The Innovators: Douglas Castro of Darkglass Electronics

Growing up in Chile, DouGLAS Castro aspired to be a professional bass player.
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Growing up in Chile, DouGLAS Castro aspired to be a professional bass player. “I realized that making a living playing music would be challenging, so I decided to study electronics,” he says. “My idea was that I could repair my gear and also make gear for other players.” His initial product concepts culminated in the Microtubes B3K CMOS Bass Overdrive and B7K Analog Bass Preamp; he built the first pedals in his living room with the help of his brother, getting a foothold in the effects market.

As he learned more about electronics, Douglas discovered that designing and building products for other bass players was as gratifying to him as playing music. Then, at the age of 21, he moved to Helsinki, Finland, where he had spent a year as a high-school exchange student. “I had enough money to live for about a year,” he says. “I was renting a workspace in 5by5, a recording studio owned by Matias Kupiainen from Stratovarius. Those guys really helped me out a lot. It was tough at first, but it was great. I had to learn how to deal with the pressure and to develop the relentlessness that it takes to grow and run a business.”

The Darkglass B3K was a hit right from the start. In a Bass Player review, Jonathan Herrera called it “super-hip” and stated, “Of the many, many overdrive pedals that have come across my desk, the B3K is among the most tube-like I’ve bumped into.” The B7K has also been well received, and more products have followed, including the Duality Dual Fuzz Engine, the Vintage Deluxe, and such variations as the Microtubes B7K Ultra and the Vintage Ultra. Their widespread acceptance is evident at the Darkglass website, where the Artists page displays photos of more than 100 bass players.

In the past year, Darkglass took a big step with the introduction of the Microtubes 900, an amp head with a Microtubes analog preamp and 900-watt Class D power module. “We showed an early prototype at NAMM in January [2016],” Douglas says, “and we released the final version in September. It took a couple of years of hard work by a full team—but the reception has been amazing.”

Douglas is planning to produce speaker cabinets matched to the Microtubes 900 head and is considering other ways to expand the Darkglass line. “I’ve hired more engineers, and we’re diving into some cool stuff. I’m always thinking, What will people need? How can we get there, not in ten or 20 years but in one or two years? My focus is on building the next generation—and thinking that way has opened my eyes to what could be accomplished with the right team.”

Looking down the road, Douglas says he wants to “build a company based on excellence, focusing on constantly improving every aspect of the operation, and let growth take care of itself. I would like the company to be as big as it can be as long as it doesn’t compromise our values.”

Central to those values is customer service. Douglas spends a great deal of time listening to and evaluating feedback, not only from such well-known artists as Tony Levin and Bryan Beller but also the working musicians who contact him directly or engage in online conversations about Darkglass products. “I think it’s important to listen to users,” he says. “I have to trust my instincts when I’m designing, but once a product is out, it’s helpful to listen to what the people who are buying it and using it with their bands and in their studios have to say. I’m as active as I can be in forums, learning how to improve our products. It’s the regular users who give us the most valuable feedback—and when something comes out and people really love it, it feels amazing.”

For more about Darkglass Electronics, go to

Jim Roberts was the founding editor of Bass Player and also served as the magazine’s publisher and group publisher. He is the author of How the Fender Bass Changed the World and American Basses: An Illustrated History & Player’s Guide (both published by Backbeat Books/Hal Leonard).


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