The human voice is the oldest musical instrument, predating the invention of any tool or string. Before the first stone was chiseled into a flute or the first skin stretched over a drum, early humans were already using their vocal cords to create patterns of sound that could be recognized as music. This primal act of singing was not merely a form of entertainment but a vital tool for survival, communication, and social bonding. The definition of singing varies across sources, yet its core remains the act of creating musical sounds with the voice, a process that has remained unchanged for millennia. Some sources define it as the utterance of words or sounds in tuneful succession, while others describe it as the production of musical tones by means of the human voice. Regardless of the definition, the voice has always been the primary vehicle for human musical expression, serving as the foundation upon which all other musical traditions were built. The ability to produce these sounds relies on a complex interplay of the lungs, larynx, and vocal cords, which function together to create a unique sound for every individual. The shape and size of an individual's vocal cords, combined with the size and shape of their body, ensure that no two singing voices are ever exactly the same. This biological uniqueness has allowed singers throughout history to develop distinct styles and identities, making the voice a powerful tool for personal and cultural expression.
The Science of Sound
The physical mechanism behind singing is a marvel of biological engineering, involving a precise coordination of multiple body systems. When a person sings, air is inhaled with the diaphragm and exhaled with the aid of abdominal, internal intercostal, and lower pelvic muscles. The pitch is altered with the vocal cords, which can loosen, tighten, or change their thickness to produce different tones. The sound resonates within different parts of the body, including the chest, head cavities, and the skeleton, which act as an amplifier similar to the tube in a wind instrument. The tongue, together with the palate, teeth, and lips, articulates and imposes consonants and vowels on the amplified sound. This process is known as vocal resonation, and it is the result of the basic product of phonation being enhanced in timbre or intensity by the air-filled cavities through which it passes. The primary method for singers to accomplish this is through the use of the singer's formant, which has been shown to match particularly well to the most sensitive part of the ear's frequency range. A more powerful voice may be achieved with a fatter and fluid-like vocal fold mucosa, as the more pliable the mucosa, the more efficient the transfer of energy from the airflow to the vocal folds. This scientific understanding of singing has evolved over the past two hundred years, with vocal pedagogists redefining or even abandoning older terms like chest voice and head voice in favor of more accurate descriptions of laryngeal function.
In European classical music and opera, voices are treated like musical instruments, and composers must have a deep understanding of the skills, talents, and vocal properties of singers. Voice classification is the process by which human singing voices are evaluated and designated into voice types, with qualities including vocal range, vocal weight, vocal tessitura, vocal timbre, and vocal transition points such as breaks and lifts within the voice. There are currently several different systems in use within classical music, including the German Fach system and the choral music system, though no system is universally applied or accepted. Most classical music systems acknowledge seven different major voice categories. Women are typically divided into three groups: soprano, mezzo-soprano, and contralto. Men are usually divided into four groups: countertenor, tenor, baritone, and bass. With regard to voices of pre-pubescent children, an eighth term, treble, can be applied. Within each of these major categories, several sub-categories identify specific vocal qualities like coloratura facility and vocal weight to differentiate between voices. Within choral music, singers' voices are divided solely on the basis of vocal range, with parts divided into high and low voices within each sex, known as SATB, or soprano, alto, tenor, and bass. This system often leads to misclassification, as most people have medium voices and must be assigned to a part that is either too high or too low for them. The science behind voice classification has been slow in adapting to more modern forms of singing, and attempts to adopt classical voice type terms to other forms of singing have been met with controversy.
The Art of Technique
Singing is a skill that requires highly developed muscle reflexes, and it does not require much muscle strength but it does require a high degree of muscle coordination. Individuals can develop their voices further through the careful and systematic practice of both songs and vocal exercises. Vocal exercises have several purposes, including warming up the voice, extending the vocal range, lining up the voice horizontally and vertically, and acquiring vocal techniques such as legato, staccato, control of dynamics, rapid figurations, learning to sing wide intervals comfortably, singing trills, singing melismas, and correcting vocal faults. Learning to sing is an activity that benefits from the involvement of an instructor, as a singer does not hear the same sounds inside their head that others hear outside. Having a guide who can tell a student what kinds of sounds he or she is producing guides a singer to understand which of the internal sounds correspond to the desired sounds required by the style of singing the student aims to re-create. The singing process functions best when certain physical conditions of the body are put in place, and good posture allows the breathing mechanism to fulfill its basic function efficiently without any undue expenditure of energy. Good posture also makes it easier to initiate phonation and to tune the resonators as proper alignment prevents unnecessary tension in the body. Habitual good posture also ultimately improves the overall health of the body by enabling better blood circulation and preventing fatigue and stress on the body. The ability to move air in and out of the body freely and to obtain the needed quantity of air can be seriously affected by the posture of the various parts of the breathing mechanism.
