The original Martinetta has been played with the help of a small wind tube. Here the wind goes trough the tube to a small pipe, so that the player got the typical blowing noise with the characteristic edge tone. Behinde the pipe was a small microphone, which transfered the pressure fluctuation into voltage fluctuations. After a low pass filtering these fluctuations have been used as control voltage for the width, shape and hight of the pulses generated in the sound processing unit, as well as for the transients (beginning and ending of the sound) and the small timbre modulations.
The Variophon works like the Martinetta. but it has a recorder-like mouthpiece, so there is no tube with a small pipe and no edge tone. The player can add a artificial blowing noise with the help of a noise potentiometer. He can also adjust the instrument to his personal breath intensity, while a LED chain shows the dynamics from pp to ff.
The Variophon gig has also the possibility to influence the modulations (caused by the musicians breath) in two ways: With the help of the "Frequency Modulation" potentiometer the player can adjust the strength of the vibrato and with the help of the "Spectrum Modulation" potentiometer the player can adjust the strength of the fluctuations of the partials (timbre modulation).
In the blow controller the players breath gets transferred with all its fluctuations in a fluctuating controlling voltage, which influences the pulse forming sound generating process and the circuitry of timbre dynamics.