Loudness and Pitch

Intensity of the sound

When the volume on a stereo amplifier is increased, what physical characteristic of sound is being increased?

physical measurement

Is sound intensity considered a physical measurement or a perceptual measurement?

Sound Level Matter

What does SLM stand for in acoustics and psychoacoustics?

Intensity of Sound

Physical magnitude or strength of a sound

Physical magnitude

an objective, measurable property of a sound, such as its power or pressure

sound power

one way of expressing the physical intensity of a sound

sound pressure

a physical measure of sound intensity that can be quantified with instruments

volume increase (stereo amplifier)

increasing the volume on a steroid amplifier increases the intensity of the sound being produced

sound level meter (SLM)

an instrument used to measure the intensity or sound level of a sound

microphone

a device that detects sound and is used with a sound level meter to measure sound intensity

objective measurement of intensity

sound intensity can be directly measured using a microphone and sound level meter rather than relying on a listener’s perception

loudness

The perception of intensity is called?

Intensity Measurement Example

Turning up the volume on a stereo amplifier increases sound intensity, which can be measured using a microphone and SLM

phon

unit of loudness level

1000

A phon is equal to an SPL of _______ Hz tone

50 phons

1 K at 50 dBSPL =

Phon

follows a dB scale at level 1K

Equal Loudness Curve

At low loudness levels curves are similar ins shape to the minimal audible field, thus more intensity is needed to achieve equal loudness for lower frequencies than for higher ones.

U-shaped

The the shape of the Equal Loudness Curve, reflecting greater sensitivity in the mid-frequencies and reduced sensitivity at very low and very high frequencies.

Subjective Loudness Scalling

shows how the loudness perception is related to the intensity of the sound stimulus, since we are interested not only in the loudness of a particular sound, but also in how much louder one sound is than another

sone

unit of loudness of a 1000 Hz tone presented at 40 dBSPL is 1 _____.

levels

While phons show the function of stimulus intensity, sones show the function of loudness ____

2 times as loud

assign value to 1 sone use as reference then 2 sones will be at an intensity that sound __ _____ __ ____ as the reference.

40

1 sone = ___ phons

9 dB

How much increase in SPL usually causes a doubling of loudness?

pitch

perceptive of frequency as the psychological correlate of frequency

mels

What is pitch measured in?

2000

The frequency twice as high as 1000 Mels has a pitch of _____ mels.

1000

Frequency of 1000 Hz produces a pitch of _____ mels, but the farther one goes either up or down from that frequency scale, the less agreement there is between frequency and pitch.

doubles

Tripling the frequency from 1000 to 3000 only does what to the pitch?

non linear

Frequency and pitch relation is

20

The normal ear is aware of pressure changes at frequencies below ___ Hz.

Tonality

Frequencies below 20 Hz do not produce a perception of ______.

Tonality

emerges at 20 Hz and the perception continues to about 20,000 Hz.

intensity

Although the primary determiner of pitch is frequency, the _____ of the sound may influence the pitch that one perceives.

3000 Hz

Increasing the intensity of the tone increased its pitch for frequencies ______ and above.

1000 Hz

Increasing the intensity of the town lowered its pitch for frequencies _______ and below/