The human voice is a complex instrument. Humans have vocal cords which can loosen or tighten or change their thickness and over which breath can be transferred at varying pressures. The shape of chest and neck, the position of the tongue, and the tightness of otherwise unrelated muscles can be altered. Any one of these actions results in a change in pitch, volume, timbre, or tone of the sound produced.

One important categorisation which can be applied to the sounds singers make relates to the register; or the "voice" which we use. Singers refer to these registers according to the part of the body in which the sound most generally resonates, and which have correspondingly different tonal qualities. There are widely differing opinions and theories about what a register is, how they are produced and how many there are. The following definitions refer to the different ranges of the voice.

What is Placement?
Placement is the term used to describe the technique of being guided by the vibrations and resonances of the body when singing. These sensations can usually be felt in the chest, face, nose, mouth etc.,

What is Register?
Like most things singing related, peoples opinions and descriptive terms differ on this subject, but generally speaking the word 'register' is used to describe a section of the voice. These 'sections' are loosely catagorised by how cords vibrate, glottal and pharyngeal shape, where the voice resonates in the body and the resulting quality or timbre of the voice.

What is a Register Break?
This is an area of the voice which is situated between one register and another, when the voice breaks or drops a note consistently in the same area, it is usually considered to be a transition point or Passaggio between one register and another, i.e., from a heavy voice to a light voice.

What is Vocal Fry?
Glottal or Vocal Fry is the term used by some to describe lowest part of the voice. It is effectively a toneless "rattle", rasp or roughness produced by the vocal cords at the lower end of the range which is often used as an effect in rock singing. Click Here for an audio example of spoken glottal fry at Lions Voice Clinic website.

What is Chest Voice or Chest Register
Usually a deep or rich full sound that is most commonly used during speech. Air flows over the vocal folds which are are fully apart and the vibration or resonance can often be felt in the upper chest. This is the area of the voice where you should be singing the lower notes of your range.

What is Middle Voice or Middle Register?
The term Middle Voice is not as commonly used as some of the other descriptions like chest and head voice. This section of the voice may also be referred to as mix or blend and it describes an area where a vocal bridge or passaggio may occur. Once the singer has mastered the art of moving smoothly through this transition area it is considered to be mixed or blended.

What is Head Voice or Upper Register?
Remember those lengthening cords as you ascend the range? Well you'll need these to access 'Head Voice' which is where you should be singing those high notes. The resonance is usually felt in the cheekbone, teeth/lips area which is sometimes referred to as the mask or masque.

What is Whistle Voice or SuperHead?
This is the top end of the vocal range which sounds similar to a whistle or squeal. Few singers use the whistle register although it has gained popularity amongst some female commercial artists.

What is Falsetto or False Voice?
Falsetto is the lightest register and requires loose vocal cords and incomplete closure which produces a breathy voice that can sound quite feminine although it is generally used by men rather than women.
Read more about Falsetto.

How do you know if your singing in Head or Chest Voice?
Place your fingers on your breast bone and then sing a few notes from the bottom end of your range, you should be able to feel the vibration in your chest through your fingers, if you don't feel anything try belting 'Hello' - if your singing in chest voice you should feel something there. If you are singing in your head voice, you should feel the vibrations somewhere in the region of your teeth/lips, cheekbones, nasal cavity, or forehead.

These are just a small example of the extensive links to online exercises and lessons we have available in the Singers Articles section, which contains complete listings of lessons, exercises or articles available on each site with direct links to the page (when not a framed site) plus answers to pretty much everything a beginner, intermediate, advanced singer or teacher needs to know! (All links open in a new window).

Baroque Tenor
Tako Oda's response and explaination of head voices and falsetto in Tenors.

David Stroud's Voice Studio
This site maintained by Speech Level Singing Tutor contains some excellent free videos showing the vocal folds in action plus a bundle of advice and tips for singers.

Falsetto Pedagogy vs SLS
A technically orientated and informative posting on head voice and falsetto at The Vocalist discussion group by Lloyd W. Hanson.

Dutch Diva's
Site provides pictures, biographies, sound files, reviews and discussion on Dutch opera / concert singers and conductors plus a few notable international performers. Of special interest is 'The High C' page containing information and sound clips, a full list of recognised voice types (with known artist examples) plus a good diagram of main ranges on the piano with typical note frequency stated below. Available in Dutch and English.

Good Rich Vocal
Listen to 36 audio examples of correct and incorrect singing. Hear the "mix," Chest voice, head voice and super head voice. Very clear explanations

Head & Chest Voice
Helpful response to query on the differences between head and chest voice posted to Tessitura Discussion Group by Kristina.

How to sing classical nonclassical jazz rock folk etc
An informative explanation of the basic oscillation patterns observed in phonated sound posted to The Vocalist discussion group by Lloyd W. Hanson

Joining Voices
Thread on voice registers and transitions at Tessitura Discussion Group.

Male Registers
A basic description of male registers posted to The Vocalist discussion group by Micheal Gordon.

Registers & Passaggio
Article by voice teacher Paul Mason contains explainitory definitions of vocal registers and passaggio.

source : Voice Registers Wikipedia & Vocalist