What is the difference between the B flat and A clarinets?

There are a whole family of clarinets of various sizes.

The smallest is the Ab clarinet. It’s so small, in fact, that many players cannot even play it because their fingers are bigger than the keys and the tone holes.

The Eb clarinet is about half the size of a Bb clarinet and is used for color in both band and orchestra.

What is the difference between the B flat and A clarinets? The Bb clarinet is the main clarinet, used in both bands and orchestras. The A clarinet is a slightly longer clarinet with a darker tone and half-step deeper pitch, used almost exclusively as an orchestral and solo instrument.

After that, there are the alto, contra-alto, bass, and contrabass clarinets. There is also a very rare sub-contrabass clarinet that plays an octave lower than the contrabass.

C clarinets were once common, but the intonation problems caused by a cylindrical bore covered at one end by a single reed when that bore is tuned in concert pitch made them untenable.

Even today, when the manufacturing techniques are much better than previously, they are little more than an affectation because professional players who are confronted with C clarinet parts simply transpose up a whole step while using the Bb clarinet.

All of them have the same key and hole pattern. The larger ones have keys over the holes, though, because a person’s fingers are not large enough to cover the holes.

Of all of these instruments, the two most commonly used are the Bb clarinet and the A clarinet.

The A clarinet is nearly exclusively an orchestral and solo instrument. It’s almost never found in bands.

The A clarinet sounds a half-step lower than the Bb clarinet. These instruments take their names from the concert pitch note that is produced when the player plays a C. Orchestral musicians will have one of each clarinet that they use.

Composers choose either the Bb or A clarinet for the parts in their works.

A lot of the time, the players will have to change back and forth from one clarinet to the other as required by the composer.

The reasons behind these changes are twofold: First, the composer might want the darker timbre of the A clarinet for effects’ sake. Second, the composer might choose the A clarinet to make the part easier on the player.

Here’s how that works.

Because the clarinet is a Bb instrument, it sounds a whole step lower than the written notes it plays. For example, when the clarinetist plays a C, the instrument sounds a Bb. That’s why it’s called a Bb clarinet. That means that the clarinetist must play written Bb parts in a key a whole step higher than the written music. If a piece is in F major, then the clarinetist will have to play in G major. That’s not usually a big deal.

If, however, the piece is composed in E major, then the clarinetist will have to play in F# major, a key with six sharps in it.

Now, for a professional player, the key of F# major sits well on the clarinet. It is not a left hand-intensive key like C# major, but it is still much more difficult than playing in a key with fewer sharps. That’s where the A clarinet comes in.

The A clarinet sounds a minor third lower than the written pitch. When the player plays C, the clarinet sounds an A. So, if we take the same piece in E major as before, the written part would have to be minor third higher than E major. In this case, that’s G major, which is a key that has only one sharp.

In intense technical passages, playing in one sharp is much better than playing in six sharps. Sure, a pro will handle the six sharps, but a lot of the time “back in the day,” nonprofessional players would sit in during performances when the lead person was either ill or otherwise indisposed. Also, it was common practice at that time to perform without rehearsal. Even a pro would have a tough time with a piece in six sharps while sight reading.

Sometimes, however, composers won’t give clarinetists a break because the technique on the A clarinet would be more difficult than it would on the Bb. This is often the case when the part is in the altissimo register, which consists of the very high notes above the staff. Altissimo clarinet fingerings are largely a point of view, much the same as early translators thought when they worked with Sun Tzu’s “The Art of War.”

The player has to perform lots of cross fingerings. That’s where some fingers go up from the keys and holes while others are going down onto the keys and holes. Some of these notes are also better in tune than others.

One example of using the Bb clarinet instead of the A clarinet, despite the clarinetist having to play in four sharps, is the lyrical solo from Aaron Copland’s “An Outdoor Overture.” The octave jump between the second-top space E and the octave above is much better in tune and stable than it would be going from a top-line F to the octave above. This is particularly true using an alternate fingering for the to high E.

Besides simply for tone color, another reason to use the A clarinet rather than the Bb clarinet even if the key isn’t overly tough on the Bb clarinet is if the music calls for a low concert C#. The lowest note on the Bb clarinet is a concert D. So, if a C# is required, then the player must use the A clarinet for that passage.

The tone color aspect must not be underestimated.

Ferdi Grofe composed the clarinet part for “Sunrise” in the six sharps of F# major. It is a very bright key on clarinet, and that brightness evokes the sunrise.

Beethoven uses the same philosophy in the Symphony No. 6 during the fourth movement, The Thunderstorm, only there it’s to show shafts of light burning through the clouds shortly before the end of the storm.

Here’s a video that explains a lot of what you find in this article:

The Curious Cases of Bass Clarinet in A

A few composers, notably Sergei Rachmaninoff, write parts for bass clarinet in A. Mischievously, they also write these parts in bass clef!

Bass clarinets pitched in A are even rarer than Ab sopranino clarinets. So, the poor player not only has to transpose the parts down a half-step, essentially adding a flat to everything, but the person also has to convert bass clef into treble clef.

Other composers who write bass clarinet parts in A using bass clef include R. Strauss, Stravinsky, and the Australian composer Maria Glenfell.

More confusing, there are different “schools” of playing bass clarinet in A. Russian, German, and Italian methods transpose differently. Each has its advantages and disadvantages. In most cases, the part is written so as to minimize the use of leger lines.

French bass clarinet music, for example, never uses bass clef and sometimes has four or five leger lines written below or above the staff. Mahler, interestingly enough, as an Austrian-Bohemian composer, uses French bass clarinet notation throughout his catalog of works.


The Bb and A clarinets, along with the Bb bass clarinet, who is pulling hair out with sometimes freaky transpositions, are mainstays of the orchestra.

Composers use them in different ways and for different reasons.

Clarinetists should become familiar with them all because they might be called upon at any time to play any of them.

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