Gjallarhorn

Concept: Audialsense (Paul Bavister / Jason Flanagan / Ian Knowles)

Coding: Paul Bavister

2016 saw the unveiling of the reconstructed ‘Denman Horn’ by Aleks Kolkowski. It was once the worlds largest speaker cone at 27ft when it was created in 1929 by Roderick Denman, and laid in the vaults of the science museum for decades until reconstructed in 2014 when it had a two week residency in the Science Museum hosting various musical performances and events. Audialsense were invited to develop content for the horn over the middle weekend of the residency.

We were very lucky to have access to the big engines on permanent display in the museum. We wanted to extract the structural borne noise from the engines and play the sounds back on the Denman horn. However, we didn’t just want to play back the sounds in a straight way, but make the more much more site specific, and in a subtractive way, only play back frequencies into the room that match the resonant frequencies of the gallery space. 

We used contact microphones to extract the sounds from the engines. These are magnetic microphones that pick up material resonances rather than air borne frequencies as typical microphones do. Its worthy of note, that the mechanics who maintain the engines saw us use this technique, and commented that for quick diagnostic purposes, they often use screwdrivers placed onto a surface of an engine, and with the rounded handle firmly inserted in their ears, they can ‘listen’ for any issue that may be invisible to the eye, but only revealing itself in sound.

The raw recordings of the work can exclusively be heard on Touch Radio 107/Audialsense: