The Three Types of Resonance That Singers Need to Know
1) Sounding Board Resonance
This type of resonance is one of the easiest of the three to actually see its benefits, especially as it applies to singing. When touched to an object with a hard surface, the overall volume of the tone increases as well as the fullness of the tone itself. So what causes this? When I strike the tuning fork and touch it to a wood surface, the vibrations of the fork are transferred into the wood causing it to vibrate as well. Remember, the tuning fork is vibrating at 440 times a second and when I place the ball end on direct contact with the wood, the vibrating energy of the tuning fork causes the wood itself the vibrate 440 times a second as well. Now, I have two things vibrating together at the same time. That is why the tuning fork seems louder. The downside is that the tuning fork will vibrate for a shorter period of time.
We can see this type of energy transference simply by striking a table at one end while touching the table somewhere else. You can feel the energy leave your hand and travel through the table and the felt by the other hand. This is known as kinetic energy in the world science. This type of energy is all around us and is actually controlled in the practice of martial arts. The Chinese system of Kung Fu, for instance, calls this type of energy “chi” and it is this concept that gives good Kung Fu fighters incredible punching power. They literally inject their chi into an opponent causing the internal organs to feel the strike more so than the surface. This control is how the practitioners of this art can break boards or bricks without damage to their hand.
Within the art of singing, the sounding board resonance is actually the bones of our face and the bones inside of our mouths being set into vibration. The vibration of bone structures is the very reason we have terms such as head voice and chest voice. During the early days of modern voice training it was believed that our lower voice caused the chest to vibrate, and the higher (more soprano) voice caused vibration in what they called the mask, which is the front top of the face and lower forehead. These were referred to as the ‘head’ and ‘chest’ voices.
Let’s get you to feel sounding board resonance in action. If you place your hand across your chest and sing as low as you can in a moderate volume you can actually feel the chest vibrate. This is the idea behind the term, chest voice. Is this sounding board resonance in action? Absolutely! But, is this what gives our singing voices the rich full tone that the average voice teacher suggests? The answer is quite simply, no. You see, it has been proven through audio analyzing instrumentation over the course of the last few decades, and should have been put to rest ever since the 1970’s, that the bones of the chest do not add any audible resonance to the singer’s tone. This is due to a simple fact that the chest is covered by to much fat, muscle and tissue and is dampened before it ever adds additional resonance. Therefore, the whole notion of chest voice, which was actually a range classification in the classical era, is simply false.
The upper range classification used in the classical world known as “head voice” is also misunderstood. What was believed long ago, and is still taught today, is the theory that when we sing high notes, particularly in the soprano range, the upper part of the facial bones would be set into vibration and in turn add resonance to the voice. The fact is that the head does not vibrate only for the high voice. It vibrates no matter what pitch is sung. So to call the high soprano voice “head voice” and the lower voice range “chest voice” is one of the most inaccurate terms used among teachers of voice. Unfortunately, these terms are still used regularly among singers. We can use the terms, just not the normal explanations behind them. For us as contemporary singers the area that is most effected by sounding board resonance is without a doubt the inside of the mouth. There are plenty of hard surfaces such as the roof of the mouth that act perfectly as resonators.
2) Air Column Resonance
The second type of resonance that we are going to look at, called air column resonance, has a very interesting application in singing. It is where we get our vowel sounds. Air molecules themselves can be set into vibration just like hard surfaces can. But, air has the unique ability to be shaped. This is exactly what vowel sounds are. They are shaped forms of air set into vibration. The importance of this phenomenon is clear when we realize that when we sing, we are indeed singing vowel sounds. We cannot sing most consonants, we cannot sing ‘t’ for instance. We also cannot sing ‘s’. The consonants that can be somewhat sung, such as ‘r’ and ‘l’, often sound terrible. In other words, when we sing, we are singing vowels and vowels are simply shaped air forms that are set into vibration. You can see this for yourself simply by singing the sounds, ‘e’, ‘ah’ and ‘oo’. Notice that your mouth is shaping the air. This is why correct mouth and throat openings are so very important in singing. Not only do they affect the sound, but the more closed we keep these two the less air there is to set into vibration, which affects the volume. Almost anytime you see a picture of a well respected singer in the process of singing, you will find they almost always have there mouths wide open. Never shut. The same again is true of the throat itself. In fact, openness is an overall concept in singing and is particularly important when one is developing their vocal tone.
Reverberation may be one of the most well known forms of resonance as far as singers are concerned. It is so common in fact that most PA systems come with a tone thickening effect called reverb, which is short for reverberation. Almost everyone who has reverb applied to their voice has felt like they were singing in the bathroom or large hall. These are the types of areas where we sound like truly gifted singers. Why is this? Why do so many people sing in the shower for instance? I remember as a child watching an episode of the Flintstones where Fred overhears Barney singing beautifully while in the shower. It occurs to him that the two of them could make millions of dollars with Barneys magnificent voice. Unfortunately, the only place Barney could sing so beautifully was in the shower. Whenever he tried singing outside of the shower the million dollar voice was gone!
So the question I pose for you is this: Why showers? Why large rooms? Why bathrooms? Why do these types of environments almost always seem to make us sound better? The answer is, of course, resonance, which you will remember is defined as sound overlapping itself. And that’s exactly what a bathroom provides. You see, the average bathroom has walls that are almost always covered with ceramic tiles, which are extremely hard and dense. This hardness of the tiles actually makes sound waves bounce off of them, rather than absorb the sound, as would be found with less dense materials such as carpets and foam. The sound bounces, or is ‘reflected’ from wall to wall. So, you are not hearing your voice once…you are hearing your voice thousands of times, as it layers over itself. Imagine thousands of you signing together how thick the overall tone would be. All it took were two elements: Hard walls and space. The more space that is available, the more reverberation will occur. Again, note the effect of ‘openness’.
This type of resonance as it is applied to singing is achieved primarily in the mouth and back of the throat. Inside our mouths we have a hard dense ceiling commonly called the roof of the mouth, like the ceiling of a bathroom. The teeth are as close to tiles as you can get, which represents the walls of our bathroom. The back of the throat is the entrance into the sinuses which are very boney and covered in a thin membrane. Finally, below that is the larynx itself, which is made up of stiff cartridge. This central point between these two areas is known as the naso-pharynx and the entire structure itself can be looked at as our own personal facial bathroom. One can see that a more spacious mouth opening would help our tone by increasing the size of our facial bathroom, and therefore…increasing reverberation.
What is very interesting is that the roof of the mouth or, “hard pallet” is dense enough to make some sound frequencies bounce (particularity in the bass end of the tone) but is just soft enough to absorb other frequencies such as found in the treble side of tone and vibrate along with it. It is a perfect resonating chamber!
To sum up, in order to achieve the most important feature of singing, which is the tone itself, we must gain control over the amount and consistency of our vocal resonance. We saw that within voice there are three types of resonance that are available to us. These are 1) Sounding Board Resonance, 2) Air Column Resonance, and 3) Reverberation. All three are naturally occurring and all three can be controlled.