Reading Early Clarinet History Through the Instruments Themselves

Learning from the instruments themselves

Most discussions of the early clarinet’s history rely on theoretical writings, which often leads to the same traditional narrative being repeated. This article takes a different approach: it is grounded in direct experience with early clarinets — measuring them, building reproductions, and, most importantly, playing them.

The J.C. Denner chalumeau

One of the earliest surviving instruments is the J.C. Denner chalumeau, housed in the Bavarian National Museum in Munich. Its bell resembles a recorder’s, with two keys placed opposite each other (and apparently no speaker pipe). The bore measures a remarkably wide 15mm, while the tone holes average only 5mm in diameter. This instrument may represent an early experiment by the Denner workshop, because it does not function well: the tone is muffled and restricted. The likely causes are the oversized bore, the undersized tone holes, and the absence of a proper flared bell. As it currently stands, the instrument would not have been very successful, though it was probably something of a novelty.

It is, of course, possible that the bore was enlarged at a later date — a practice sometimes found on clarinets: as pitch standards rose, instruments were sometimes reamed out to sharpen them. Interestingly, this chalumeau can play in the clarinet register when the back key is open. If that was an intentional design feature, it raises the question of whether this instrument should actually be called a clarinet rather than a chalumeau. Exactly what defines a chalumeau? The addition of a raised speaker key (with its tube reaching into the bore) may have simply been an improvement to prevent condensation from entering the bore.

Two other features of the J.C. Denner chalumeau deserve attention: the keys and the overall length. The keys are mounted on the mouthpiece joint, which is nearly as long as the body joint. The keys themselves are very long, requiring care when assembling the instrument because they protrude from the end. The total length seems odd at first — it is even shorter than the Denner D clarinet, which sounds a tone higher. The explanation is straightforward: there is no flared bell.

Who made the first real clarinet?

It is impossible to say with certainty who built the first authentic clarinet, with both a proper speaker key and a flared bell. Too few instruments and written records have survived. A puzzling clarinet resides at the University of California. Its middle joint appears to be stamped J.C.Denner, and the bell carries a third key — a feature that would not become common on other instruments for another fifty years. The mouthpiece joint is lost. Since the bell is unstamped (all other Denner clarinets are stamped on the bell), and since name stamps were often passed through generations, clear identification is difficult. The bell might be a later addition; a similar style of bell appears on clarinets made decades later (see the Zencker clarinet). Still, the fact that the upper two keys are not directly opposite each other, and that the instrument uses an improved speaker key, is noteworthy.

If the middle joint of that instrument is authentic, J.C. Denner may well have built the first clarinet with a correctly functioning speaker key. Even so, it does not prove that the enlarged bell appeared at the same time as that key.

Jacob Denner’s fine workmanship

What we can be sure of is that Jacob Denner (d. 1735) made superb clarinets. These are beautifully turned instruments, equipped with a speaker key, a front key, and a wide flared bell. Constructed in boxwood with brass keys, they have a large bore of about 14.7mm and fairly wide finger holes. The D clarinet consists of three joints: a combined short barrel and mouthpiece, a middle joint, and a bell that is nearly as long as the middle joint, incorporating the lowest finger hole. On the C clarinet, the middle joint separates into two sections.

The mouthpiece has no table: if you remove the reed, a large slot is revealed underneath. It is much larger than a modern mouthpiece, easily accommodating a soprano saxophone reed. The result is an extremely loud, flexible instrument whose clarinet register sounds like a trumpet. When the author played one in Bach’s B-minor Mass, audience members had no idea that baroque clarinets were being used instead of trumpets. It very likely that such instruments were sometimes substituted for trumpets in that sort of repertoire.

Two-key limitations and unexpected flexibility

On two-keyed clarinets, there is no key to produce a B between the two registers; all fingers down produces a written C. But obtaining this partial-register B is not a problem. The instrument’s flexibility means that the standard Bb fingering can be lipped upwards to reach the B. In fact, nearly every note can be bent about a semitone in either direction. Pitches on these Denner instruments lie between A-415 and A-420, and the clarinets are pitched in C and D.

