The Detroit of your imagination is a city out of time, so often seen through the prism of history.

But for those with more than a passing interest in 20th-century music – whether that’s punk, soul, funk, hip-hop or techno – all roads still lead to Motor City and its mythologised heroes. And when they line the boulevards with statues of Detroit’s musical greats, a marble block will be set aside for Theo Parrish, an artist and DJ whose presence has been a constant in house and techno circles for 25 years, his influence waxing and waning while his popularity never dims.

In the UK, his longform DJ sets are the stuff of legend for a generation of ravers who had their Parrishian conversions in the dark basement of London’s Plastic People. But there’s always a new cohort clocking on to his elongated style, maybe these days turned on by one of his marathon sets for NTS Radio. For some people, Theo Parrish more or less is dance music – the bridge between Detroit’s canonised history and a newer school known for its veneration of the local, the artisanal and even the spiritual.

It’s interesting, then, that it’s taken until now for Parrish to join the DJ-Kicks hall of fame, following in the footsteps of Detroit peers like Moodymann and Stacey Pullen. Interesting, too, that this is the first mix in the long-running !K7 series to be given a subtitle: Detroit Forward. At 90 minutes long and six sides of vinyl – in this economy! – it’s an extraordinary effort in every way. The ball was obviously in Parrish’s court during the whole process: he signed all 19 tracks, exclusively made by Detroit artists, and most demonstrate the personal sound signature that Parrish has been deploying for decades.

That means plenty of groove-walking enquiries into the zone where house, hip-hop and jazz collide. Ian Fink’s Moonlight and Jon Dixon’s Wind Drifts span the gap between the live band and the dancefloor, with dreamy keys, brushed drums and the feel of an all-night jam. Whodat and Sophiyah E.’s Don’t Know and Meftah’s When the Sun Falls stomp out from the same school of P-funk that educated Bernie Worrell and Amp Fiddler. And when De’Sean Jones and singer Ideeyah get together on Pressure, their shuffle-step soul comes straight out of J Dilla’s tilted rhythmatics.

But it’s a fine line between hypnotic and soporific. Memories of Parrish’s saggy 2014 opus American Intelligence are triggered by his only contribution to Detroit Forward, a collaboration with Duminie DePorres that’s a noodle soup of woozy chords, fretboard squeak and sketchy jazz piano going nowhere at all for five minutes. Weeding out the non-believers? Other shortcomings include a funk-fusion rendering of Psalm 23 by De’Sean Jones and a dub reggae imitation from Raj Mahal.

A mix of this length could hardly fail to produce some fresh quirks. On North End Funk, Deon Jamar spins a gyroscope of interlocking melodies into a blast of conceptual cyberfunk, and the pummelling repetition of Howard Thomas’ Experiment 10 is Reichian in its commitment, held together by machine drums. Both slap. Different but no less appreciated, mBtheLight drops her distorted rap over looped vocals and spongy D-town chords on aGain (T’s Edit), while Kesswa and Nova Zaii take it weirder still on Chasing Delerium, a spirit-poem tripping on jaggedy drums and a cloud of nitrous.

There are manifold directions within this sprawling giant, which often feels less like a mix than a mixtape. Would it be fair to call it indulgent? Probably not if you can claim to have had some unifying mystical experience at one of Parrish’s endurance-length club sets. But it’s possible to feel both frustrated and rewarded by the same qualities that make Parrish a singular presence within his field. More to the point, is this really the future sound of Detroit, or a fabulous rendering of the city’s recent past? Taking the long view, those myths are still to be written.

Chal Ravens