The cassette tape company Memorex seared the image of Ella Fitzgerald shattering a glass with her voice into many people's collective memory in a television commercial that ran in the 1980s. With the right tools, good pitch, and a strong voice (or an amplifier), you can do this at home.
With Amplification
- Put on Safety Goggles to protect your eyes when the glass shatters. Use ear protection to protect your ears.
- Plug your microphone into your amplifier.
- Turn on your microphone and turn the volume on your amplifier to a high level.
- Place a crystal glass (see Tips) right in front of the speaker of the amplifier.
- Tap the glass and listen carefully to the ringing sound. You can also moisten your finger and rub the tip along the rim until the glass hums. Make note of this pitch and use it as a starting point in the next step.
- Sing several different high notes into the microphone until you hit the right one for that specific glass, at which point the glass will shatter.
Without Amplification
- Put on safety goggles to protect your eyes when the glass shatters.
- Put your lips almost directly against the glass.
- Sing at the same pitch found to break the glass with the previous method, and sing powerfully - over 90 decibels if you're using inexpensive glass.
Tips
- The key is to replicate the frequency that's created when you lightly strike the glass, known as the "resonant frequency". The ringing is caused by the glass vibrating. If you sing at the same frequency, and you sing loudly enough, you can make the glass vibrate to the degree that the glass shatters.
- It's easier to do this with crystal than with other types of glass. The glass in windowpanes and cheap cups is "soft", vibrates poorly and doesn't have a nice sound to it, whereas crystal vibrates well, emits a clear tone when tapped, is stronger because of the added lead oxide, and enhances sound frequency with its shape.
- Every glass is different and has a unique breaking frequency. A pitch that works with one glass probably won't work with another.
- The TV show Mythbusters recommends your tune sliding slowly up or slowly down.
- Also demonstrated on Mythbusters, placing a straw in the glass will help you see that it is indeed vibrating, and will aid you in hitting the right pitch.
Warnings
- Breaking a glass with your voice without amplification is extremely difficult. In a Mythbusters' TV episode, professional vocal coach, Jaime Vendera was able to demonstrate the technique, but only after failing the first 19 times.
- Turning your amplifier up to max risks damaging the amp and your speakers, as well as your eardrums if you do not have them covered.
- Be careful to avoid flying glass.
Things You'll Need
- An amplifier
- A crystal glass
- A microphone to plug into the amplifier
- Protective goggles
- Ear Protection
