Now, to be clear, I'm not new to the world of synths. I own a few (including a couple of Volcas) and understand the principles at work. But I'm far more familiar with East Coast, or subtractive synthesis. This is the style of synthesis popularized by instrument makers like Moog, where a harmonically rich sound source is shaped primarily through the filtering, or removal, of frequencies. (This is a bit of an oversimplification, but it will do for our purposes.) This is usually what people think of when they imagine the sound of a synthesizer.
West Coast synthesis, as embodied by the likes of Buchla, goes in a much different direction. Generally, it starts with a simple sound source (in this case a single triangle wave) and then applies various waveshaping functions, like frequency modulation or wave folding, to generate something more complex. And, perhaps just as important, these synths often dispense with the familiar piano-style keyboard.
A modular synthesizer is just that -- it's modular. This means that rather than a predetermined signal path, you actually have to combine multiple synth parts and wire them together to get the sound you want. Now, to be clear, the Volca Modular is what is called "semimodular." That means it is prewired and will make sound right out of the box. But you can reroute the signal using patch cables to achieve different effects.
In short, I was entering uncertain territory when I opened the box. The device I was looking at was clearly a Volca. It's the same size and shape as every other instrument in the series. And it has a lot of the same design DNA, from the recessed touch strip and tiny plastic knobs to the small rivets in the corner of the faceplate. But keyboard had no sharps or flats, there were a bunch of tiny cables in the box, and it had odd labels like LPG (low pass gate) and "woggle." It was honestly a little intimidating.
Thankfully Korg did something a little out of character: It provided useful documentation.
Most Volca's come with one large sheet of folded paper that explains only the most basic functions of the device. The Modular and FM also come with a reference card that allows you to make sense of their somewhat complicated interfaces quickly. But on the back of the card for the Modular are also some simple patching instructions that tell you what wires to connect where to get basic functions like an LFO (low-frequency oscillator) or ring modulation.
The Modular also comes with a second piece of large folded paper that contains a number of example patches. This is about as close as you're gonna get to a preset here. But that's OK. Having to hook up the wires every time I wanted to make a new sound really forced me to learn how the various parts of the synth interacted. I couldn't fall back on an awesome gut-rumbling bass built by a highly trained sound designer at Korg; I had to figure it out for myself.
That said, there is one issue I kept running into time and time again. It turns out, it's hard to get something that you would call traditionally musical out of the Volca Modular's two analog oscillators. It is, by design, kind of weird and abrasive sounding. It excels at noisy squelches, percussive clicks and metallic stabs. If you're hoping to get delicate pads or a classic synth lead sound of this, you'll be sorely disappointed. But if you've ever wondered what a bunch of water droplets would sound like if they did a pile of cocaine, well, the Volca Modular might just have the answer.
As atonal as most of the sounds it produces are, they're still quite fun to mess with. The eight modules and 50 patch points give you so many different combinations to explore. And the range of noises the Modular spits out are unlike anything else in the Volca range. The Volca Keys, Beats, Bass, Kick, Drum and even FM are all pretty straight forward. While the FM can be difficult to program, all of them are relatively immediate and fill familiar musical niches. The Modular, on the other hand, is far more experimental, far more alien and requires far more patience to get the most out of it. I do not mean that as a negative, though. It just makes the Volca Modular unique among Korg's lineup of entry-level synths.
Like the rest of the Volca range, there are sacrifices made to keep the instrument portable and battery-powered. The knobs are small, and in poor lighting, it can be difficult to tell where they're set. (I've used a white-out pen to mark the notches on my FM and Keys for better visibility.) Tiny adjustments can have a huge impact on the sound, too, which can make recapturing something you like problematic. The speaker is also passable at best. It's nice that you don't have to plug in headphones or an external speaker to get sound from a Volca. But the internal one is kinda small and tinny.