lec 3 Flashcards
diff bw node and antinode?
- node: where air motion or pressure variation is at a MINIMUM
- antinode: where air motion or pressure variation is at a MAXIMUM
- pressure node = displacement antinode
is the mouth a pressure node or antinode?
node
is the glottis a pressure node or antinode?
antinode
T or F: open mouth + closed glottis results in a 180-degree phase change and the cancellation of some frequencies
true (standing wave)
what kind of frequencies does a clarinet (closed on one end) have? what about a flute (open on both ends)?
- clarinet: odd frequencies only (bc phase cancellation!)
- flute: all frequencies
whats a resonating frequency?
the frequency at which an object vibrates most easily
how do we find the wavelength of the resonating frequency of any tube? what about the actual resonating frequency?
• wavelength of resonating frequency = 4 x the tube length
• resonating frequency = c/4L
the formula for the straight tube resonance model is: Fn = (2n-1) c/4L
why do we need to do 2n-1?
what do we plug in for L here?
- to get odd multiples (because even numbers get cancelled)
- L = 17.5cm (length of adult vocal tract)
using the straight tube resonance model, what do we get for F1, F2, and F3?
- F1 = 500 Hz
- F2 = 1500 Hz
- F3 = 2500 Hz
- this is close to schwa resonance
T or F: when producing a schwa, F1, F2, and F3 occur one after the other
false – occur simultaneously
whats the avg length of a child’s vocal tract?
8.5cm
what happens to resonance frequencies when you speak under water?
in water, resonance frequencies increase (different c)
what are the 3 main elements of linear source-filter theory of speech production (SFT)?
- source (glottal)
- resonator (vocal tract filtering)
- radiation (lip radiation effect)
how many dB decline per octave at the source? how many dB increase due to radiation?
- -12
- +6
what are formants?
peaks of the harmonic spectrum which have been filtered by the vocal tract
