When learning how to sing better, it is critically important to remove all unnecessary tension and strain from the jaw and throat area in order to have a clear and free sounding tone. However, bad singing habits often leave us using muscles that hinder vocal freedom. One muscle in particular that causes great tension is the digastric muscle.
The digastric muscle is the small muscle located under chin that is activated when swallowing. So that you may see and understand for yourself, place your finger under your chin and swallow. As you swallow, do you feel something pushing down on your finger? If you didn’t, then you are quite lucky and do not suffer from digastric muscle tension. However, if you did feel tension and pressure on your finger (most of us do), then you suffer from some sort of digastric muscle tension. This excess tension under the chin causes singers to tighten up the jaw and raise the larynx when attempting to sing high notes, which helps give way to a very squeezed and painful sounding tone.
Since we must swallow everyday, there will be no way in which we can completely disregard the digastric muscle. However, we can use different practices and techniques that can remove the digastric muscle from the singing process. Since tone is produced at the vocal cords, it becomes vitally necessary to strengthen these folds so that the burden of tone falls upon them and not the digastric muscle or outer throat muscles. While exercising the vocal cords by using scales is beneficial, it is not sufficient enough to teach the vocal cords how to function to their full capacity. Singers must work and strengthen the thin edge of the vocal cords in order to begin the process of disengaging the digastric muscle from the singing process.
The thin edge of the vocal cords can be activated by using specific vocal exercises. An excellent exercise for training the thin edge is the use of a squeaky sound on an octave scale using a staccato approach. Place you thumbs under your chin and apply pressure (not so much pressure to where it hurts, but enough pressure to keep the digastric muscle from causing extra tension) to your digastric muscle and make a squeaky, vocal fry sound. This light, squeaky sound activates the thin edge of the vocal cords and forces them to produce tone. Exercising and strengthening the thin edge is crucial when blending chest and head registers for higher notes.
Another good exercise to work out the thin edge is sticking your tongue out of your mouth (all the way) and saying “aaaah” (it will have a nasal ring to it). Practice this on an octave scale using slides between the aaah’s (so it would be written out like this: aaaah-a-a-aaah-a-a-aaaah). Sticking your tongue out of your mouth stops the digastric muscle and other throat muscles from causing tension, thus making the edges of your vocal cords do the work to produce your tone.
The digastric muscle can be a pain to disengage. You may need to practice singing with your fingers under your chin for some time to get used to the feeling of not using your digastric muscle. The good thing is that when you are used to singing without the strain of the digastric muscle, you will notice when it tries to creep in and “help” you out. Train yourself to sing without that pesky muscle, and your vocal cords will reward you for it.