The effective range in the low register is limited mostly to the scale of F, without a low E. In the clarinet register almost every note is available; the problematic ones are C#, Eb, and G# (going upwards). Music of the period tends to stay in the clarinet register; when it ventures into the low register, the writing is usually simple arpeggios.

Playing these instruments makes it clear that the embouchure was radically different from what modern players use. A soft reed and an extremely relaxed embouchure are essential. This approach helps to widen the naturally narrow twelfths and can facilitate playing with the reed on top.

The Zencker D clarinet (ca. 1740)

The Zencker D clarinet at the Nuremberg Museum marks the next step in development, dated to about 1740. Externally it closely resembles the Denner D, but the mouthpiece is much smaller — only 11mm across at the tip — and the bore is reduced to 13.5mm. The mouthpiece also has a table under the shorter reed. The result is a somewhat sweeter tone, lacking some of the earlier instrument’s trumpet-like flexibility, but capable of reaching high G. It probably dates from around Molter’s era and suits his concertos admirably. Mr. Snorrason of Iceland recorded the A-major concerto on a Zencker reproduction, producing a truly impressive (and clearly challenging) sound. The compass is the same as the Denner, though the middle B is more difficult because of the reduced flex; the high notes, on the other hand, come more easily with the smaller mouthpiece.

The third key appears

As clarinets became gradually less flexible, a third key on the bell section became necessary for producing a reliable B. One of the earliest such instruments belongs to R. Paur (or R. Baur) and is a C clarinet at the Nuremberg Museum, dated to about 1765. It again shows a very small mouthpiece and a bore of 13.8mm. The third key sits on the back of the bell, operated by the thumb. Although this positioning seems odd for operating a B key, it actually preserves the option to play the clarinet with either hand on the lower joint. This was evidently a common concern, because this very instrument also has two G/D holes (left little-finger and right little-finger), with one sealed by a wooden plug. Even with the third key, the clarinet remains ambidextrous.

Willems and the growing key count

Two clarinets by J. B. Willems at the Brussels Conservatoire Museum illustrate two distinct phases of design evolution. Willems worked in Brussels from roughly 1760 to 1800. The first is a four-key C clarinet resembling the Paur instrument; the fourth key sounds Ab/Eb, and the E/B key still uses the thumb. The second is a later A clarinet with five keys. Now the E/B key is operated by the little finger, and the lower part is split into two sections. For the first time, we see a separate bell joint without any keys. This instrument closely resembles a standard continental classical clarinet, except that the barrel and mouthpiece remain one piece. The tone is much sweeter and has completely shed the earlier clarinet’s trumpeting quality. Pitches now centre on Bb and C, with occasional A; D clarinets, once the most common, become rare.

Around 1800: five or six keys

By about 1800, clarinets carried five or six keys and had separate mouthpieces. This allowed mouthpieces to be made in a much harder, more stable wood — typically ebony. Mouthpieces grew a little larger, to about the size of a modern Eb clarinet mouthpiece. Name stamps often appear on the reed side, which suggests the reed was still generally placed on top.

English vs. continental mouthpiece traditions

English mouthpieces featured long tenons that passed completely through the barrel joint and abutted the tenon of the upper finger joint. This made them mostly interchangeable, which helped with replacements (mouthpieces on early clarinets are frequently broken or too short). Many mouthpieces are stamped “J. Wood,” who appears to have manufactured most mouthpieces for English makers. Their bores measured roughly 14.3mm on Bb instruments and 14.1mm on C. On the continent the situation differed greatly, with many different conical bore sizes. Continental mouthpieces had short tenons with a raised ring for holding the ligature cord. While usually a bit larger than the English pattern, continental mouthpieces were often much narrower at the tip, with a smaller slot.

