Electric Evolution: The Story of STEREO, Finland’s Electronic Side-Project Phenomenon

When one of Finland’s biggest rock bands, Haloo Helsinki!, announced a well-deserved hiatus following years of relentless touring and chart-topping dominance, fans wondered where the creative energy would go. For guitarists, primary songwriters, and producers Leo Hakanen and Jere Marttila, the answer wasn’t to rest—it was to pivot entirely.

Entering the electronic dance music landscape under the stylized moniker STEREO, the duo transformed from rock icons into electronic architects. What started as a creative outlet during a downtime period blossomed into one of the most exciting electronic pop projects in modern Finnish music history.

From Arena Rock to Electronic Soundscapes

For years, Hakanen and Marttila had defined the sharp, melodic, and driving sound of Haloo Helsinki!. However, the formation of STEREO in late 2018 and early 2019 allowed them to stretch their production muscles in a completely different direction. Embracing heavy EDM elements, slick synthesizer lines, and infectious club rhythms, the duo took full control as songwriters, vocalists, and producers.

Rather than treating the project as a casual hobby, the pair invested world-class standards into their craft. For instance, they enlisted high-profile mixing engineer Miles Walker—renowned for his work with global superstars like Beyoncé, Rihanna, Bruno Mars, and Coldplay—to polish their debut tracks. This attention to detail immediately bridged the gap between Scandinavian pop sensibility and international club production.

The Collaborative Magic of 00740

STEREO’s crowning achievement arrived in November 2019 with the release of their debut full-length album, 00740. Named after a Helsinki postal code, the record served as a vibrant love letter to the Finnish capital’s nightlife, youth culture, and diverse musical landscape.

What truly set the album apart was its collaborative spirit. Instead of carrying every track alone, Hakanen and Marttila invited an eclectic roster of Finland’s finest vocalists and rappers to front their beats. Key highlights from the era include:

• “Vuosien päästä” (feat. Etta): An emotional, high-energy powerhouse track that dominated Finnish radio and streaming platforms, accumulating tens of millions of streams.
• “Sä saat mut palasiksi” (feat. Samu Haber): Featuring the distinctive, raspy vocals of the Sunrise Avenue frontman, this track merged stadium-sized pop hooks with pulsating electronic drops.
• “Woo Woo” (feat. Michael Monroe): A raucous, cross-generational collision featuring the legendary Hanoi Rocks icon, injecting authentic punk rock attitude straight into a heavy dance beat.
• Other Stellar Features: The album also featured contributions from artists like Sini Yasemin, Ida Paul & Kalle Lindroth, Aste, and Teflon Brothers, making each track feel like a unique event.

Impact and Legacy

Though STEREO was conceptualized primarily as a focused project during Haloo Helsinki!’s temporary pause, its cultural footprint punched well above its weight class. 00740 earned critical acclaim, including a nomination for Best Pop Album at the Emma Gala (Finland’s equivalent of the Grammy Awards) in 2020.

The project proved that great songwriters are not confined by genre boundaries. By fusing the raw emotional core of rock composition with the hypnotic pull of EDM, Leo Hakanen and Jere Marttila successfully redefined their artistic versatility. While Haloo Helsinki! eventually returned to active duty, STEREO remains a brilliant snapshot of what happens when established artists throw out the rulebook and follow a fresh, neon-lit impulse.