How Your Voice Can Break a Wine Glass
Enrico Caruso Breaks Wine Flute With His Voice
Enrico Caruso, the great "Italian Tenor" of the early 20th century, was the first person to break a glass using only his singing voice. He did not set out to deliberately do this. It happened at a precise time when all conditions were perfect. Both his vocal range and his ability to sustain his tone long enough, along with correct resonation for projecting sound, attributed to this feat.
Adding to this, the glass was a delicate, crystal champagne flute, with a certain frequency. The great Caruso possessed all the right vocal faculties to match the frequency of the crystal glass exactly.
Some argue that this is a myth. I believe it is true. Knowing the science and technique of the human singing voice and its capabilities, it makes perfect sense to me.
The Great Tenor Enrico Caruso
Singing Opera Is Not a Requirement for Breaking a Glass
Now that you have heard one of the greatest voices of all time provided by the above video, you can appreciate on some level the acoustical properties of the singing voice. These properties are exactly what is needed to shatter a glass (but not any glass).
The finer the crystal, the greater the resonating factors. This makes it possible for the high-pitched singer to match the vibrations of the glass. Furthermore, it is not necessary that one sing opera in order to break a glass. In fact, you don't have to be a singer at all. As I said earlier, it's the set of vibrations causing acoustical resonating qualities of the voice to match the exact frequency of the glass that causes it to break.
Singers may find it easier to complete this experiment because their voices are trained. But, as you will see in the video below, the young boy did not have a trained singing voice.
The key here is resonation. Let's examine just what resonance is and how it works.
What Is Vocal Resonance?
All objects contain a natural frequency that they vibrate from. This is called "resonance frequency." Two words that stand out for understanding how resonance works are force and energy.
In order to induce resonation in an object, there must be a force to pull it back to its starting position with the right amount of energy to keep the object vibrating. It will be your very own voice and the resonance it contains to cause the right amount of vibrations needed.
Therefore, the vibrations of one object (in this case the voice) causes a second object (the wine glass) to start vibrating (resonating).
I sometimes use my grand pianos' sounding board, with the strings in full view, to demonstrate resonance frequency. This is how it works.
How Resonance Frequency Works
- Sing into the piano where the strings are exposed. (Sing the vowel Ah using full volume.)
- Be sure to sustain the tone using plenty of breath support
- The more open the mouth position, the better.
- As you sing into the piano, notice the strings vibrating when you sing their resonant frequencies.
What Causes a Wine Glass to Shatter?
To understand how a wine glass can shatter from the singing voice, it is helpful to first learn how the wine glass itself resonates. So, stay with me here. Let's take a look at the six faculties you'll need.
Six Faculties That Cause a Glass to Shatter
- Medium—This is what the sound is traveling through. (In this case, the wine glass with a stem.) The finer the glass (crystal), the easier it will shatter. Medium is just a fancy word for an object, so never mind if you aren't familiar with it.
- Sound Intensity—You need some kind of physical property measured in decibels, which are referred to as "sound intensity." So, again, this is simply a scientific name and makes no difference.
- Amplitude—The term for the height of a sound wave is called amplitude. You may already be familiar with this term, especially if you're a musician. Think of it like this. If two sounds are the same distance away, the one with the largest amplitude will be the loudest. Easy, right?
- Wavelength—This is the distance from one peak of the wave to the next peak. Perhaps visualizing ocean waves brings this term closer to home.
- Pitch—This is a musical term that relates to the frequency of the vibration. Pitch is also the highness or lowness of a tone. This is very important to understand because during the experiment the pitch of the glass and the voice must match exactly.
- Harmonics—Let's think of a stringed instrument. There can be more than one wave pattern achieved depending on the harmonic structures of the sound. A guitar, bass, violin, piano, cello, and viola are all stringed instruments.
So this is how resonation works. Interesting enough, this same principle is needed for an excellent singing voice and is one of the main factors missing in most voices I audition.
Watch the video below as this person struggles to break a wine glass. Then I will introduce you to an easy step-by-step plan to break your first glass using only your voice.
Simplifying the Process
Let's get right to the nitty-gritty and go through the necessary steps for using the voice to break a glass.
Steps for Using Your Voice to Break a Glass.
- Select the right type of wine glass. Not any wine glass will do. (Some will argue this point.) Be sure you are using crystal, because it will resonate at the particular resonating frequency.
- To test this frequency, dip your finger in water then rub it gently around the rim of the glass. Your finger will actually vibrate on the rim of the glass and once you get the right frequency the glass will hum. You may want to do this a couple of times.
- Next, if you can match the pitch of your voice to the resonant frequency of the glass the vibrations in the air will strike the glass and it will begin to vibrate too. (This may take a couple of tries so don't give up.)
- You must sing with enough volume so that the glass will move as it vibrates further and faster than the material in the glass is able to move. (Added volume is absolutely necessary) With these conditions attained, the glass breaks. Make sure that you are close to the glass and protect your face with goggles.
The sound of your voice must administer hundreds of tiny pushes to everything around you. When you've done this, the energy of all the tiny pushes add up, add in the precise timing and the glass becomes stressed, eventually shattering. Hooray!
Singing the pitch an octave higher or lower will add more frequency, thereby breaking the glass. Use caution when attempting to break a glass. This experiment is for adults only. Never allow a child to try this (even though the video above is with a child). Notice how close the boy's mouth is to the glass.
A Few Tips and a Review
- Warm up your voice just before attempting to break the glass. Fifteen minutes or so should do it. Warming up the voice has proven to be helpful in completing the process.
- You must be right on pitch for a relatively lengthy amount of time. You cannot be off at all.
- You absolutely must have enough volume to break the glass. Inhale a large amount of air.
- Wear safety glasses during this experiment. Avoid getting cut as the glass breaks.
- Sing an "ah" with the glass close to your mouth.
- If the glass isn't breaking, increase the volume and duration of your sound.
- If you're not sure that you are singing the correct sound or that the glass is vibrating, here's what you can do.
- Place a straw inside of the wine glass.
- Slide your pitch (singing) up and down until the straw begins to shake.
- This is the pitch you want.
Thanks for reading!
Are you up to trying to break a wine glass using only your voice?
Questions & Answers
© 2013 Audrey Hunt