What does Semi-Occluded Vocal Tract mean?
Semi-occluded means partially blocked, and the vocal tract is what we call the space between the vocal folds and the lips. Semi-occluded vocal tract (SOVT) exercises involve partially blocking the vocal tract, which limits the airflow and helps to relax the vocal folds.
What is the benefit?
Many singers use more air than they need when singing. Too much air pressure below the vocal folds means that the vocal folds are closing more forcefully with each vibration, which can increase the risk of vocal fatigue or injury. Optimizing the airflow to be more efficient allows the vocal folds to relax, as well as encouraging better breath control.
What are the most common types of SOVT exercises?
- Straw Occlusion (also called Straw Phonation)
- Mmmmm / Nnnnnn / Nnngggggg / Vvvvvvvv
- Lip Trills /Tongue Trills / Rolled “R”
How does Straw Occlusion work?
Just hold a straw between your lips and sing! Keep your lips closed around the straw, and make sure that air is not escaping through your nose. Focus on keeping a smooth and steady flow of air through the straw as you vocalize. It may feel difficult at first if you are used to singing with much more air. If your voice feels tense, you may want to alternate between straw occlusion and lip trills at first.
Other variations…
Paper cup – Poke a hole in the bottom and then put the rim of the cup against your face and sing. This allows your mouth to open wider, which can be helpful for higher notes or belting.
Hand – No props needed for this one– just place the back of your hand against your mouth. A little bit of air will escape around the edges of your mouth
When should SOVT exercises be used?
SOVT exercises are recommended as part of a daily vocal workout routine. They are beneficial as part of a warm-up and cool-down, and for troubleshooting vocal issues that come up when working on songs.
Straw occlusion can be used to minimize fatigue during long rehearsals, or as a “reset” during breaks when practicing or performing.
Straw occlusion is also great if you want to sing without making too much noise– perfect for travelling, or when your housemates are asleep!