Twang, pros and cons

A little TWANG is used by many professional singers in all musical styles. It is used in pop, rock, gospel, opera and other classical styles. 
Twang is a vocal technique used by many singers and it has several benefits. 
But there are some downsides to it as well, especially for sopranos singing in a choir!
The twang sound occurs when you narrow the area in your throat at the level of your larynx.
You can narrow the so called 'aryepiglottic sphincter' with your epiglottis.
You can alter the position of the epiglottis. You do that many times a day, when you swallow. The epiglottis is a leaf-like peace of cartilage that can close down over the larynx when swallowing food or drinks. It prevents the food and/or liquids from entering the airway.
In this video you can see how the epiglottis closes when you swallow:


When you close the epiglottis while making sound, it will alter the sound. A little TWANG is used by many professional singers in all musical styles. It is used in pop, rock, gospel, opera and other classical styles. 
The singer in the video shows you the difference and explains what it sounds like:



Using some twang has several benefits. It helps you to close your vocal cords so you will have a more clear sound (less breathy sound). It also helps to sing in the higher range of your voice and it adds volume to your voice. Especially in opera and musical it is used to give the voice more resonance.
Some singers find it difficult to make the twang sound. It can help to laugh like a witch, 'miau' like a cat or 'quack ' like a duck. If you can make that sound, you close the epiglottis a little bit. 


This image is used by permission from The Vocalist Studio International
The left image above shows the larynx and within on the right the spoonlike epiglottis.The image on the right shows you the epiglottis in TWANG position.
If you have trouble making the TWANG sound or it doesn't feel right, you can start by consciously swallowing a couple of times. While swallowing try to feel the epiglottis closing.
After swallowing, try to maintain the swallowing position and try to breath in through your nose. In the beginning this can take a lot of effort! If you think you can maintain the swallowing position, try to make some sound. In the end you need to be able to make twang with an open throat, relaxed tongue and jaw, etc.
There are pros and cons about singing with twang.

Twang gives the voice more resonance and the ability to 'cut' through better but too much of it prevents the voice from blending in a choir.
Especially sopranos singing with too much twang can ruin the sound of a (classical) choir.

If you are a 'chainsaw' soprano with too much twang, try the following:

Before singing, swallow a couple of times. Each time you swallow you will feel your larynx being lifted. While doing that you can feel some muscles become active to lift the larynx. You can feel it somewhere behind your eyes, at the level of your ears. Now relax your tongue and jaw but maintain the active feeling in the head and start singing.
There are more ways to solve too much twang, you could try to think about breathing in while singing, or yawning a little bit.

Tilting the larynx will also help you to avoid too much twang.

Another thing is that using twang is NOT healthy for people suffering from nodules, polyps or other problems.
So be careful with it. 
The best way to experiment with twang is to start using it with nasality. Nasality lowers the airpressure and decreases the risk of vocal trauma.
A good voice teacher can help you with this technique.