Schlappi EngineeringNibbler CMOS Four-Bit Digital Accumulator

Schlappi Engineering Nibbler

Putting the power of CMOS logic and shift registers at your disposal, the Schlappi Engineering Nibbler is a patchable playground for creating rhythmic patterns, sequences, and more. In more technical terms, Nibbler is a four-bit digital accumulator, with four bits corresponding to a total range of 16 values. Inputs for each bit allow you to add values of 1, 2, 4, or 8 to the accumulator, and stages are connected via a bit-shifting register to pass states from one bit to the next. However, you don't need a strong understanding of binary to get a lot out of Nibbler—once you start patching things in, you'll quickly pick up on how much you can do!

Data is fed into Nibbler via switches at the top left of the module or gate inputs into each stage. Unique compared to some other registers, you can insert data into any point of the register, and internal data is looped back around and XOR'ed against Stage 1's external input. Each of Nibbler's stages features a dedicated gate output, allowing you to create four-step sequences and patterns. These are also combined into a weighted sum at two Stepped Voltage outputs, letting you create variable sequences depending on the active state of each bit. The second output also features optional phase offsets to distinguish it from the other, giving you more options in patching around your system.

Nibbler offers a number of handy controls to create more interesting behaviors. Sync and Async modes allow you to decouple the Clock and Shift inputs, while Add and Subtract modes change the direction of register incrementation, but a dedicated Subtract input allows you to dynamically create variations on register data. And if you ever want to clear the register and start fresh, a Cherry MX Brown switch at the top gives you a tactile and satisfying way to do so—of course, an external Reset input is also available for patching. Explore the musical worlds of binary counting with Nibbler by Schlappi Engineering.

Nibbler Features

• Digital accumulator and shift register
• Discrete CMOS design, no CPU involved
• Operates at control and audio rates
• Four stages arranged in bit-shifting register
• Manual and external signal inputs for gates
• Clock and Shift inputs with Sync/Async operation
• Add/Subtract modes for register
• Carry In/Out for chaining Nibblers for larger registers
• Stepped voltage outputs, one with phase offsets
• Cherry MX Brown switch for reset
• External Reset input