The Pronomos Flute
How is the Pronomos different from other quarter-tone flutes?
The important feature of the Pronomos flute is the optional independence of all keys. For example, on a standard flute, any key fingered by the right hand, R2, R3 or R4, automatically closes the F# key via any one of three clutches. The Pronomos however allows a normally-closed duplicate G key (covering the extra G hole) to be opened while any of these fingers are down, so offering a multitude of new cross-fingerings. This key is of the “key-on-key” type, so allowing the ¼ tone F# up.
The same applies to the Bb in the left hand. This slave or non-fingered key is duplicated too. So while A is fingered, the duplicate, normally-closed B key (called B because it now has the same name as its hole), or its small “up key”, can be opened by the right thumb.
There is the common split E mechanism with a disengagement switch, while the lower G key can be closed easily with L4 and independently of the upper G key.
On the foot joint, the clutch between C and C# can be disengaged. The usual D# lever is split into two parts, a central slightly raised area produces D# whereas pressing the surrounding area produces D up. Various gizmos allow R5 to press any two keys together, again for cross-fingered effects. The foot joint alone allows 24 different combinations of open or closed keys; this figure doubles to 48 if the end of the tube can also be closed, such as by the knee.
Many of the special tonal effects achievable with the Pronomos are the result of combinations of fingered keys, either by cross-fingering or by using one finger to press two or even three keys at once. Mr Matuz calculated the total number of possible fingerings on this flute as 4,723,920. In its latest form the Pronomos can offer no less than 23,000,000. So it would perhaps be more correct to call this a microtonal flute as there are so many available notes in between the quarter tones. The vast acoustic panorama that can be opened in this way will only be limited by the player’s imagination, but it may be comforting to know that one can always come back to a Bach sonata on the same instrument!