The Instrument
World flutes are extraordinary instruments, all with unique tones and color palettes. We, Justin and Garrett, set out to create an instrument that keeps the essence of traditional world flutes and unites it with a modern platform.
The RolBec Flute is an open–tone hole duct flute pitched in C4 with a standard range of 2.5+ octaves and a 3+ octave extended range. The instrument is chromatic using our 10-hole system. Our sound source designs allow for solo projection while maintaining a large dynamic range with minimal pitch fluctuation.
The Architecture
The RolBec Flute features our Modular Acoustic Architecture allowing the artist to individualize and explore unique color palettes. It utilizes the intuitive playability of a 2-chamber duct flute design. A tapered headjoint, adapted from Boehm flute design, tune the overtones and control pressure distribution in the resonating tube. The headjoint shell houses the three independently interchangeable inserts (mouthpiece, windway, and edge). Each insert changes a different part of how the sound is produced. The mouthpiece insert changes the chamber the air enters and how the instrument feels to play. The windway insert compresses the air into the flue and shapes the air jet. The edge insert changes the window the air jet crosses and the cutting edge it strikes. Together they control color, tone, focus, and projection.
Our movable beard attachments, adapted from pipe organ designs, allow the artist to change the instrument’s voice (volume, tone, and feel) while playing.
As a world flute inspired instrument, performing in modern music settings as well as world music settings was of high importance for us. The RolBec Flute has four tuning joints: headjoint to neck, neck to upper body, upper to lower body, and lower body to footjoint. Tuning rings at each joint set the overall length and ensure consistent playability from continuity of the bore while giving a tuning range of 430-450 Hz/±40 cents.
The tuning ring standard configuration is 10-10-5-5 mm. It can be reduced to 0-0-0-0 mm and extended to 20-20-10-10 mm. The two lower joints sit below the tone hole sections and adjust the tone hole tuning when moving to a different pitch standard. The two upper joints sit above the tone holes and on both sides of the neck bend. As long as their combined length stays the same, the flute keeps a consistent tuning. By rearranging the location of the tuning rings between the two joints (for example: 10-10-5-5 to 0-20-5-5) the artist shifts the location of the bend, changing the color and response without changing the tuning.
The Reasoning
We sought to create an instrument that is acoustically robust and can perform alongside a grand piano in a concert setting. To accomplish this, we combined a large 30mm bore size with a wide flue and cutting edge. The window measures at 28 mm with a cutting edge following the contour of the bore resulting in a length longer than the diameter of the bore itself. This design maximizes the air jet being used to create the sound. Measuring at 1 meter, C4, the lowest note, registers at 90 dB while the first octave can hit 96+ dB and the upper registers are capable of 105+ dB.
The concept of the oblong tone hole came from two distinct ideas merging to create the final design. First, the oblong shape terminates the air column more cleanly, acting like a bore that changes length rather than a vent. Second, the shape follows the contour of the finger pad, which also allows the artist to cover a larger opening than an equivalent circular hole. Our oblong tone hole has an area opening of a 10.97 mm equivalent circular tone hole. Additionally, the oblong shape results in a brighter and more colorful sound, smooth glissandi and microtonal pitch accessibility.
The tone holes are rotated laterally around the bore to mimic the natural finger position for ergonomic hand placement. Raised finger plates let us set tone hole height independently of bore wall thickness. We get the acoustic benefit of the taller tone hole chimney, a more focused tone and greater projection, without thickening the entire body and adding unnecessary weight. Additionally, the finger plates feature our contoured design following the natural shape of the finger pad along its length to allow for a natural “bed” for your finger pad to sit in and efficiently seal the tone hole.
How It’s Made
Our designs required new methods of manufacturing woodwind instruments. These processes produce isotropic parts with an accuracy of ±0.02 mm for the inserts and ±0.3 mm for the body. The insert process and materials (Sterolithography and Resin) produces the highest level of accuracy possible for the sound source. The body process and material (Multi Jet Fusion and PA12s) has a density of 0.95 - 1.02 g/cm³ matching fine woods used in Western woodwind instruments. Our instruments are manufactured in California. Together, these ensure every artist has a consistent platform to craft their sound.
The Creators
As saxophonists and doublers, we wanted to incorporate many different standards found within the professional woodwind realm including customization and ergonomics. Designs we implemented include a neck bend to place the hands in a natural position, a neck strap ring, and individualization of the instrument like a saxophonist’s mouthpiece, reed, and ligature through our headjoint inserts. Our backgrounds allow us a different perspective to create an instrument that is quickly adaptable and works fluidly with the artist.
The Process
We started with PVC to prove the concept and slowly replaced one part at a time with resin until we reached the material limitations, forcing the final shift to HP Multi Jet Fusion. We have had hundreds of redesigns in CAD and thousands of combinations played and compared before settling on the current parameters. We still have boxes of the old prototypes.
We test each parameter in isolation. A design only moves forward when we know which change produced the result.
