Week 7 Flashcards
(11 cards)
What are the different ways to differentiate sound?
Pitch (f0), loudness (intensity), and voice quality (vocal tract shape). All of these are independent from each other such that any two sounds that vary along one of these dimensions will be different sounds.
What is the Source Filter Theory?
It is a theory of how speech is produced, or how sound can be manipulated.
What is the source in the Source Filter Theory? The filter? The output?
The source is vibrating vocal folds. The filter is the vocal tract. And the output is sound.
Describe the filter of the Source Filter Theory.
The filter takes a wave as input, sustains certain frequencies while suppressing others, and produces an output wave with different frequency components.
What are the different types of filters?
The two types of filters are man-made or electronic filters and filters that occur naturally in a system that can be set to vibration. Low pass filters - only let low frequencies through. High pass filters - let only high frequencies through. Band pass filters - let a combination of the two through.
What is the transfer function of a filter?
The transfer function of a filter describes how the spectrum of sound will be changed by passing it through the filter.
What is a resonator?
A resonator is a type of filter created by a physical structure (ex: room, hallway, pipes, cave, vocal tract, etc.). The transfer function of a resonant filter is usually peaked like a sharp band pass filter. The center frequency is the only frequency that is allowed to pass unimpeded.
What are formants?
The resonant frequencies of the vocal tract are called formants. We can see them as the peaks in a spectrum. With vowels, the frequencies of the formants determine which vowel you hear and are responsible for the differences in quality among different periodic sounds.
How are vowels described?
We use the position of the tongue and the shape of the lips to describe vowels. The tongue body can move up or down (tongue height), the tongue can move forward or back (tongue frontness/backness), the lips can be rounded or not (lip rounding).
F1, F2, F3, and their relation to vowels.
The first formant (F1) is inversely related to vowel height, the higher the vowel, the lower the first formant. The second formant (F2) is related to degree of backness. The more front the vowel, the higher the second formant. The closer F1 and F2 are to each other, the more back a vowel is.
