Basset clarinet

The basset clarinet is a clarinet similar to the usual soprano clarinet but longer and with additional keys to enable playing several additional lower notes. Typically a basset clarinet has keywork going to a low (written) C, as opposed to the standard clarinet's E or E♭ (both written), and is most commonly a transposing instrument in A, although basset clarinets in C and B♭ also exist, and Stephen Fox makes a "G basset clarinet/basset horn". The similarly named basset horn is also a clarinet with extended lower range, but is in a lower pitch (typically F); the basset horn predates, and undoubtedly inspired, the basset clarinet.

The basset clarinet was most notably associated with the clarinet virtuoso Anton Stadler (1753–1812), a contemporary and good friend of Mozart. Mozart wrote his Clarinet Quintet in A major, K.581 and Clarinet Concerto in A Major, K.622 for this instrument; the concerto is partly based on an earlier fragment of a Concerto for Basset Horn in G, K.584b. There is an aria in Act I of Mozart's last opera, La clemenza di Tito, (the mezzo-soprano Sesto sings Parto, ma tu ben mio) which features a basset clarinet obbligato.

As noted above, a basset clarinet is an A clarinet with an extension of a major third down. It is in fact related to the basset horn in F or G. Because Mozart's clarinet concerto is so important, the basset clarinet is quite an interesting instrument in spite of its small applicability. For the concerto the extension must be chromatic and the shape of the Viennese basset horn is not suitable for this. It has long been unclear how this instrument might have looked.

In a library in Riga in 1992 programmes were found of concerts which Anton Stadler played there in 1784. Two of those programmes show an engraving of Stadler's instrument.

Franz Xaver Süßmayr also wrote a concerto movement for basset clarinet.

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