Klavis - Logica Gater


Sophisticated logic module – The Logica Gater comes equipped with seven mathematical functions, which can be chosen by hand or via a CV input. Up to three input signals plus manually added gates can be involved in the module’s calculations. Results are emitted at a normal and an inverted output. Additionally, there is a flop-flop connector, which changes its state just once per generated signal. – More or less an output working with a division of two.



The Logica Gater offers seven mathematical functions. Signals are fed to the module via three inputs. Additionally, there is a button for adding gate voltages manually. Alternatively to one of the seven functions, the Logica Gater can be put in a permanently active or inactive state. Algorithms are chosen via a potentiometer and / or a CV input. Since the Logica Gater not only features a normal output, but an inverted one as well, it is possible to use the circuit for other calculations as well:

Normal output

  • And
  • Or
  • Xor
  • Even
  • 1 Low (on)
  • 1 High (on)
  • Gater

Inverted output

  • Nand
  • Nor
  • Xnor
  • Odd
  • 1 Low (off)
  • 1 High (off)
  • Gater inverted

Gater isn’t a typical logic function. While this mode is active, the Logica Gater combines all inputs as the Or function does, but retriggers the output every time a new gate signal is detected.

The flip-flop output changes its state every time the main output transitions from off to on.

The Xor function can be employed as a digital ring modulator. Similar circuits were used in synthesizers like the ARP Odyssey or the Korg MS-20.


Three signal inputs
Mode CV input
Normal, inverted and flip-flop output


3U Eurorack module, 5 HP wide, 25 mm in depth
Power consumption: 0 mA at +12 V, 16 mA at +5 V and 1 mA at -12 V

0.15 kg
Article Number

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