The Brown Acid compilations have been collecting hard-to-find and obscure hard-rock tracks for more than two years now. The series' sixth volume, Brown Acid: The Sixth Trip, will be released on April 20.

We have an exclusive premiere from the set – a four-minute blast of psychedelic proto-metal called "Inferno" from the Canadian band Heat Exchange – that you can check out below.

The song dates from the A-side of a rare 1968 single, and like other tracks found on the Brown Acid compilations, the music serves as a bridge between the louder side of the '60s garage-rock spectrum and the following decade's move into heavier sounds.

The upcoming album includes 11 cuts by little-heard bands that slipped through the cracks over the years. But that doesn't mean they don't deserve some attention. Songs like Gold's ferocious "No Parking," the riff-heavy and reverb-drenched sway of Travis' "Lovin You," and Truth & Janey's bluesy stomp "Midnight Horsemen" are lost nuggets from an era that churned out gems like these on a weekly basis.

Heat Exchange's "Inferno" is one of our favorite cuts on Brown Acid: The Sixth Trip. It sounds a little like a soul-kissed Cream working their way toward the '70s, with a killer riff as their guide. The Toronto group originally released the song on the Yorkville label; it was later included on a compilation that collected Heat Exchange's handful of singles. It sounds right in place on the upcoming volume with other unearthed chunks of guitar-driven rock 'n' roll from the period.

We're huge fans of the Brown Acid series, which gathers largely forgotten garage, psychedelic and stoner-rock tracks from the '60s and '70s. Think of it as a companion to the essential Nuggets compilation but covering artists and records that never made it out of their hometowns. Brown Acid: The Sixth Trip is available for pre-order directly from RidingEasy Records now.



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