SOUND INSTALLATION  - MA FINE ART (KARL HOBBS) PROJECT

TX: 17th July 2006

OVERVIEW

Initial survey of the room – referring to dimensions as supplied. The space indicated is 5.5m x 6.8m x 3.8m.  The event to be recorded is a sequence of low-level footsteps tracing a pathway across breezeblocks.  The sequence lasts approximately 2mins 30s and involves walking around two metal stools placed on the installation. 

The brief was to achieve a surround sound effect that allows the viewer to experience the event of footsteps in the space, being able to walk around and feel that at any point in both rooms that a tangible event is taking place.

It was also indicated that as far as possible, the event recording must be a true representation of the moment at which it is captured, inclusive of resonance.

EQUIPMENT

Marantz Hard Disc Recorder.  2 x AKG dynamic microphones (power).  Sony MD  + Sony 120 degree microphone (to capture ambient room noise). Cabling. Tape.

Panasonic SHC660 Surround Sound DVD Unit – 5 x speakers (L, R, LS, RS, Centre) plus sub woofer. Speaker stands x 4. For broadcast in space.

TESTING/PROBLEMS

Microphones placed to capture L – R stereo recordings of the event had to be taped down to prevent rattle and stools dampened between the legs and breezeblock contact point to lessen the vibration of movement.   3 stages of recording:

1. Ambient room noise recorded directly overhead from the midpoint of the installation.

2. L-R Microphones placed on stools as indicated in diagram. (chairmike)

3. Event recorded using speaker positions LR1, LR2 to compare to chairmike recordings. (LR1/LR2 recordings).

Test recordings show that the space is very resonant. Ambient noise from cars/school and people working in building reduced at source by ensuring silence from the floor above and recording out of school hours. Any other ambient noise to be reduced post production.

POST PRODUCTION

Recordings transferred to Adobe Audition. After cleaning up the audio by taking out the higher hiss frequencies, two versions of the recordings were taken back to the space to broadcast and evaluate.

1. Chairmike: Good representation of event.  Clarity of footfalls good in space and true stereo broadcast L-R.
2. LR1/LR2:  It was felt that these recordings were too broad in spectrum and although included a wider capture of the space in which the recording and event took place, that as a broadcast it was not effective. 

In both cases, the broadcast of the original recording was doubly resonant. That is, the original resonance is again broadcast in the same space.  It was felt that this was not effective and it was agreed to use the chairmike recordings and reduce the ambient sound of the room before processing for broadcast. 

BROADCAST

The DVD unit is set up as indicated in the diagram to minimalise the impact on the installation.  Speaker stands are in the corners of the room and the sub woofer placed in the window alcove.  This creates an optimum listening point while viewing the sculpture, which is the natural entry point in to the room. 

The DVD unit is capable of bouncing a stereo recording to 5.1 with some adjustment to the volume and bass/mid/treble levels. 

Final recordings of chairmike are looped to an hour in duration and are repeated by the DVD player.  Each sequence is linked by an ‘ambient' pause lasting 10s – a repetition echoed by the event.  This ambient pause creates a tension in the listener, which supersedes the silent pause tested in an earlier version.

Final Processing and TX CDs:

1. Chairmike De-hiss.  Attenuated microphones.  Sound rotated 360 degrees.
2. Chairmike De-hiss. Flat sound. No 360 degree rotation. (Use DVD to bounce to 5.1)
3. Chairmike De-hiss. Low level band pass frequency cut at 200Hz (filter). Sound rotated 360 degrees.