Mutant BD9 (original)

analog 909-inspired bassdrum synthesis with sub-oscillator

Parametric bassdrum synthesis offers creative control of the core sound
The primary analog VCO offers classic 909-esque sinusoidal bassdrums, but can also be switched to generate a square wave bassdrum
The PITCH of the VCO spans several octaves, from about 30Hz to 240Hz, and can be modulated with voltage control
A novel PITCH DECAY circuit allows you to adjust the duration and AMOUNT of the pitch-modulation envelope applied to the bassdrum, from short blips to exaggerated tom-like sweeps
The AMPLITUDE DECAY allows adjustment of the length of the bassdrum, from short punchy kicks to massive booms. This parameter is voltage-controlled with a snappy CV response time, allowing you to modulate the duration of your kicks per step.
The CLICK generator is responsible for the attack intensity of the BD9. A fair amount of circuitry goes into creating this subtle punch at the beginning of the kick. The level of this effect is adjustable up to a fairly dramatic extremity.
The overall timbre of the BD9 varies with the DRIVE control from warm, analog bassdrums at low settings to speaker-shattering overdriven sounds at high settings. Output levels are modular-level signals, unlike many classic line-level percussive devices.
Still not heavy enough? Try the sub-oscillator.
A square wave sub-oscillator derived from the primary oscillator's pitch can be mixed in (manually and with voltage control) to the BD9. The effect can be subtle deepness or extreme timbre changes.
A jumper on the back of the module allows you to select between the sub-osc being a raw square wave or having some of the high frequency components removed with a lowpass filter.
At high OUTPUT DRIVE and SUB LVL combinations, the sub-oscillator can be modulated with CV to saturate the BD9 output in evolving ways.
The SUB OCT can be set to 0, -1 or -2 octaves down from the primary oscillator. A drop of 0 means that you can mix an equal-pitch square wave with a sinusoidal primary wave.
Designed for the contemporary modular synthesizer
Plenty of eurorack-compatible control voltage inputs with bipolar attenuverters allow synthesis of dynamic percussion
A practical analog trigger circuit allows activation of the BD9 from many signal sources (anything with a positive-going edge lasting 2ms or longer). Most electronic drum pads can also directly trigger the Mutant BD9.
An accent input accepts analog voltage control (0 to 5V will fully modulate the volume from low to high)

50 mA +12V
50 mA -12V
0 mA 5V
30 mm deep