What do we hear?

• Sound is a compression wave - it only “looks” like a wave if we plot air pressure against time

time ->

Air Pressure

Period - amount of time for one cycle

Frequency = number of cycles per second (1/Period)

Sensing Vibrations

• Inside the cochlea is the basilar membrane• Movement of the oval window causes ripples

on the basilar membrane

Hearing• Detection • Loudness • Localization• Scene Analysis • Music• Speech

Detection and Loudness

• Sound level is measured in decibels (dB) - a measure of the amplitude of air pressure fluctuations

• dB is a log scale - small increases in dB mean large increases in sound energy

• We have a dynamic range that is a factor of 7.5 million!

• minimum sound level necessary to be heard is the detection threshold

• detection threshold depends on frequency of sound:

• very high and very low frequencies must have more energy (higher dB) to be heard

• greatest sensitivity (lowest detection threshold) is between 1000 hz to 5000hz

• Detection can be compromised by a masking sound

• even masking sounds that are not simultaneous with the target can cause masking (forward and backward masking)

• Loudness is the subjective impression of sound level (and not identical to it!)

Detection and Loudness• For example,

tones of different frequencies that are judged to be equally loud have different SPLs (dB)

Detection and Loudness• Hearing loss due to exposure to high-intensity

sounds (greater than 100 dB) is frequency-specific and can last many hours

Detection and Loudness• Incidence of noise-related hearing loss is increasing dramatically• iPods and other “earbud” music players are thought to be partly

responsible• How loud is an iPod?

– maximum volume is approximate but is somewhere between 100 dB (hearing damage in about 2 hours) to 115 dB (hearing damage in about 15 minutes)

• Consequences: difficulty understanding speech, tinnitus, deafness • Your perception of loudness adapts so it’s hard to tell how loud your

iPod is - LOCK THE VOLUME ON YOUR iPOD!

What do we hear?

Documents

“Hear what we say, We want freedom today!” RISING VOICES · RISING VOICES AN ACTIVIST ALBUM BY WILDWOOD 5TH GRADE “Hear what we say, We want freedom today!” A celebration

Do You Hear What I Hear?

Should we see to understand what we hear?

Explanation and Exoneration, or what we can hear

© Positive Approach to Care® to be reused only with ......Why Do We Laugh? Something Seems ‘Funny’ to Us: •What we see •What we hear •What we experience •What we see

Live Sound Training. Essential Question: “How do we get the entire audience to hear exactly what we want them to hear?”

How do we see what we see? How do we hear what we hear? A question that has intrigued philosophers since the beginning of recorded history

Do you hear what I hear? - drclaiborn.info you hear what I hear.pdf · Do you hear what I hear? Some thoughts on “voices” James Claiborn Ph.D. ABPPAuthors: Verner Zenobia B Williams

Teaching for retention: what they hear vs. what we say

Hear what others can’t hear!

Do you hear what I hear? - drclaiborn.info

Why do we hear what we hear? James D. Johnston Chief Scientist DTS, Inc

We retain: 10% of what we read 20% of what you hear 30% of what we see 50% of what we see and hear 70% of what we talk about with others 80% of what we

We want to hear what you think about sentencing for burglary

What could we hear on the empty playground?

Do You Hear What I Hear? - Semantic Scholar You Hear What I Hear? Author Mike

Do You Hear What I Hear - SSA

The Physics Of Sound Why do we hear what we hear? (Turn on your speakers)

Genetic Engineering. What Is This? Do you hear what I hear?

Do You Hear What I Hear? - fccog.org