### Will is out of town Friday - His office hours will be canceled - **Class is canceled Friday!** - Take the time to be kind to yourself. --- # What does speech sound like? ### Will Styler - LIGN 6 --- ### Review - Visualizing Sound --- ### "Noise" - Waveform
--- ### "Noise" - Spectral Slice (FFT)
--- ### "Noise" - Spectrogram
--- ### Today's plan: - What do vowels look like? - What do consonants look like? --- # Fundamentals of Speech --- ### Voicing
--- ### Spectrograms show us many evenly-spaced vertical lines - These are individual glottal pulses - Higher pitched voices will have...? - More tightly spaced lines! --- ### Duration /bi/, /bid/, /bit/
--- ### Resonances in the mouth
--- ### You know what's created entirely by resonances in the mouth? --- # Vowels --- ### What is a vowel? * A vowel is voicing passing through (and resonating in) an unobstructed vocal tract! * If we change the position of the tongue, we change the resonances ---
--- ### What is a vowel? A vowel is voicing passing through (and resonating in) an unobstructed vocal tract! If we change the position of the tongue, we change the resonances * Different resonances *filter* the sound differently and determine the vowel quality * **Different tongue shapes create different resonances, and different vowels!** ---
--- ### What do vowels sound like? * We talk about vowel quality in terms of "formants" * These are bands of the spectrum where the energy is strongest * The frequencies of these formants are our primary cues to vowels ---
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Different American English vowels, as spoken by a male speaker
--- ### If the position of the tongue causes formants to appear... - What happens in diphthongs, where the tongue moves? ---
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--- ### Formants alone can be enough for some perception! --- ### Let's listen to some sounds
--- ### Let's listen to some sounds
### Now let's play all three at once!
--- ### Let's listen to some sounds
### Now let's play all three at once!
### Does this help?
--- ### So, we think about vowels in terms of formants ---
Different American English vowels, as spoken by a male speaker
--- ### Vowel formants are reflections of articulations - They vary depending on the tongue's position - ... as well as the size and shape of the talker's head - *Different formants from the same speaker mean different vowels* - ... kind of ---
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--- ## **Vowel perception is really, really hard** - ... so, consonants must be easy, right? ---
--- # Consonant Acoustics --- ### /l r w j/ act a lot like vowels
--- ### Nasals look like quiet vowels
--- ### Fricatives have little black clouds - ... and the cloud is higher frequency as you get closer to the mouth
--- ### Voiced fricatives have little clouds *and* voicing
--- ### For stops, the signal... stops (with voicing)
--- ### For stops, the signal... stops (without voicing)
--- ### Taps are really tricky to spot
--- # Let's Practice! --- ### Animals will finds cute - Chickadees, Cats, Dogs, Pandas, Koalas, Owls, Velociraptors, Woodpeckers ---
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--- ### If you want more of this... - We have a spectrogram reading group! - [Rob Hagiwara's Monthly Mystery Spectrogram Webzone](http://home.cc.umanitoba.ca/~robh/index.html) - They're *really* difficult --- ## "Why all this time on spectrogram reading?" --- ### Speech Acoustics is the basis of automatic speech recognition - If we don't know what words sound like, we can't teach computers what they sound like - Spectrograms give us great information about frequency, power, and time - Similar patterns are easy to confuse for humans and computers - This lets us understand a bit more about how ASR might work --- ## For next time - We'll figure out how computers could possibly do this ---
Thank you!