Mouthpiece tips and reed choices

For all mouthpieces of this era, a tip opening of less than 1mm is best, combined with a fairly soft reed. If the tip opening is wider or the reed is too hard, the forked notes become very muffled and difficult to sound reliably.

Materials and construction

The bodies continued to be made of boxwood, with keys of brass (often sand castings). Springs were riveted onto the keys and made of brass, hardened by burnishing. The supporting rings around the sockets now used ivory, whereas they were once turned from the body-wood itself. Pitch had risen to around A-440. Most baroque-style ornamentation disappeared, leaving only the ivory rings with a hint of decorative turning.

Standard five- and six-key setups

The standard five-key classical clarinet operates the speaker, A, G#/Eb, F/C, and E/B keys (now controlled by the left-hand little finger). A sixth key appears very often: continental makers favoured a C#/G# key, while English builders preferred a long side key on the first joint to produce B and C over the break — a useful addition for rapid scale-wise motion crossing the break.

A persistent left-hand ergonomic challenge

On all these early instruments, the G#/Eb hole sits below the G/D hole. This is necessary so the right-hand little finger can cover the G/D hole, but in practice the Eb hole ends up enormous and usually flat, while the D hole is tiny and drilled obliquely downward into the bore. The problem was not resolved until Müller introduced an extra key for this note.

The classical system persists and evolves

This classical system basically continued into the 1830s, with changes limited to adding more keys onto the same structural framework — sometimes as many as thirteen. Even with that many keys, instruments rarely incorporate a thumb rest. An occasional German clarinet has a thumb rest, usually carved as part of the wooden body. Notably, the fundamental fingering patterns did not change; the extra keys were used only as needed to improve some forked notes.

A surprisingly large number of surviving instruments have had their additional keys removed and the holes plugged. This makes sense: the early keys were fairly primitive and unreliable, and extra keys could just get in the way. The author once owned a thirteen-key clarinet but sold it, preferring a six-key instrument. That helps explain why six-key instruments remained in production into the 1840s. The most useful keys to add beyond the five basics are C#/G#, B/F#, and Eb/Bb.

Key mounting, pads, and cups

Extra keys were typically mounted on additional turned blocks. By now, blocks were carved away flush with the body except where they were needed to support the keys. Some keys were mounted in brass saddles held to the body with small screws. Flat leather pads were used, and their seatings were flat as well. The “cups” were obviously also flat and, up until the 1820s, rectangular. Cubical round cups sometimes replaced them later — again, still flat. The keys were held in the blocks with simple brass pins driven through as pivots.

Where this history ends

This brief account takes the early clarinet’s development as far as major expansions in key-work; after this point the first Boehm clarinets appear in the 1850s. This extremely rapid progress in the space of a few decades became possible only with more reliable key-work technologies: rods and point screws, pillars, modern pad and cup types, and stronger materials.

Playing the early clarinet: practical advice

A beginner approached with a modern Boehm mind-set will struggle. You must understand that these instruments require time to learn. A soft reed makes a fundamental difference; without it, the forked notes will not speak clearly. Expect to alter reeds: on early clarinets they usually need shortening at the stub end, and scraping is often required. Cross-fingerings present a further challenge — especially if you do not play recorder — because lifting one finger while lowering another simultaneously often results in an audible “double‑sound”.

Modern phrasing conventions do not always suit this older equipment, and you may be surprised how subtle adjustments to the music make it come alive. A clear example is the Mozart concerto: modern editions push phrases up an octave from the basset-clarinet original, rendering them unplayable on a classical clarinet.

Playing early clarinets soon reveals just how technically demanding the period’s repertoire must have been. Keep that in mind when you breeze through a classical piece on your modern Boehm system. Although historical players were obviously more expert with their instruments, a Molter concerto equals the difficulty of many later compositions, and how would you tackle a Spohr concerto with only ten primitive keys?

Playing early clarinets … as a rewarding and educational experience is strongly recommended.