For those that remember dial-up internet via modems, it’s probably certain that the sound of the internet squawking slowly to life is never to be forgotten. That sound, a digital high-pitched tweety bird call for electrons, was as ubiquitous in quasi-tech savvy homes throughout the 90s as were brick-sized cell phones and 6-disc changing CD players. I would never have thought that the sound of a modem was interesting—and definitely not musical—but here we are where nostalgia reigns, and where 4-bit, 8-bit, and other potentially obnoxious lo-fi sounds are a thing, even cool. Maybe it’s all perspective? One person’s traffic noise is another’s meditative drone, and why not, right?
Along these lines is the latest Schlappi Engineering module, Nibbler, so named because a nibble, which is 4 bits, is half a byte, which is 8 bits. Got it? This is a technical thing. Did I know this before diving into this review? No, I did not. Bytes, bits, and now nibbles, are a less-explored realm in Eurorack, though there are some modules kicking around—Xaoc Devices has their Leibniz system—which delve into this territory. I’d be remiss to say that I’ve had such a system in my possession for a long while now and I understand it less now than I did when it came to me. I’m a bit bit-illiterate as this stuff is a bit (puns intended!) abstract to me, but I’m hoping that maybe if I take it all with baby steps—or nibbles in this case—I can get over my fear.
With an 80s IBM mainframe look, Nibbler has one of those cool old clicky office-lifer computer buttons at the top of the module that seem to have made a resurgence lately, and is a 4-bit CMOS logic thang that’s an accumulator (it can add, subtract, and shift data), and which uses binary information to create quasi-random gates and stepped voltages for making bit-rate audio (like the lovely modem sounds of yesteryear), LFO-y things, rhythmic-y things, and sequences. With a bunch of switches, a bunch of gate inputs and outputs, and a bunch of logic type inputs (shift, XOR, etc.), there are a lot of variations and combinations to learn and explore here.
While the big square Reset button is the visual focal point of Nibbler, the heart of it actually lies in the four demure ADD switches on the left side. These switches (1,2,4, and 8) form the binary word that everything in Nibbler is based off of. With each successive ADD added, there is more pulse signal added to the output. Everything else is something that alters the output of this, but if no ADD switch is up, nothing’s going to happen, so that’s your starting point, making sure an ADD switch is engaged. There are many ways to manipulate the selected bit (ADD) output: the Reset button, which either clears the output while being held in Sync mode or a specific value in Async mode, the Add/Subtract switch, which determines if the ADDs are adding or subtracting, or by inserting various clock or gate input signals for mangling, and even offsetting the phase of the various stepped outputs. You can also reverse the counter by patching into the Sub In, use some of that onboard logic (XOR), and CV the reset. As if there aren’t enough inputs, there are also seven total outputs on Nibbler, two Stepped Outs (an accumulation of the four Gate Outputs + binary weights), a Carry Out (a gate out that goes high when the accumulator overflows, and four Gate Outputs (1,2,4, and 8) that correspond to the ADD input channels. These Gate Outs can be used as clock dividers since they are additions/subtractions of the accumulation of the ADDs as they move down the line, and also to do some self-patching, as can any of the outputs.
It helped calm my nerves to remind myself that this is a lot of unexplored, unknown territory for me on Nibbler, as up to this point I’ve never warmed to binary in modular. It stretched my brain at times, trying to keep up with the concepts that Nibbler delivers. There’s math involved in the theory (and operation), a scary thought, right? It also helped to calm my nerves knowing that I’m not alone in feeling this, as witnessed by my showing Nibbler to a few modular friends, all interested in what it could do, all able to make good use of it, but all unable to explain its inner workings.
Using the Mordax DATA to see what Nibbler is doing is extremely helpful. If all four ADD switches are in the up position, and with a gate signal going into the Clock In to trigger it, and with all four Gate Outputs going into their own inputs on the DATA, you can see the timing relationship of the four ADD channels; ADD1 being triggered at the same rate as the clock signal, ADD2 at every 2 clock hits, ADD4 every 4 clocks, and ADD8 every 8. This is Nibbler at its most basic operation. From there, flipping switches, patching into the Gate Inputs and logic ins, and you can really mangle the output. Using the stepped output as the 1v/Oct source on a VCO, you get a rising melody (or descending, depending on settings), but it’s also easy to randomize the sequence by patching modulation into the Shift Input, or changing the direction of the steps via the Sub In. You can get glitchy via modulation of the Reset Input (or, you know, by smashing the giant Reset button) as well. When you start messing with the switches, speeding up the clock, and use the four Gate Outs into some percussion modules, you can really see Nibbler in its element. Throw CV into the Gate Inputs (along with the clock) and that’s when things can go off the rails, especially when you’re in audio rate modulation territory. Does it sound like I’m getting used to these bits, bytes, and nibbles? Well, I am…a bit, especially when they’re being manipulated by various amounts of CV.
I initially thought that Nibbler would be really good at destruction—as is usual for Schlappi Engineering modules—and while it definitely is, I was really surprised at how well it performs as a sequencer, with a playable Turing Machine-esque repeated randomness behavior thrown in, though not quite as potentially predictable as the TM. The more modulation I patched into Nibbler, whether it was the Gate Ins or some of the logic inputs, the more the sequence shifted, morphing away from its original line. Still, no matter how much it deviated, the sequence never felt fully random; it was still based on something grounded, there was still the thread of continuity somewhere, though I couldn’t always place where.
Playing with the ADD switches adds or subtracts from the output, and this was where I was able to relive my early internet days (together.net, where have ye gone?) with some chiptuned modem sounds, reached via patching an audio rate signal into the input. It made me think of those old 80s noises: modems, arcade games, and fax machines. I started wondering if those tones were just the result of those respected machine’s operations, their life sound, so to speak, or if someone, like an 80s version of Eric Schlappi, intentionally created those noises to go with those machines. Could it be that the annoying fax machine screech was created by a person intentionally? I say that in jest, because while I enjoyed using Nibbler as a sequencer—it’s quite good in that realm—my favorite use for it actually was in the noise creating world. There are a lot of unique AM-y and digitized bit-crushed sounds that I attained, many digital hurricanes, and metallic windstorms to go along with tons of FM and phase modulated sounds.
Nibbler is a good time, and it must be mentioned that the big ol’ Reset button is as advertised, quite fun. There’s a reason they’ve come back recently in things like ALM’s ASQ-1 sequencer, or the CHOMPI sampler, and here in Nibbler. The compulsion to press the dang thing is hard to resist, much harder than when the same buttons first appeared on refrigerator-sized calculators way back when. If you’re like I (was) am, trepidatious about diving into the binary modular world, confused by what that even means, cast aside your fears and embrace the bytes. If you’ve already entertained the world of the bits and bytes, then you already know Nibbler is something you want.

Price: $240
schlappiengineering.com