Scientific pitch notation in the context of "Viola"

A soprano (Italian pronunciation: [soˈpraːno]) is a type of classical singing voice and has the highest vocal range of all voice types. The soprano's vocal range (using scientific pitch notation) is from approximately middle C (C₄) = 261 Hz to A₅ in choral music, or to soprano C (C₆) or higher in operatic music. In four-part chorale style harmony, the soprano takes the highest part, which often encompasses the melody. The soprano voice type is generally divided into the coloratura, soubrette, lyric, spinto, and dramatic soprano.

In music, a pitch class (p.c. or pc) is a set of all pitches that are a whole number of octaves apart; for example, the pitch class C consists of the Cs in all octaves. "The pitch class C stands for all possible Cs, in whatever octave position." Important to musical set theory, a pitch class is "all pitches related to each other by octave, enharmonic equivalence, or both." Thus, using scientific pitch notation, the pitch class "C" is the set

Although there is no formal upper or lower limit to this sequence, only a few of these pitches are audible to humans. Pitch class is important because human pitch-perception is periodic: pitches belonging to the same pitch class are perceived as having a similar quality or color, a property called "octave equivalence".

A clef (from French: clef 'key') is a musical symbol used to indicate which notes are represented by the lines and spaces on a musical staff. Placing a clef on a staff assigns a particular pitch to one of the five lines or four spaces, which defines the pitches on the remaining lines and spaces.

The three clef symbols used in modern music notation are the G-clef, F-clef, and C-clef. Placing these clefs on a line fixes a reference note to that line—an F-clef fixes the F below middle C, a C-clef fixes middle C, and a G-clef fixes the G above middle C. In modern music notation, the G-clef is most frequently seen as treble clef (placing G₄ on the second line of the staff), and the F-clef as bass clef (placing F₃ on the fourth line). The C-clef is mostly encountered as alto clef (placing middle C on the third line) or tenor clef (middle C on the fourth line). A clef may be placed on a space instead of a line, but this is rare.

The violoncello (/ˌvaɪələnˈtʃɛloʊ/ VY-ə-lən-CHEL-oh, Italian pronunciation: [vjolonˈtʃɛllo]), commonly abbreviated as cello (/ˈtʃɛloʊ/ CHEL-oh), is a medium-low pitched bowed (sometimes plucked and occasionally hit) string instrument of the violin family. Its four strings are usually tuned in perfect fifths: from low to high, C₂, G₂, D₃ and A₃. The viola's four strings are each an octave higher. Music for the cello is generally written in the bass clef; the tenor clef and treble clef are used for higher-range passages.

Played by a cellist or violoncellist, it enjoys a large solo repertoire with and without accompaniment, as well as numerous concerti. As a solo instrument, the cello uses its whole range, from bass to soprano, and in chamber music, such as string quartets and the orchestra's string section, it often plays the bass part, where it may be reinforced an octave lower by the double basses. Figured bass music of the Baroque era typically assumes a cello, viola da gamba or bassoon as part of the basso continuo group alongside chordal instruments such as organ, harpsichord, lute, or theorbo. Cellos are found in many other ensembles, from modern Chinese orchestras to cello rock bands.

A bass is a type of classical male singing voice and has the lowest vocal range of all voice types. According to The New Grove Dictionary of Opera, a bass is typically classified as having a vocal range extending from around the second E below middle C to the E above middle C (i.e., E₂–E₄). Its tessitura, or comfortable range, is normally defined by the outermost lines of the bass clef. Categories of bass voices vary according to national style and classification system.

Italians favour subdividing basses into the basso cantante (singing bass), basso buffo (comical bass), or the dramatic basso profondo (deep bass). The American system identifies the bass-baritone, comic bass, lyric bass, and dramatic bass.

A baritone is a type of classical male singing voice whose vocal range lies between the bass and the tenor voice-types. It is the most common male voice. The term originates from the Greek βαρύτονος (barýtonos), meaning "low sounding". Composers typically write music for this voice in the range from the second F below middle C to the F above middle C (i.e. F₂–F₄) in choral music, and from the second G below middle C to the G above middle C (G₂ to G₄) in operatic music, but the range can extend at either end. Subtypes of baritone include the baryton-Martin baritone (light baritone), lyric baritone, Kavalierbariton, Verdi baritone, dramatic baritone, baryton-noble baritone, and the bass-baritone.