Air Pressures for SpeechVoice

1
Air Pressures for Speech/Voice

• Lab 3

2
Air Pressure

• Pressure force per unit area acting on a surface
• Different units of measurement to suit
  application (cm H20, pascals, etc.)
• U-tube manometer- cm H20
• 7 cm H20 of subglottal pressure indication that
  the air below the larynx exerts enough force to
  hold up a column of water 7 cm high
• Baken (pg. 298-302)

3
Units of Measurement

• cm H20- Centimeters of water
• mmHg- Millimeters of mercury
• d/cm2- Dynes per square centimeter
• Gauges, Absolute, Differential

4
Speech Pressures
Atmospheric

• Subglottal pressure (Ps)
• Intraoral pressure (Pio)
• Atmospheric pressure (P atm)
• Intrapleural (Ppl)

Intraoral
Subglottal
Intrapleural
5
Instrumentation

• Aerophone II
• Mask
• Pitot tube
• Transducer
• Pneumotachograph (flow)
• Microphone (SPL)
• Laryngeal microphone (Pitch)
• (Baken pg.308-331)

6
Calibration

• Flow head calibration
• 300 (speech measures)
• /papapa/-syllable train
• I hear papa popping popcorn-Connected speech
• 1000 (static measures)
• Vital capacity
• Peak flow

7
Measurement Protocol

• Mask placement- Seal
• Pitot tube placement
• Lip closure
• Tasks- /pa pa pa/ or /pi pi pi/
• Intraoral pressure is an estimate of subglottal
  pressure during voiceless stop
• Why voiceless?
• Timing of task
• Comfortable SPL- practice first

8
Laboratory

• Intraoral pressure during consonants
• Use the sample provided in the lab of the normal
  21 year old male stutterer- tie-dye a zoo
  suit
• How can you tell if voicing is present?
• Duration on bottom
• Why is voicing important for measuring pressure?
• Plosives vs. fricatives?
• Co-articulation effects of pressure

9
Laboratory

• Disordered sample
• Clipping
• Irregular waveforms
• High pressure vs. normal pressure

10
Laboratory

• Estimating subglottal pressure with aerophone II
• measuring Pio to estimate Ps
• Perform /papa/ task
• Identify lip opening lip closure
• Flow vs. pressure
• Peak pressure
• Audio record
• release of /p/ and and waveform of /a/

11
Laboratory

• Use the samples to measure pressure in
  comfortable and loud productions
• Also calculate your own peak and mean pressure,
  SPL,record results