Chicago Jack

Where it came from

Chicago house grew out of the Warehouse and the Music Box, where Frankie Knuckles and Ron Hardy were re-editing disco records for crowds that wanted the drums to never stop. When cheap drum machines reached the South Side, the DJs stopped editing other people's records and started making their own.

The gear was whatever was affordable secondhand: a Roland TR-707 or TR-909 for drums, a Juno-106 or JX-8P for chords, and a bass line played from the same keyboard. Marshall Jefferson famously bought his rig on credit and taught himself to program it. Almost nothing was multitracked properly and nothing was compressed the way a modern record is - the rawness is the point, not a limitation someone failed to overcome.

How it works musically

Kick on every quarter, clap on 2 and 4, open hat on every off-beat eighth. That skeleton never changes; everything expressive happens in the sixteenths around it.

The shuffle is the signature. Off-beat sixteenths land late by roughly 13 ticks at 480 PPQ, which works out to 55.8% swing. Straight sixteenths turn this into techno immediately - the delay is what makes it jack.

Bass is monophonic, square or pulse, with the filter almost shut and a fast envelope opening it a fraction on every note. Sustain sits near zero so notes never blur. Chords are held Juno-style voicings, minor sevenths and ninths, with chorus engaged for width.