

Sonogram of the original file (stereo mixdown):

Sawtooth - clean


Sonogram of the resonating wooden planks:

Sawtooth - wood