# Key used by clarinet

I do not understand the key notation for the clarinet in an orchestral score I am looking at. This is an extract from the Andante of the Ravel concerto in G:

The clarinet has a different key signature than the rest, and though the score uses a treble clef, what the clarinet plays is actually a third below. Surely this has something to do with the fact that the score says "Clar. in la", i.e. something like "play an A when you see a C", but I am confused where that notation comes from and its exact purpose. Why not writing an A if an A needs to be played?

• I don't have the time to write a detailed answer but look up "transposing instrument". You will find plenty on the subject. Jun 3, 2018 at 6:40
• Related question - why have some instruments a note name added. Jun 4, 2018 at 12:24

The point of transposing instruments is to be able to play different sizes of the same instrument (such as an A and a B clarinet) without learning a new set of fingerings.

An A clarinet is slightly longer than a B clarinet, therefore whenever you use the same fingering to play a tone as on the B (or C) clarinet, the result sounds a second (or a third) lower. But it's much easier for players if they can rely on a particular written note, e.g. C, corresponding to the same fingering on both instruments rather than two different fingerings. Therefore, we notate the parts for A clarinet a third higher than for the C clarinet, and everything comes out just right.

This puts an additional burden on readers of the score, such as conductors, but they already need a lot more education for their job than just playing an instrument, and understanding transposing instruments is just a small part of that.

• Note (sic) that the 'B' clarinet in this answer refers to the German B, which sounds in pitch the same as our Bb. Here, in this score, the clarinet is an A clarinet, which needs its part written a m3 higher to match the pitch of the rest of the orchestra.
– Tim
Jun 3, 2018 at 7:01
• Small nitpicking. La is the name of the tone A ( C is called Do ). The A clarinett is slightly larger than the Bb clarinett. Jun 3, 2018 at 7:10
• @Lolo, the musicians I know who have perfect pitch find it difficult to play transposing instruments because they do hear a different pitch than the one they are reading. However, those without perfect pitch usually don't have a problem reading the transposed part. The discrepancy between the written music and the actual pitch doesn't affect them. Jun 3, 2018 at 10:55
• @HeatherS. - a friend of mine, a great early music performer with perfect pitch, had difficulty singing transposed parts, until she simply (!) learned how to read all seven possible clefs. Now she just thinks the appropriate clef and key signature and is singing the written pitches. Jun 3, 2018 at 13:21
• The stories are abound of first clarinet players by mistake taking the wrong clarinet for an important solo in the classical literature, and transposing a half step up or down on the fly. Only shows that great musicians are great musicians (which should not be a surprise). Jun 4, 2018 at 10:53