Production collective Quakers -- Katalyst (Ashley Anderson), Fuzzface (Geoff Barrow of Portishead & Beak>), and 7-Stu-7 (Invada Studios engineer Stuart Matthews) -- are back after eight years with this 50-track, 50-minute beat tape titled Supa K: Heavy Tremors.

Supa K, aka Katalyst, says: "They returned to the planet to find humans reaping ecological havoc. From their arsenal of secret weapons comes Heavy Tremors: a sonic assault to help bring the world back into balance. This siege of beats targets the few who systematically pillage the planet and its resources for their own benefit. Play it loud."

Supa K: Heavy Tremors is a dizzying barrage of samples and beats, all pretty much in the '90s hip hop style. The awesome artwork is by Joe Currie, and you can listen below.

Geoff Barrow calls this "Part One" while label Stones Throw says "stay tuned for more Quakers news coming very soon."

Quakers' 2012 self-titled album featured over 40 contributors, including Dead Prez, Jonwayne, Aloe Blacc, M.E.D., Guilty Simpson, and Phat Kat. You can stream that below too.

Quakers – Supa K: Heavy Tremors – tracklist
Like A Drum
Speak 2 Me
Loud Music
Lets Get It
Life’s Highway
Flavor
Down Here
My People
It’s Here
Listen
Producer
I Know
The Gravy
Meditation
Magic
Power Struggle
Boogie Electric
Low Gear
Oh Shit
Blow Out
Spark Em
Wicked
Sucka
My Man
Sleep Talker
1967
Short Circuit
Zodiac
No Fakes
I Tried So Hard
WW3
Rain
Told Y’all
Think Positive
Lousy Odds
Heavy Tremor
It’s On
Ain’t Seen U Lately
First Light
Bust A Beat
Sparrow
Discrepancy
The Backburn
Liberation Is Near
Supa Fine
Bad Bwoy
Hang On
A Few Dollars More
A New Day
Think I’m Finished