Acid

Acid sounds like the exact moment heavy metal began to mutate into something faster and more dangerous. It is the sonic equivalent of a high-speed chase in a rusted muscle car, defined by Kate De Lombaert's gritty, commanding vocals and a rhythm section that sounds like it's trying to outrun itself. The production is gloriously unrefined, capturing the kinetic energy of a band that was inventing speed metal in real-time on the European mainland.

What truly sets them apart is the primitive, almost punk-like urgency they brought to the NWOBHM template. While their contemporaries were often polishing their sound for the charts, Acid leaned into the double-bass gallop and the rough edges. Kate's vocals don't aim for operatic heights; instead, they deliver a street-level toughness that bridges the gap between Girlschool's rock and roll and the coming storm of thrash metal.

Start with their 1982 self-titled debut. It is a foundational document of the genre that contains their most iconic tracks like 'Hooked on Metal.' It perfectly encapsulates the transition from traditional heavy metal into the high-octane speed that would eventually influence the likes of Metallica and Venom.