Clarinets other than the standard B♭ and A clarinets are sometimes known as harmony clarinets. However, there are many differently-pitched clarinet types, some of which are very rare. They may be grouped into sub-families, but grouping and terminology vary; the list below reflects popular usage and compares it with systems advocated by a few influential authors. See separate articles for additional details.
Piccolo clarinet — Very rare. Also known as octave clarinet or B♭ sopranino clarinet. Pitched an octave higher than the B♭ clarinet.
A♭ piccolo clarinet.
Rendall uses the term octave clarinet and includes also obsolete instruments in C, B♭, and G.
Shackleton lists also obsolete instruments in C, B♭, and A.
D clarinet — Rare in America and western Europe. Required in Molter's very early clarinet concertos.
Rendall lists the E♭ and D clarinets, along with obsolete instruments in G, F, and E, as sopranino clarinets.
Shackleton lists the E♭ and D clarinets, along with obsolete instruments in F, and E, as sopranino clarinets.
The E♭ and D clarinets are commonly called piccolo clarinets in eastern Europe and Russia.
C clarinet — Moderately rare. Clarinets in C are common in the scores of some composers' classical opera, in which clarinetists were expected to be equipped with instruments in A, B♭ and C. Also occurs in clarinet choirs, often as a substitute for the oboe.
A clarinet — Standard orchestral instrument used alongside the B♭ soprano.
G clarinet — Also called a "Turkish clarinet". Primarily used in certain ethnic music. This type of clarinet is rare.
Rendall lists the C, B♭, and A clarinets along with the obsolete instrument in B as sopranos, and the clarinette d'amour in A♭ and G and the clarinet in G as obsolete altos.
Shackleton lists the C, B♭, A, and G clarinets along with obsolete instruments in B and A♭ as sopranos, noting that the A♭ and G often occurred as clarinette d'amour in the mid-18th century.
Rice classifies G clarinets with flared bells as altos, with pear- or bulb-shaped bells as clarinets d'amour.
Basset clarinet — Essentially a soprano clarinet with a range extension to low C (written).
A basset clarinet — Most common type.
Basset clarinets in C, B♭, and G also exist.
Rendall includes no basset clarinets in his classifications. Shackleton has three in his collection: Numbers 5389 (B♭ and A set) and 5393 (in A). See Catalogue of the Sir Nicholas Shackleton Collection, Edinburgh University Collection.
Basset horn — Alto-to-tenor range instrument with (usually) a smaller bore than the alto clarinet, and a range extended to low (written) C.
F basset horn — Most common type.
Rendall lists basset horns in G (obsolete) and F as tenors.
Shackleton lists also basset horns in G and D from the 18th century.
Neither Rendall nor Shackleton lists A, E, or E♭ basset horns though these apparently existed in the eighteenth century.
Alto clarinet — Pitched a perfect fourth lower than the B♭ soprano clarinet.
E♭ alto clarinet — Most common type. Range usually down to low E♭ (written).
Rendall lists the E♭ alto and F tenor clarinets as tenors (along with the basset horns).
Shackleton lists F alto clarinet as obsolete.
Bass clarinet — An octave below the B♭ clarinet often with an extended low range.
B♭ bass clarinet — The standard bass.
A bass clarinet — Very rare.
C bass clarinet — Obsolete.
Rendall and Shackleton list C, B♭, and A; Rendall lists only C as obsolete, while Shackleton calls A "rare". Rendall groups these in baritone and bass.