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I flew to Finland to find out...how are amps modeled?

Rick Beato flew to Helsinki, Finland, not for a vacation — but to uncover one of audio engineering's most tightly kept secrets. Neural DSP, the company behind some of the most realistic amplifier modeling plugins available today, has spent years solving a problem that has stumped every other amp modeler: how do you capture an amplifier's entire sonic personality without spending months on each one? The answer involves machine learning, custom-built robots, and a team of engineers who can actually play guitar.

How Neural DSP Actually Models Amps

Beato met with Doug Castro, CEO of Neural DSP, at the company's headquarters in Helsinki. The facility tells the story of five years of relentless engineering — and a space that's already too small.

We model the actual amplifier, not something off a simulator on paper on a schematic.

The company faced a bottleneck: their traditional approach took three months to model a single amp accurately. With hundreds of models needed for their plugins, they realized it would take over a decade to complete the project using conventional methods. So they automated the entire process.

I flew to Finland to find out...how are amps modeled?

The Robot That Solved the Problem

Neural DSP built an internal tool called Tina — a Telemetric Inductive Nodal Automated actuator. This machine moves amp knobs in semi-random patterns, capturing every possible combination of knob positions without physically wearing out the potentiometers.

The challenge was monumental. A single amplifier has hundreds of thousands of possible parameter combinations — bass, mid, treble, presence, drive, and dynamic response interact in complex ways that change depending on how hard the player is playing. Traditional modeling required doctorate-level analysis of each circuit's behavior.

Tina automated this entirely. It sends signals through the amp, records the output, and that data becomes training material for neural networks. The system captures behaviors engineers didn't even know existed — including the mysterious effects of output transformers that no one has ever fully studied because there's no funding for transformer research.

Why This Works Better

The key insight: rather than trying to mathematically model every circuit component from a schematic, Neural DSP treats the entire amp as a black box. Any factor that affects the signal gets captured and modeled — even if they don't fully understand what it is. The result feels and responds exactly like the real amplifier.

Critics might note that this approach sometimes captures artifacts the company doesn't intend to include. But the trade-off has proven worthwhile: the models sound more authentic than anything else on the market.

The People Behind the Modeling

The team at Neural DSP is unusual — most are signal processing engineers who also play guitar or bass. Finding someone with both deep engineering skills and musical understanding is rare.

Doug explained that when they founded the company, they discovered how small the Venn diagram of these two skill sets actually is. Most DSP engineers don't play instruments. The industry treats it like finding a unicorn.

If you find a good DSP engineer that's also a musician... you found an unicorn, a gem.

Neural DSP now has what Doug calls "100 unicorns" — dozens of engineers who can both write code and understand music intimately. They use Python for research and prototyping, then convert the final algorithms to C++ for real-time audio processing that runs in plugins.

The Bottom Line

This piece reveals something remarkable: the most realistic amp modeling technology isn't built by ear alone — it's engineered with machine learning, custom robots, and a team of people who can actually play. Neural DSP's approach of capturing amplifier behavior as a black box rather than trying to mathematically model every circuit has produced results that sound indistinguishable from the real thing. The biggest vulnerability is that some captured artifacts may be unwanted — but so far, the trade-off has been worth it.

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I flew to Finland to find out...how are amps modeled?

by Rick Beato · Rick Beato · Watch video

I've always wondered how guitar amps are modeled. What is amp modeling? Well, amp modeling is creating a digital representation of an actual amplifier, including all the knobs, volume, bass, treble, middle, presence, drive, effects, the speaker cabinets, and even the microphones used to record it. You've seen me use amp models in videos, like when I did a breakdown of Electric Sunrise by Plenny using his neural DSP signature plugin.

In fact, Neural DSP makes signature plugins of many of the people I've had on my channel, such as Matteas Assado, Tossen Abasi, John Patrrui, Tim Henson, and Misha Mansour. When I was on tour in Europe last month, I stopped by Neural DSP in Helsinki, Finland to visit my friend Doug Castro, who is a CEO of the company to learn how Neural DSP models amplifiers. Here's what I found out. Hey everybody, I'm here with Doug from Neural DSP.

We are in Finland in Helsinki at the headquarters. Doug, how are you? >> I'm good, thank you. >> So, show me around.

>> Sure. Well, this is our headquarters. We've been here for about five years. Yeah, we need a bigger office.

We had a very tiny one and it was just one space and it was just like guitars and people stacked on top of each other. So now we have a lot more room. So yeah, we can walk around and let's start from the beginning and we have the sign here. >> This is Rafa.

>> Hello. >> Brilliant electronics engineer, great guitarist, singer. we used to play in a band together in Chile >> about 25 years ago. He started a message board online.

>> Okay. >> And he wrote articles on how to build your own tube amplifiers. >> In Chile, we didn't have tubes amplifiers. Yeah, it was hard to buy.

They were for Chile very expensive, just to have like a Marshall or a Mesa head. >> So he started building his own. He's built his own guitars. He's actually helped me set up all my guitars.

He's like every time I have an issue with a guitar, he's like the doctor. but yeah, so he started this forum and that's where it became the biggest Spanish speaking forum for do-it-yourself effects pedals and tube heads. So you had people from Spain and all over South America who would post ...