For the past six years, the Brown Acid series has been delivering rare garage rock and proto-metal tracks that have been buried deep in the archives since the late '60s and early '70s.

The latest volume, Brown Acid: The Thirteenth Trip, arrives on Oct. 31 and includes 10 more long-lost songs by artists who never made it too far from their North American hometowns.

We have an exclusive premiere of one of the set's highlights, Gary Del Vecchio's "Buzzin'," which packs a whole lotta Zeppelin- and Sabbath-like riffage into its three and a half minutes. You can hear the song below.

Like many tracks included in the Brown Acid series, there's not much known about Del Vecchio. The original song was officially credited to Gary Del Vecchio and Max, who are not the band with the same name that kicks off The Thirteenth Trip with the equally galloping "Run Run."

Other highlights this time around include John Kitko's "Indecision," Master Danse's "Feelin' Dead" and Dry Ice's excellently titled "Don't Munkey With the Funky Skunky." Each sounds like a bridge between primitive '60s garage rock and that early '70s period when blues rock gave way to heavier and denser music. You can see the track listing for the upcoming album below.

"I essentially go through hell and high water just to find these records," said Lance Barresi, who's assembled the collections along with Daniel Hall. "Once I find a record worthy of tracking, I begin the sometimes extremely arduous process of contacting the band members and encouraging them to take part. Daniel and I agree that licensing all the tracks we're using for Brown Acid is best for everyone involved."

Barresi said there's no sign of the series – which adds two volumes to the catalog each year – winding down anytime soon. "There's a long list of songs that we'd love to include," he noted. "But we just can't track the bands down. I like the idea that Brown Acid is getting so much attention, so people might reach out to us."

Brown Acid: The Thirteenth Trip is available for preorder now.

'Brown Acid: The Thirteenth Trip' Track Listing
1. Max, "Run Run"
2. Ralph Williams, "Dark Street"
3. Geyda, "Third Side"
4. Gary Del Vecchio, "Buzzin'"
5. John Kitko, "Indecision"
6. Bacchus, "Hope"
7. Master Danse, "Feelin' Dead"
8. Orchid "Go Big Red"
9. Dry Ice, "Don't Munkey With The Funky Skunky"
10. Good Humore, "Detroit"

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