Modern Voices
In contemporary forms of music, sometimes referred to as contemporary commercial music, singers are classified by the style of music they sing, such as jazz, pop, blues, soul, country, folk, and rock styles. There is currently no authoritative voice classification system within non-classical music, and attempts to adopt classical voice type terms to other forms of singing have been met with controversy. The development of voice categorizations was made with the understanding that the singer would be using classical vocal technique within a specified range using unamplified vocal production. Since contemporary musicians use different vocal techniques and microphones and are not forced to fit into a specific vocal role, applying such terms as soprano, tenor, baritone, etc. can be misleading or even inaccurate. The use of the microphone has had several impacts on popular music, facilitating the development of intimate, expressive singing styles such as crooning, which would not have enough projection and volume if done without a microphone. Pop singers who use microphones can do a range of other vocal styles that would not project without amplification, such as making whispering sounds, humming, and mixing half-sung and sung tones. In the 2000s, controversy arose over the widespread use of electronic Auto-Tune pitch correction devices with recorded and live popular music vocals. Controversy has also arisen due to cases where pop singers have been found to be lip-syncing to a pre-recorded recording of their vocal performance, or, in the case of the controversial act Milli Vanilli, lip-syncing to tracks recorded by other uncredited singers.
The Voice in Society
The salaries and working conditions for vocalists vary greatly, and while jobs in other music fields such as music education and choir conductors tend to be based on full-time, salaried positions, singing jobs tend to be based on contracts for individual shows or performances, or for a sequence of shows. Aspiring singers and vocalists must have musical skills, an excellent voice, the ability to work with people, and a sense of showmanship and drama. Professional singers continue to seek out vocal coaching to hone their skills, extend their range, and learn new styles. Some singers learn other music-related jobs, such as composing, music producing, and songwriting. Singers market themselves to buyers of vocal talent by doing auditions in front of a music director. Depending on the style of vocal music that a person has trained in, the talent buyers that they seek out may be record companies, A&R representatives, music directors, choir directors, nightclub managers, or concert promoters. A CD or DVD with excerpts of vocal performances is used to demonstrate a singer's skills. Some singers hire an agent or manager to help them to seek out paid engagements and other performance opportunities, with the agent or manager often paid by receiving a percentage of the fees that the singer gets from performing onstage. Since the 1990s, televised singing competitions such as Sa Re Ga Ma Pa in India, American Idol in the US, and The Voice in the international franchise have become popular formats for discovering and promoting vocal talent. American Idol was launched in 2002, and the first singing reality show was Sa Re Ga Ma Pa launched by Zee TV in 1995.
The Brain and the Song
Much research has been done recently on the link between music and language, especially singing, and it is becoming increasingly clear that these two processes are very much alike, and yet also different. Levitin describes how, beginning with the eardrum, sound waves are translated into pitch, or a tonotopic map, and then shortly thereafter speech and music probably diverge into separate processing circuits. There is evidence that neural circuits used for music and language may start out in infants undifferentiated. There are several areas of the brain that are used for both language and music, such as Brodmann area 47, which has been implicated in the processing of syntax in oral and sign languages, as well as musical syntax and semantic aspects of language. Singing has been shown to help stroke victims recover speech. According to neurologist Gottfried Schlaug, there is a corresponding area to that of speech, which resides in the left hemisphere, on the right side of the brain. This is casually known as the singing center. By teaching stroke victims to sing their words, this can help train this area of the brain for speech. In support of this theory, Levitin asserts that regional specificity, such as that for speech, may be temporary, as the processing centers for important mental functions actually move to other regions after trauma or brain damage. Thus in the right hemisphere of the brain, the singing center may be retrained to help produce speech. Every spoken language, natural or non-natural language, has its own intrinsic musicality which affects singing by means of pitch, phrasing, and accent.
Global Traditions
All musical cultures have some form of vocal music, and there are many long-standing singing traditions throughout the world's cultures. Vocal music is probably the oldest form of music since it does not require any instrument or equipment besides the voice. Music which employs singing but does not feature it prominently is generally considered instrumental music. For example, some blues rock songs may have a short, simple call-and-response chorus, but the emphasis in the song is on the instrumental melodies and improvisation. Vocal music typically features sung words called lyrics, although there are notable examples of vocal music that are performed using non-linguistic syllables or noises, sometimes as musical onomatopoeia. In many modern pop musical groups, a lead singer performs the primary vocals or melody of a song, as opposed to a backing singer who sings backup vocals or the harmony of a song. An exception is five-part gospel a cappella music, where the lead is the highest of the five voices and sings a descant and not the melody. Some artists may sing both the lead and backing vocals on audio recordings by overlapping recorded vocal tracks. In many rock and metal bands, the musicians doing backup vocals also play instruments, such as rhythm guitar, electric bass, or drums. In Latin or Afro-Cuban groups, backup singers may play percussion instruments or shakers while singing. In some pop and hip hop groups and in musical theater, the backup singers may be required to perform elaborately choreographed dance routines while they sing through headset microphones. In Iran, women are not allowed to sing, highlighting the legal and cultural restrictions that can exist around vocal expression.