Slides for HCICourse.com

1. the ear and sound

2. sounds
second sense?
particularly important for speech
less used in user interfaces
partly because annoying for others
because less directional more
diffuse
strength and weakness

3. the spectrum of sounds
sounds vary in:
pitch (frequency)
volume
timbre ... the ‘shape’
violin vs. big bass drum

4. the ear
sensitive from ~20Hz to ~ 20KHz
changes with ageing
balance organs
also in the
inner ear
image: http://en.wikipedia.org/w/index.php?title=File:Anatomy_of_the_Human_Ear.svg

5. two ears and the pinna
two ears
stereo sound
=> left-right detection
pinna (visible ear!)
directional
changes shape of sound
=> full 3D sound
image:

6. time and space
vision: movie or static picture
sound: no ‘static’ sound
always about change
vibration, movement, pressure waves

7. time and space
binaural hearing
distance between ears ~ 30 cm
speed of sound ~ 340 ms
delay left–right ~ 1 ms

8. time and space
wavelengths
middle C in piano
frequency: 261.6 Hz
wavelength ~ 1.3 metres, 4
½ feet
affects propagation in spaces, resonance

9. in the interface
simple sounds (beep, ring, and buzz)
attention grabbing and feedback
ecological (thump and gurgle)
what is happening
speech and music:
recorded (download & play)
live (streaming movie) delays, gaps,
interactive (Skype and video calls) and jitter

10. the phone ...
multi-tap with simulated key click
to type f = ddd
three ‘d’ presses
kept doing four
but only with sound on
(delayed) aural feedback
overcame physical feel

11. setting the mood
the movie soundtrack
may not notice at the time
engagement in video games and VR
the sub-seat woofer!

12. attention and background
can focus aural attention
the cocktail party effect
but also general sense of context
Arkola
and can grab attention
big bang or softly whispered
name