Ultrasound instruments

© 2013 John Driscoll

 






SPEAKING IN TONGUES is a set of evolving custom-built ultrasonic instruments for both performance and sound installation.  They are designed using ultrasonic feedback that is disturbed by small amounts of physical movement.  Each instrument creates one or two ultrasonic feedback fields in either the 25khz or 40khz range.  These ultrasonic feedback tones are heterodyned down into the audio range through a microphone pre-amp. (see Fig. 1)














Fig. 1   Ultrasonic Instrument - Generalized Diagram


These signals are then processed through impulse responses derived from resonant physical objects imparting a novel harmonic transformation. It is a hybrid system with signal generation being analog, motion control digital, and digital output processing.


It is essential to have the four instruments used simultaneously as a chorus with individual voices to give a musical variety and to generate a wide range of tones.

(see figs. 2,3)






                                       



Fig. 2  Slow Motor Foil                 






Fig. 3     X/Y Servos                       Animated Servo Foil                  Spring Mounted Foil







They are controlled by a combination of methods including:

1)Robotic control of moving foil reflectors with servo motors, Arduino, LEAP 3D controller, Wii Nunchuck, and custom Max/MSP and Arduino IDE software for control of speed, direction, and patterns.

  1. 2)Manual manipulation of a spring-mounted foil reflector


The Max/MSP control software is designed to record movement gestures and play them back in a sequence, or default to manual control using either a LEAP 3D controller, or a Wii Nunchuck when either controller is activated.








The technical requirements for demonstration/performance of the ultrasonic instruments are:


SPONSOR SUPPLIED:

  1. 1)A two channel sound system - amplifier/speakers (min 12” - 15” preferred) to  handle low frequencies (incl. speaker wire)

  2. 2)One 6’ table to accommodate setup of the four instruments

  3. 3)AC power and power strip (115 V AC)

  4. 4)Two XLR cables (to amplifiers)

  5. 5)Two channel direct box


ARTIST SUPPLIED:

  1. 1)Ultrasonic instruments (w/Arduinos, LEAP controller, Wii Nunchuck) (4)

  2. 2)Arduino power supplies (3)

  3. 3)Tascam US-1800 8 channel interface

  4. 4)MacBook Pro (w/Arduino IDE, Max/MSP)

  5. 5)Ultrasonic reference oscillators (4)

  6. 6)Mic Pre-Amp channels & power supplies (6)

  7. 7)Two Korg Nano Kontrol midi controllers

  8. 8)Samson MixPad 12 mixer


SETUP TIME: Minimum 1 1/2 hr. (w/sound check)


For Video:  Speaking in Tongues (Ultra Video)


 

INSTRUMENT DESC.
INSTRUMENT CONTROL

TECH.  REQUIREMENTS
INSTRUMENT PHOTOS