How can opera singers sing so loud? By training their diaphragm, their lungs, using their mouths to amplify the sound as much as possible, and adjusting the frequency of the sound they are making.
Opera singers are louder than the average person, but they also have a way of making their voices easier to hear, and that is to do with the pitch. We’ll look at that later. First, how do we sing? It starts with air. Our diaphragm pulls downward, making more space for the lungs to expand. The diaphragm is a muscle, but it doesn’t pull the lungs. It contracts, making the chest cavity larger, and creating a vacuum. This vacuum is an area of very low pressure and air is pulled out of the atmosphere into our lungs to equalize the pressure. When we breathe out, the diaphragm relaxes and the air is pushed out. The breath goes up the trachea and enters the larynx, which is where the vocal cords are. The vocal cords are made of muscle fibers that are suspended in the larynx by a ring of muscles around them. If you are just breathing in and out, the vocal cords open in the middle to let the air through. When you are talking or singing, they come together and the air flow makes them vibrate. Air from the lungs passes rapidly through the vocal cords and creates low pressure. This pulls the bottom vocal cords closed, followed by the upper ones, and cuts the air off. The pressure increases and the vocal cords open again so the process can repeat. This happens very quickly and is the vibration that we use as sound. By using the muscles around them, you can change their length and alter the pitch at which they vibrate. When they are shorter and thicker, they are under more tension and they produce a high-pitched sound. When they are longer and thinner, they are under less tension and they produce a low-pitched sound. The only difference between speaking and singing is that when we speak we are not usually too concerned with the pitch of what we are saying, although when we sing the pitch is very important.
So, how do opera singers get so much volume? The first thing they practice is their breathing. They need to be able to get more air into their lungs to have enough breath for long notes. They need to be able to pull their diaphragm lower so that they breathe all the way down into their lungs. When we talk, we generally just use the air from the upper part of our lungs. If you want to project your voice, you need to be able to use all of the air down to your stomach. This can all be improved with practice and with posture. Good opera singers stand as straight as they can to keep their torso stretched. Opera singers try to move as little as possible, if it can be helped, so that they have more air for singing.
The second thing they do is to use their mouths as an amplifier. When we speak, the sound comes out of our voice box and we use our tongues, mouths, and the back of the throat to amplify our voices. We can do this very successfully, as you will know if you have ever been yelled at by someone. Opera singers raise the soft palate at the back of their throats. This prevents the sound from going up through the nose and makes it richer while allowing it to resonate more. This is not easy to do and requires a lot of practice, but it will give the voice more volume.
The third thing opera singers use is a higher frequency. All musical instruments resonate at a certain frequency for each note that is played. Most instruments in the orchestra don’t reach much higher than a frequency of 2500 Hz. Opera singers train their voices to have a lot more power in the range of 2500 to 3000 Hz, which means their voices are not competing with the sound from the orchestra, but are almost floating over the top of the orchestra. This makes it much easier for the audience to hear them and it makes their voices clearly stand out. It is not so much a case of more volume as more power and pitch.
Opera singers also make use of the acoustics in the opera halls they sing in. They are usually designed to carry the singer’s voice and to have it reach all the seats at roughly the same time. Another task in designing an opera hall is to remove unnecessary echo and reverberation. This is done with the shape, but also with the materials that are used. All of these things go into making an opera singer’s voice so loud. And this is what I learned today.
Photo by Joseph Phillips: https://www.pexels.com/photo/sydney-opera-house-sydney-australia-3753589/
Sources
https://issuu.com/bostonlyricopera/docs/giulio_cesare_r3_page/s/10637295
https://www.linkedin.com/advice/0/what-some-common-voice-projection-mistakes
https://my.clevelandclinic.org/health/body/24456-vocal-cords
https://medlineplus.gov/ency/imagepages/19380.htm
https://www.scientificamerican.com/article/expert-opera-singer/