This passage is taken from Voice and the Actor (pp. 46-47), by renowned voice teacher, the late, great Cicely Berry.
A consonant is a sound in which the passage of air or sound is stopped or partially stopped by either the lips or parts of the tongue. For some consonants the soft palate is involved, and the position of the jaw is always important. When the passage of sound is completely stopped it is called a plosive, and when it is only partially stopped it is called a continuant. Take for example the lip consonants ‘p’ ‘b’ and ‘m’ – for ‘p’ and ‘b’ the lips are pressed together to stop the passage of sound for a fraction of time. They hold the sound for a moment, and it is not until the lips are released that the consonant is heard with its slight explosion of breath, as for ‘p’, or ‘b’. On the other hand, for the nasal consonant ‘m’ the lips are closed to stop the sound coming out through the mouth, the soft palate is lowered to allow it to be resonated and sent out through the nose. The passage is then only partially closed and so we call it a continuant consonant because it is possible to go on making it for an indefinite length of time. The jaw for these sounds is partially open.
As you can see consonants fall into two groups, plosive and continuant. There is also a further difference that you will have noticed and that is that they be either voiced or breathed (sometimes also referred to as unvoiced). If they are voiced it means that the vocal cords are approximated and vibrating. In the case of ‘b’ it is a voiced or vibrating sound that explodes out when the lips are released, whereas for the breathed sound of ‘p’ the vocal cords are not drawn together and so it is purely breath that is stopped and then released. However, it must be noted that with a plosive voiced sound such as ‘b’ there is a fractional amount of breath that escapes on release, and this is what gives the voiced sounds a certain edge and carrying power. Of course, ‘m’ is a voiced sound and is particularly useful, as are all the voiced continuants in that you can feel the vibration or friction on the lips as you hold it, which is of particular value in placing the tone. These are therefore two further groups – voiced and breathed consonants.
In timing, and this is very important, consonants have three parts – the coming together of the muscles, the holding and the release. Bearing these differences in mind we will look at the muscles involved in making the other consonants.
The tip of the tongue is mainly responsible for the consonants ‘r’, ‘d’, ‘n’ and ‘l’ although the whole tongue is involved. For the plosives ‘t’ and ‘d’ the tongue tip is pressed against the teeth ridge just behind the top teeth and the sides of the tongue are pressed up against the top gums, completely stopping the passage of sound for a fraction of time. There should be no escape of air for the time that you hold it, or the consonant will be messy. As you release the tongue tip the sound explodes out – ‘t’ on the breath and ‘d’ vocalised. However, ‘l’ is a voiced continuant sound, for though the tongue tip is pressed against the teeth ridge stopping the sound there, the sides of the tongue are lowered to allow it to escape and continue out through the mouth; the sound is not completed until the tip is released. The quality of ‘l’, as you will see later, varies according to its position in a word and this difference in quality is made by the position of the back of the tongue, whether it is high or low. For ‘n’ the tongue is pressed up all the way round, but the soft palate is lowered to allow the sound to be resonated and continue out through the nose. It is not completed until the tongue-tip is released. The jaw is partially open for these sounds.
For the consonants ‘k’, ‘g’ and ‘ng’ the back of the tongue is pressed against the top of the soft palate to stop the sound coming through the mouth. As we release the back of the tongue, we release the consonants ‘k ’and ‘g’, but for ‘ng’ the soft palate is lowered to allow it its nasal resonance, and to give it its continuant value. The jaw is fairly open for these sounds. The freedom of the soft palate for these sounds is particularly important for their quality; if it is tense and tight the sounds themselves will be squeezed and thin, but if the palate is free to come down to meet the back of the tongue the vibration is much greater and consequently the resonance is fuller.
‘S’ and ‘z’ are continuant consonants in which the passage of the sound is channelled down the centre of the tongue. The jaw is closed and the sound escapes through the spaces in between the teeth, the placing of the tip of the tongue being variable; ‘s’ is breathed and ‘z’ is voiced. It is exactly the right amount of friction between the breath or sound resulting from the pressure of the tongue and teeth that makes it precise. ‘sh’ and ‘ge’ (the soft ‘g’ as in the word ‘measure’) are again continuant, one breathed and one voiced, formed by the sides of the tongue pressed against the gum and the blade arched high to make the pressure between it and the roof of the mouth, so making friction. The jaw is almost closed, and the sound is given a particular resonance by the rounding of the lips. ‘tch’ and ‘dg’ are plosives and are, in fact, each a compression of two consonant sounds said at the same time – the breathed ‘t’ and ‘sh’ said as one sound and the voiced ‘d’ and ‘ge’ the same way. Again, the jaw is almost closed. ‘F’ breathed and ‘v’ voiced are made with the jaw partially open, the top teeth pressing lightly but firmly against the lower lip to make friction as the sound escapes. ‘Th’ is made with the jaw partially open, the tongue placed between the teeth which press on it just enough to make friction as the sound escapes. It can be voiced as in the word ‘this’ or breathed as in the word ‘thin’.