The Lifeforms Dynamic Impulse Filter from Pittsburgh Modular is a variable-response low-pass gate that combines three functions into a single module, including a resonant lowpass filter, a high-quality VCA, and a combined lowpass gate mode that manages both timbre and loudness at the same time. The core of the filter uses a Sallen-Key topology to produce a smooth two-pole filter that will self-oscillate at high resonance settings.
Most lowpass gates utilize a vactrol, a light-dependent resistor that lends itself to organic percussive sounds with a natural decay. The dynamic impulse filter employs a newly developed dynamic response control circuit that emulates a vactrol's sonic characteristics, but with a variable response time that is tunable and adapts to any musical context. The impulse trigger input and the dynamics response control allow the module to add an organic, percussive quality to any sound, or become a versatile analog drum generator. The dynamic impulse filter will uniquely emulate everything from snappy deep kicks to woody toms and expressive hand drums, opening up a new world of electronic percussive sounds. The Lifeforms Dynamic Impulse Filter module is 8hp wide, 0.8" (20 mm) deep, and requires 35mA of power. The module includes a ribbon cable.
- Dynamics Response Knob: Sets the decay time related to the impulse gate input and dynamic CV input
- Dynamics Knob: In filter mode, the dynamics knob controls the center frequency of the filter. In VCA mode, the dynamics knob controls the pass-through signal level. In low-pass gate mode, the dynamics knob controls both the center frequency of the filter and the pass-through signal level
- Dynamics CV Knob: Attenuates the incoming dynamics CV signal
- Filter Mode Resonance Knob: Only active in filter mode, the filter-mode resonance knob controls the amount of resonance
- Mode Switch: Switches between the 3 module modes. VCA position (up) enables VCA mode, both position (center) enables lowpass gate mode, and filter position (down) enables lowpass filter mode
- Input Jack: Audio signal input
- Dynamics CV In Jack: CV input used to modulate the dynamics amount
- Response Out Jack: Dynamics response CV output. This output is optimized to control the vactrol response of modules utilizing vactrols. It is designed to be patched into a CV input. The Response Out jack will respond like a gate when used with non-vactrol modules
- Impulse Gate In Jack: Gate or trigger input used to strike the vactrol and quickly modulate the dynamics of the audio signal
- Out Jack: Audio signal output