We will answer this question from the physiological perspective.
When we sing, our body employs a lot of body parts to produce the sound. One of the main organs involved in both singing and speaking is the larynx. The human larynx (and surrounding body parts linked to it) can be positioned in 4 distinctive ways. Each of these positions will make your voice sound in a distinctive way too. These positions (or configurations) are called Laryngeal Mechanisms.
They are identified with numbers: M0, M1, M2, M3 (M stands for the Mechanism).
M0 is responsible for generating the lowest sounds, M1 higher than M0, M2 higher than M1, and M3 for the highest ones. Some sound references:
- M0 – Snoring
- M1 – Regular speech
- M2 – An ‘owl’ sound or the way Mikky Mouse talks
- M3 – Whistles
The table below shows how popular terms used to identify the registers relate to the mechanisms:
| Mechanism M0 | Mechanism M1 | Mechanism M2 | Mechanism M3 | ||
| Fry Pulse Strohbass Voix de Contrebasse | Modal Normal Chest Heavy Thick Voix mixte (M) Mixed (M) Voce finta (M) Head operatic (M) | Falsetto Head (W) Loft Light Thin Voix mixte (W) Mixed (W) | Whistle Flageolet Flute Sifflet |