San Francisco, CA — November 11, 2025— Sequential’s Fourm synthesizer is a modern powerhouse, but its roots trace back to some of the most iconic instruments in synth history. For our latest sound bank, Punch & Presence: Pro-One for Fourm, we asked veteran composer and sound designer Drew Neumann—known for his work on Æon Flux, The Wild Thornberrys and decades of synth programming—to create 40 presets inspired by the legendary Sequential Circuits Pro-One.
While the Pro-One was a monosynth with a single voice, Fourm offers four voices of polyphony and a more refined architecture. This sound bank wasn’t about cloning the past—it’s about channeling the Pro-One’s DNA into something fresh and expressive. We sat down with Drew to talk about the process, the challenges, and why this Fourm bank easily stands on its own.
Q: Drew, you started by renting a vintage Pro-One for reference. What was your first impression when A/B-ing it with Fourm?
Drew: The Pro-One has snappier envelopes and a wider control range on the ADSR and key tracking. Its filter tuning isn’t super accurate across octaves, but that’s part of its charm. Sonically, it’s rude and metallic, with a smeary resonance quality—some of that is aging components, but honestly, that’s what I remember from the ’80s. And the output level? HOT. It’s optimized for one voice, so it’s punchy. Fourm, on the other hand, is smoother and sweeter overall. Cleaner, more capable. Plus, Fourm gives you four voices—big 8-VCO unison sounds that the Pro-One could never do.
Q: Given those differences, how close can you get to the original Pro-One vibe?
Drew: Straight up—it’s different. The Pro-One is in-your-face, and its resonance gets harsh fast. Keyboard tracking is nearly impossible to dial in for more than a couple of octaves. I can get close, but anyone doing an A/B comparison will notice differences. Honestly, I prefer Fourm for a lot of reasons. It’s solid, expressive, and compact. The Pro-One was great for its time, but it had limitations—no velocity, no aftertouch, and definitely no poly aftertouch. It was the cheapest thing Dave could make back then, and it shows. Still, hit records were made with it because you could buy one for just over $500.
Brassy One
Q: So the goal was “inspired by” rather than “re-created.” How did that shape your approach?
Drew: Exactly. I focused on capturing the attitude—the punch, the presence—while embracing Fourm’s strengths. For example, Fourm’s resonance behaves differently; crank it up and it develops character without getting overly nasty like the Pro-One. In the end, these presets aren’t clones—they’re a modern interpretation of a classic vibe.
Moroderizer
Q: Any surprises or challenges along the way?
Drew: One challenge was that Fourm’s SSI VCOs have a different character than the old CEM3340s, so I had to find workarounds. And sometimes, I’d create a sound on Fourm that was amazing—like a percussive organ patch—but nearly impossible to replicate on the Pro-One. That’s when you realize you’re not just recreating history; you’re also making something new. Some sounds were even inspired by video games of the era, which was a fun twist.
Game Over
Q: We love how the bank turned out! Final thoughts?
Drew: I’m glad you’re enjoying them! That makes my day. I think we nailed the goal—give people something that feels retro Pro-One but also takes advantage of Fourm’s modern polish.
Wubbles
Punch & Presence: Pro-One for Fourm is both nostalgic and evolved. Drew’s 40 presets channel the raw energy of the Pro-One while taking advantage of Fourm’s modern capabilities. Download the bank for free from the Sequential website and experience the best of both worlds: vintage attitude with contemporary finesse.
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