The midi note range is not fixed to C2-C7 because you may assign any midi reference note to the Dark Energy. The reference note is
the lowest note that is expected from the midi transmitter. In the factory the Dark Energy is adjusted that this midi note
corresponds to ~65Hz (octave switch and tune control in center position) which corresponds to C2. With the octave switch down it's ~
32.5Hz which corresponds to C2. If you want a lower pitch you may adjust the internal frequency offset trimming potentiometer
(details in the technical document on our website).

Best wishes
Dieter Doepfer