Stones Throw message board hosts a weekly beat battle which has been going on for years. It's completely user-run. Hundreds of hip-hop producers & beat makers have come through over the years, including Jonwayne, who made this beat in last week's round.  

Jonwayne: "I used to participate 4-5 years ago … I took a look at this week's samples and liked the selection. Inspired me to make this lil 20 minute microwave beat … I'm upping this to encourage some of you producers to take a look at what they do every week and get involved."

THE RULES ARE SIMPLE. ANYONE CAN JOIN. Each Saturday a sample is posted in the Beat Battles forum for beat makers to work with any way they choose. Beats are posted on a Soundcloud group by Wednesday. Voting takes place on the board Thursday-Friday. The winner chooses the sample and sets rules for the next battle.

Here are the rules, as written over the years:

The latest round is Beat Battles #342, which began Saturday, Sep. 21:

Here's a few others from last week's beat battle #341.