230 likes | 539 Views
MUSIC 318 MINI-COURSE ON SPEECH AND SINGING. 1. SPEECH PRODUCTION. Science of Sound, Chapter 15 The Speech Chain, Chapter 4 The Science of the Singing Voice ( Sundberg , NIU Press, 1987). THE VOCAL ORGANS. VOCAL TRACT WITH SOFT PALATE LOWERED FOR BREATHING. BREATHING AND AIR FLOW.
E N D
MUSIC 318 MINI-COURSE ON SPEECH AND SINGING 1. SPEECH PRODUCTION Science of Sound, Chapter 15 The Speech Chain, Chapter 4 The Science of the Singing Voice (Sundberg, NIU Press, 1987)
BREATHING AND AIR FLOW LUNGS HAVE NO MUSCLES ; BREATHING IS ACCOMPLISHED BY CHANGING THE SIZE OF THE CHEST CAVITY IN TWO WAYS: 1.DOWNWARD MOVEMENT OF THE DIAPHRAGM TO LENGTHEN THE CHEST CAVITY 2. ELEVATION OF THE RIBS TO INCREASE THE FRONT-TO-BACK THICKNESS TWO MUSCLE GROUPS ARE USED: EXTERNAL AND INTERNAL INTERCOSTALS THAT EXPAND AND CONTRACT THE RIB CAGE 2. ABDOMINAL WALL AND DIAPHRAGM WHICH CHANGE THE ABDOMINAL CAVITY
BREATHING TECHNIQUES SINCE BREATHING IS DONE WITH 4 MUSCLES, THERE ARE SEVERAL DIFFERENT TECHNIQUES THAT CAN BE USED (SUNDBERG, 1987) “BELLY IN” TECHNIQUE: THE EXPIRATORY INTERCOSTAL AS WELL AS THE DIAPHRAGM MUSCLES ARE STRETCHED AND CAN THUS BE EFFICIENTLY RECRUITED IN ORDER TO PROMPTLY INCREASE SUBGLOTTAL PRESSURE. “BELLY OUT” TECHNIQUE: IF COMBINED WITH ELAVATED AND OUTWARD POSITIONING OF THE RIB CAGE WALL, THE INTERCOSTAL MUSCLES ARE STRETCHED, AS ARE THE ABDOMINAL WALL MUSCLES, BUT INSPIRATORY EFFORTS ARE LIKELY TO BE NEEDED.
SUBGLOTTAL PRESSURE SUBGLOTTAL PRESSURE GENERALLY REFERS TO “OVERPRESSURE,” THE AMOUNT BY WHICH THE PRESSURE BELOW THE GLOTTIS EXCEEDS ATMOSPHERIC PRESSURE. THE MOST ACCURATE WAY TO DETERMINE SUBGLOTTAL PRESSURE IS TO INSERT A THIN NEEDLE INTO THE TRACHEA, AND A FEW SPEAKERS AND SINGERS HAVE SUBMITTED TO THIS METHOD. AN INDIRECT METHOD IS TO CLOSE THE LIPS AND OPEN THE GLOTTIS, SO THAT MOUTH PRESSURE IS ESSENTIALLY EQUAL TO SUBGLOTTAL PRESSURE. THEN THE SUBGLOTTAL PRESSURE CAN BE DETERMINED BY THE DROP IN ORAL PRESSURE DURING THE PRODUCTION OF THE CONSONANT /p/.
SUBGLOTTAL PRESSURE DURING PHONATION SUBJECT ASKED TO TAKE A DEEP BREATH AND COUNT FROM 1 TO 32. TO THE LEFT OF THE VERTICAL LINE, THE NET MUSCULAR FORCE IS INSPIRATORY; TO THE RIGHT IT IS EXPIRATORY. THE SUBGLOTTAL PRESSURE Ps REMAINS REASONABLY CONSTANT THROUGHOUT THE ENTIRE PROCESS. (SUNDBERG, 2007).
SUBGLOTTAL AND ORAL PRESSURE AND AIR FLOW AIR FLOW, SUBGLOTTAL , and oral PRESSURE VARIATION WHILE SPEAKING THE PHRASE “phonetic aspects”
THE LARYNX • BACK VIEW • (b) SIDE VIEW
VOCAL FOLDSCONTROL OF THE GLOTTAL OPENING BY THE ARYTENOIDS
GLOTTOGRAMS (GLOTTAL FLOW WAVEFORMS) SHOW HOW THE AIR FLOW THROUGH THE GLOTTIS VARIES WITH TIME
GLOTTAL MASK WITH INVERSE FILTERING SUBJECT PHONATES THROUGH AN ACOUSTIC RESISTANCE, SO THAT MICROPHONE MEASURES GLOTTAL FLOW INVERSE FILTER HAS A TRANSFER FUNCTION THAT IS THE INVERSE OF THE VOCAL TRACT TRANSFER FUNTION . THUS IT MINIMIZES THE EFFECT OF THE VOCAL TRACT AND DISPLAYS THE GLOTTAL FLOW AS IF THERE WERE NO VOCAL TRACT.
GLOTTAL WAVE FORM SPECTRUM THE FLOW OF AIR THROUGH THE GLOTTIS IS ROUGHLY PROPORTIONAL TO THE AREA OF THE GLOTTAL OPENING. FOR NORMAL PHONATION, THE TRIANGULAR WAVEFORM OF THE GLOTTAL FLOW IS COMPOSED OF HARMONICS THAT DECREASE AS 1/n2 (AT A RATE OF -12dB/OCTAVE.
FLOW GLOTTOGRAM AND ITS DERIVATIVE DERIVATIVE SHOWS THE RATE OF CLOSURE OR OPENING OF THE GLOTTIS (WIGGLES ARE AN ARTIFACT DUE TO IMPERFECT INVERSE FILTERING)
GLOTTOGRAMS FOR LOUD AND SOFT PHONATION LOUD PHONATION REQUIRES A RAPID CLOSURE OF THE GLOTTIS
SOURCE/FILTER MODEL OF SPEECH THE SOURCE/FILTER MODEL DESCRIBES SOUNDS OF SPEECH AND SINGING AS A PRODUCT OF SOURCE AND FILTER AND RADIATION EFFICIENCY SPEECH SOUND=SOURCE x FILTER x RADIATION EFFICIENCY IF EACH OF THESE QUANTITIES IS EXPRESSED IN DECIBELS (dB), THEN THE CONTRIUBTIONS ARE ADDED RATHER THAN MULTIPLIED. THE SOURCE FUNCTION DECREASES IN STRENGTH ABOUT 12 dB/OCTAVE. THE RADIATION EFFICIENCY OF THE MOUTH RISES ABOUT 6 dB/OCTAVE, SO THE NET DECREASE DUE TO THE 1ST AND 3RD TERMS IN THE EQUATION IS ABOUT 6 dB/OCTAVE
WAVEFORMS AND SPECTRA OF TWO VOWELS /a/ (ah) /u/ (uh)