Dual Passive 4HP Sidechain Limiter
A very simple sidechain limiter: when the level of the sidechain input goes over a threshold determined at build-time, the main signal will be attenuated temporarily. This uses an optical system, which gives a pleasing attenuation curve and complete electrical isolation, preventing e.g. hums from connecting remote systems together. Two independent channels.
The module is not design to gate: typically it should give 6db attenuation at typical maximum, i.e. it will halve the signal volume. While it can be used to provide the “pumping” effect, this will be medium-mild not extreme.
This module can also be used as a voltage-controlled attenuator if a DC voltage is applied instead of an audio signal to the Sidechain In. Similarly, the main in can also be a DC signal, instead of (as well as) the expected audio signal.
Sidechain In/Distort Out can also be used as a soft-clipping distortion unit. There may be distortion at maximum attenuation, if using LEDs that in part have very fast response in audible frequency range.
BONUS: Each Duck PCB/Panel ordered will come with 2 LDR (Light Dependent Resistors) and suitable heat-shrink tubing.
The module is passive; it does not have a connection to the Eurorack power bus.
Technical: Nominal 6db attenuation. Complete electrical separation of both limiter-effected circuits. DIY vactrol driven by sidechain signal wit threshhold over +/-2 to 9 V as selected. Plus additional output for distorted version of Sidechain signal.
Physical: 4HP , 35 mm deep, passive (no power)
Status: Available
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