NIJEL is a diode distortion module that has drive control via a knob and/or incoming control voltage (CV). The user can optionally modify the distortion character by plugging passive electronic components like diodes, capacitors or resistors into either or both of two rows of ports on the front panel, or special pre-made cards that contain small circuits made up of such components. NIJEL comes with a small set of suitable passive components for experimentation: a photoresistor, diode, LED and capacitor.

The ports at the top of the module labeled P|S|G|S|P support the plugging in of pre-assembled cards available from Neutral Labs, as well as individual passive components like resistors, capacitors or diodes. LEDs and LDRs (light-dependent resistors) can be used as well, even in combination. Any combination of components and/or cartridges will change the distortion behavior in its own unique way. There are 2 rows of ports which work exactly the same, and they can be used at the same time. E.g. it is possible to connect two cartridges to both rows of ports simultaneously, or one cartridge and a number of components on the other row of ports. When using cartridges, their orientation doesn’t matter, they will work the same way facing either up or down. Caution: As shown by the warning icon to the top left of the ports, do not use normal (unipolar) electrolytic capacitors unless you know exactly what you’re doing! Reverse voltage may make them explode violently. You may use them with the positive leg on one of the P ports and the negative leg on one of the G ports, but it is better to avoid them completely. Large value bipolar ceramic capacitors are easily available and should be used instead. The use of active components like transistors could result in unexpected behavior and might damage the module, so avoid them as well. An exception would be a BJT with either its emitter or its collector leg remaining unconnected. Rule of thumb for the novice user: Plugging in any kind and combination of diodes, resistors and ceramic capacitors is always safe.