Application Why Bother With Experimentation?       The appreciation of other instruments has been a very important part of my journey with the flute. I believe that each instrument has a special viewpoint of expression that it lends to music as a whole. As a flutist, to sigh like a cello helps to open to a new area of reflection. As the idiomatic approaches to ones favorite instruments are added to the musical lexicon, the flute becomes more open and supple. Each instrument derives its sound from the vibration (strings, winds, etc.) but the inflection comes from the interface. The user interface to a musical instrument is the control surface—a flute fingerboard, a fretless neck, etc. As a maker, I wanted to explore working with these variables.       What about controlling non-flute-like instrument consoles from a flute fingerboard? (The Tracker Flute, a flute clavichord, a flute melodica.) What about applying a sophisticated slide whistle control surface to the flute? You can control the flute with a non-flute-like interface or control non-flute-like sounds with the flute. Instruments have been added to our musical family in modern times; look at the saxophone, vibraphone, or theremin! Modes of sound generation are still being investigated and discovered; there are new instruments around the corner! What will they tell us about sound itself?       Why experiment with non-flute-like instruments? In some of my experiments, I have tried to move beyond the flute, beyond music—to sound. Most instruments produce a sound by resonating either a chamber or a waveguide. In order to look more deeply at this, I built the waveguide guitar with a very long, air-tight coil to resonate the sound instead of a large open chamber. The Pipatar looks more at interface. The formula governing vibration of a string involves the variables of mass, length, and tension. A standard guitar interface changes length in real time while the Pipatar changes tension. Taking these ideas back to the flute opens the mind to new possibilities. Changing the approach to vibration and interface led to the development of the Whammy Bar headjoint and Octorina.       We just need to keep thinking and stay open. If a regular bass guitar plays just C, C# and D like a flute but a fretless bass plays all the in-between notes like Jaco Pastorius, what would the flute analog be? Hmm. . . . . . the fretless flute....