Mix Ideas presented at PAS6
Weekly Teaching Tip – Oct. 22, 2012
Herbst: There is a good case to be made for singing with the vocal folds adducted; tissue is a good conductor, air is not. The laryngial nerve controls 2 muscles (TA and CT) – it is difficult to learn to coordinate letting go of one and activating the other. There is also help from the IA, PCA and LCA muscles (stiffening of the vocalis muscle) which helps connect the registers.
Miller: When the vocal tract is closed it is a superior resonator. There are also advantages to singing with a higher closed quotient. The closed quotient need not change with volume differences.
Adduction and sub-glottal pressure can be separated:
Belt – high adduction, high sub-glottal pressure (stressed voice)
Falsetto – low adduction, low sub-glottal pressure
Mix – high adduction, minimal sub-glottal pressure
Noe: Demonstrated that “vowel centering” helps boost higher harmonics creating a more vibrant and ‘brighter’ sound (Italian) that many people seem to enjoy more than the ‘heavier’ sound (German). “Vowel centering” encourages singing in a mix rather than ‘pulling up’ chest.
Bozeman: As the pitch rises to within an octave of the normal F1, the voice ‘turns over”, timbre goes from open to closed and the vowel modifies passively. (The singer doesn’t need to consciously change the vowel.)
Titze: Chest voice is TA dominant with the full thickness of the vocal folds touching. Falsetto has only the top part of the vocal folds touching. Mix has a medium amount of the vocal folds touching. This is why mix has a “chest-like” quality along with volume and strength while enabling the vocal folds to vibrate rapidly enough to achieve higher pitches. In “chest” the TA muscle is tight and the mucosa is looser. In mix, the TA becomes ‘looser’ and the mucosa becomes tighter.
Scientific definition of Mix:
Balance of adduction (top and bottom of vocal folds)
Balance of tension between the vocal ligament and the TA muscle
Balance of energy in the lower frequency harmonic
Semi-occluded vocal exercises are good for developing mix (phonate through a straw) because it helps keep the first Formant below all harmonics (The 2nd harmonic is not boosted as in belting), and it spreads the vocal folds apart so that the top and bottom are equalized. The thinner the straw, the more the occlusion (thinner straw creates a stronger occlusion).
(Here is some follow up to this week’s teaching tip.)
Question: Hi Dean – Quick question: Is the singer literally using a straw to phonate through? Years ago I studied with a teacher who had me vocalize with a straw. It was an amazing tool.
Answer: Yes, that is exactly what it means. Dr. Titze has had a lot of success using this (as has many other teachers).
Question: thank you for the info. I think understanding (or at least trying to understand!) the science really helps teaching/singing. Would you mind addressing one comment sited below please?
Dr. Miller: “When the vocal tract is closed it is a superior resonator”
Do we close the vocal tract by modifying (or centering) the vowel? Thank you!
Answer: No, we close the vocal tract by keeping the vocal folds together. Opposed to some techniques (usually more classical in nature) that encourage the singers to “let go” of the vocal folds, or at least get a “lighter” connection so that it is easier to move into their higher tones. Yes, it might make it easier to move into the higher notes, but the sound isn’t nearly as good as when the vocal folds are together (closed). When the vocal folds are closed there is a lot of ‘feedback energy’ getting sent back down the vocal tract thus making it a better resonator. The sound is fuller, richer and better because of this.
Question: Guess I’m having some confusion about the terms, or use of them. OK, so are the terms “vocal tract” and “vocal folds” interchangeable in this case, or is keeping the vocal folds together what “closes” the vocal tract, and is “closing the vocal tract” the same as “shortening the vocal tract”?
Answer: No, the vocal tract is the tube that begins at the larynx (the vocal folds- where the sound is created), and ends at the lips (where the sound escapes). Bringing the vocal folds together (closed quotient) ‘closes’ the vocal tract on one end, sending all of the sound up the vocal tract and out of the mouth. Thus, closing the vocal tract, or bringing the vocal folds together creates a better resonator for the sound.