If we were to create an equation for an individual’s unique voice, it might looks something like this:

Voice Quality = vocal tract configuration + laryngeal anatomy + learned component

The shape of an individual’s vocal tract is partly genetic, partly learned. Necks are long or short; pharynxes may be narrow or wide. While these attributes are genetically determined individuals may also manipulate vocal tract shape. Highly trained singers have many tricks to change the contours of their vocal tracts to improve the sound coming out of their mouths. Lip rounding lengthens the vocal tract, for example.

The length of one’s vocal folds is determined by genes. However, the general hydration of one’s vocal fold tissues or muscular agility of laryngeal muscles can be at least partly controlled by vocal health and training.

There are of course our own vocal habits. These would be items such as rhythm and rate of speech and vowel pronunciation. Rhythm, obviously, includes mannerisms such as periodic pauses to search for the right word, while rate refers to the speed of an individual’s syllables and speech.  A speaker’s habits also influence how much air pressure is used to produce sound and how s/he uses throat muscles to open and close the vocal folds.

So, should we be surprised that family members often sound alike? After all – for most of us – the home and the pool of our siblings, parents and children are shared.

How do we describe perceived vocal qualities?
The short answer: not very well. The average person easily recognizes familiar or famous voices, yet would have difficulty describing them in words. Language has not been as well developed for vocal characteristics as it has for appearance. People can be tall, bald or wrinkled, but how do we describe how they sound?

Despite their training, vocologists and voice researchers also disagree about exact descriptions of vocal qualities.

An esteemed academic used the following terms to describe different voices….. honky, wobble, yawn, twangy, breathy, strained, rough, resonant, pulsed, pressed, jitter, hoarse, flutter, aphonic, glottalised, covered, creaky, biphonic, diplophonic, incredible .. how do you think you sound ….??