Dirt Box
The dirt box is a bass synth primed for powerful bass and tunable grit. It has a digital oscillator powered by an 8-bit microcontroller with a range of waveforms from soft sub-bass to mangled waveforms full of gravel and metallic overtones. The digital oscillator is coupled with a digital resonant low-pass filter for extra tonal control.
The oscillator feeds into a transistor wave folder with gain and distortion controls. The gain knob pushes the waveform harder into the wavefolder, adding volume and folding the wave in on itself, creating rich harmonics. The distortion knob adds clipping for dirtier, heavier tones. The combination of unique waveforms, digital filter, wave folder, and distortion allows you to find exactly your flavor of dirt.
At the end of the signal chain is a discrete VCA with a single decay knob feeding into an output amplifier with bass boost. All in all, the dirt box has been engineered for maximum bass and a broad range of aggressive tones full of character.
The dirt box has two play modes: sequencer and keyboard. In sequencer mode the dirt box plays a 16 note pattern and the five buttons are used to enter regular notes, glide notes, modulated notes, and noise notes. The fifth button erases the current note. The position of the pitch and octave knobs determine the pitch of the note entered. In this mode it is very difficult to be precise about what you create: the inaccuracy of the process encourages an intuitive approach that produces accidents and unexpected patterns.
When you need control you can stop the sequencer and the five buttons become a keyboard that plays a five-tone scale. The pitch knob determines both the octave of the scale and whether the five tones are major or minor.