Product Design

Our fundamental desire as flute maker is to dedicate our craft to creating flutes that perform as true partners with every player. We would like to interact with players, not only to gain their satisfaction and trust from them but also to express our craftsmanship through their needs. In order to make a more reliable flute as an extension of the artist, it is necessary to deepen our understanding of musical expressions and their methods by interacting with many players who love the flute. 

Material Selection

We offer four different types of silver: 946 Silver (exclusive supply to Altus Flutes, and thus dubbed the "Altus Silver"), 997 Silver made with powder metallurgy, 958 Silver (Britannia Silver), and 925 Silver (Sterling Silver).

Altus offers a selection of exceptional materials for players to choose from, each with its own character. This allows each player to choose one that is best suited to their individual preferences.

Four kinds are available for silver material alone: Sterling silver with a silver content of 92.5% is the most standard material for flutes. We also offer Britannia silver with a silver content of 95.8%, Ag997 pure silver with a content of 99.7%, and Altus silver which was born after trial and error, pursuing the tone of old French flutes, with a silver content of 94.6% and several other elements. Since each material has a different density, hardness, and ductility, it naturally leads to differences in the flute-making process.

Tubing & Metallurgy

The differences in density, hardness, and ductility of each kind of material naturally lead to differences in the flute-making process, maximizing the overall performance in terms of tone and harmonic structure.

The AL and 1607 are manufactured with a seamed tube, a method used by the great old French flute makers, where a single metal sheet is rolled, shaped, and soldered forming the tube. Compared to ordinary drawn, seamless tubing, the seamed tube method is more time-consuming and requires great skill. As the flute is played over time, the residual stresses in the metal gradually dissipate and the molecular arrangement changes to a more ideal form for producing sound.

A pure silver flute possesses supreme projecting qualities and it requires cutting-edge technology to produce. Powder metallurgy is the method used for processing silver of such high purity, in our case , .997 silver that is standard on the Altus PS. Usually, pure silver is too soft for successful flute tube production using traditional methods, where metal is melted. However, powder metallurgy makes this possible, and has benefits to not only the sound quality but also the durability of the instrument.

Altus Scale

Our own scale with ideal harmonics meets players' requirements and preferences.

All Altus flute models utilize the Altus Scale.

A flute's scale contributes to the overall tonal quality and harmonic structure, and the Altus Scale meets the player's requirements and preferences. The scale is the culmination of years of research and development in collaboration with Mr. William Bennett, one of the world's foremost musicians and a leading authority on flute scales. The core value has always been simple: to produce a sound with the right harmonic structure at the right pitch. The meticulous design of the Altus flute and its uncompromised scale offers excellent intonation, carefully tuned harmonics, and balanced registers.

The resulting scale is highly recommended and desired by many players. It features a soldered C# tone hole as standard on all models. The C# tone hole operation is especially important in the Boehm system and has multiple purposes. It not only produces the original C# note, but it also acts as a vent hole for many notes. The ideal scale requires having its specific key height set properly. Our design is also based on the condition that the headjoint draw is 5mm and in an environment where the temperature is 21-23 degrees Celsius.

Key Mechanism

Delicate mechanism and smooth key actions.

Flute key mechanisms consist of rods, keys that rotate around the rod, and posts that support them. Compared to a conventional key post design, Altus adopted a combination of a tapered convex part and a conical concave part on the king post between the right-hand and left-hand primary keys. By adopting this shape, the connection of the parts becomes a line rather than a surface, achieving both precise construction and smooth key action. This kind of design requires skill to adjust and is more commonly found only on high-end models - however, we utilize this design on all our models.

Soldered tone holes

"Gold solder" hardly deteriorates even after years of use.

Altus uses gold solder for the tone holes on handmade soldered models. Conventional solder can, over time, develop gaps between the tone hole and the tube caused by several factors. Altus uses an 80% gold alloy solder, maintaining the long-term structural integrity and performance of the flute.

Posts and Ribs

The rib brings out the true sound of the flute tube.

The vibration of the flute tube affects the sound, and is influenced by the ribs and key posts. All Altus flutes are equipped with a wide rib that touches the sides of the tone holes, rather than the conventional style which is set back from the tone holes. This kind of design takes more time and effort to manufacture, but it is worth it as it significantly reduces unwanted vibration from the keys. This accentuates the characteristics of the various tube materials.


Spring made of "SP-1", with excellent elasticity.

The unique Altus SP-1 springs, made from an alloy of precious metals including silver, gold, and platinum, provide excellent elasticity, which results in a light and responsive touch to the mechanism. The SP-1 spring is used in 1207 and higher models. 

Key Pipes

The keypipes are made of high-purity silver for extra durability.

Our all-silver models have keypipes made from powder metallurgy pure silver. The characteristics of this material contribute to a longer lifetime, as it is stronger and less prone to twisting, allowing for a more reliable mechanism.