DIY Kinks (Black Magpie)

Kinks is a utility modulator for Eurorack with 3 main functions.

SIGN
This section consists of a precision signal inverter, as well as half-wave and full-wave rectifiers (which respectively clip to 0V, and invert the negative half of the signal).
They can help in creating new LFO shapes, add overtones to audio signals, or even transform CV melodies.

LOGIC
An analog OR gate outputs the maximum of two signals: not only it can merge two streams of triggers/gates like its digital counterparts, but it can also hybridize LFOs, envelopes, or even audio signals – creating the same type of inharmonic side-bands as ring-modulators.
The analog AND gate outputs the minimum of the two signals. With it, you can mute/un-mute a stream of triggers with another gate, or explore other shades of audio and CV mangling.

S&H
A no-nonsense implementation of a classic synthesizer circuit.
On each trigger received on the TRIG input, the output voltage takes the value of the input voltage and holds this voltage.
The signal input IN is normalized to a white noise generator – to easily generate stepped random values.
The white noise signal is also available through the NOISE output jack.

Specifications

• Width: 4hp
• Depth: 25mm
• +12V Current: 25mA
• -12V Current: 25mA
• All inputs DC-coupled.
• All circuits handle audio-rate signals.
• Input impedance: 66k for RECTIFY, 90k for LOGIC, 1M for S&H.
• S&H TRIG input edge detector: minimum pulse width: 25µs. Maximum slew rate: 0.2V/ms.
• S&H sampling time: 100µs.
• S&H droop rate: <0.8mV/s.
• Noise output: flat from 10 Hz to 30kHz (-6dB/octave roll off beyond), standard deviation = 1.8V +/- 10%.

PCBs are made by synthCube in blue material with a blue immersion gold finish.
Panels are designed and produced by grayscale.