Midterm Pitch Flashcards
Pitch
The psychological correlation of frequency
How pitch is estimated
Method of fractionation
Method of fractionation
Present a tone and have participant Adjust a test tone to be half the pitch, this allows estimation of a pitch scale
Who established the Mel scale
Stevens et. al. In 1937
Mel scale
An arbitrary value
1000 mels is the pitch of a 1000 Hz tone
Does not correspond with musical scale or change in frequency
Factors that affect pitch
Intensity
Duration
How does intensity affect pitch
Pitch of a Puretone is affected by intensity of the signal, not true of complex tones
At 30 dBSL matches were easy
At 50 and 70 dBSL frequencies above and below 2500 Hz required changing the frequency to match the pitch, changes were most dramatic about 2500 Hz
How does duration of effect pitch
The onset of a pure tone is not instantaneously accompanied by a perception of pitch, there is a minimum duration of time needed for pitch
The shorter the duration of the stimulus new large or the change change in frequent (Double at 100 ms, triple at 50 ms)
What are clicks
They occur with tonal durations of a few milliseconds
Click-pitch
Describes the gradual perception of pitch as duration is increased
What is the minimum duration of a stimulus for perception of tonality
250 msec
Theories of pitch perception
Place theory
Temporal theory
Place theory
Sound entering cochlea undergoes a form of spectral analysis in ear, region of the basilar membrane corresponding to the maximum displacement excites neurons in that particular region
Temporal theory
Pitch is perceived by pattern of neural responses of folk by the stimulus
500 Hz has a period of 2 ms- Phase locking occurs every 2 ms the neuron will create an action potential for 500 Hz
Beats
When the frequency of two tones are close we perceive audible beats
These occur since there is an overlap of excitation patterns in cochlea, but also small differences in phase and these patterns
We hear a single tone with small fluctuation in level
