SLAM's first album in seven years, 'Reverse Proceed', takes me back to Scotland. Not to recollections of the pink hills and heath that the morning train would take me through on my way back to Fort William after a Friday night out, but back to the nights spent in clubs listening to techno. I can't think of Scotland without thinking about Glasgow, and I can't think of Glasgow without thinking about the nights I spent at Pressure, the seminal monthly party SLAM put on at The Arches. This is by far the best party in Scotland, held in converted railway tunnels in the centre of the city. The space is airy and open above you, stretching up under Victorian railway lines that linked the city – which extended, through her ship building yards, steam engines and factories, out across the globe – to the enormous chamber you are dancing in, bathed in blue and white light. Glasgow Central Railway Station was once the centre of the world, one of the gates to everything else. When you are at Pressure, you are dancing beneath the centre of the world, in the original steel city.

Glasgow is a working class city; the same hard-work that characterises other former-industrial techno flash points like Detroit or Berlin. Glaswegians work hard; they have earned their weekend parties, and they are great fun to be around because they love to party hard. (It is for them, I imagine, that one of the best tracks on the album is called “Factory Music”.) Other people travel to Glasgow to party; Friday night there is as much fun as can be had in Britain, especially now that sniffer dogs are cruising the line at fabric (where SLAM have also left a considerable mark as DJs, including recording fabric09: SLAM).

Glasgow has the reputation of being a fighting city. Consequently, the police are everywhere on the streets – highly observable in hi viz jackets, relying on the panopticon of visibility to do its work, knowing that people behave differently when they are seen. Techno parties need to stay underground and out of trouble. The bouncers at Glasgow parties do a good job at keeping the partiers out of the way of the police. Glaswegian technophiles are there because they love the music, not because they want to get drunk and fight. They have worked hard all week in the ground zero of the industrial revolution. Industrial techno is their soundtrack; they are looking to escape; they are looking to explore themselves; they are not looking for trouble. They are looking for fun and cram as much energy into the brief hours that the clubs will contain, week-in, week-out. It's very regular, almost like Fritz Lang's Metropolis – and there is a reason that Jeff Mills did a soundtrack for the film.

The thing that holds the particular lives of these technophiles together in this grey and often bleak beautiful Victorian city is techno. The 1,000 people that will come to see Jeff Mills play Pressure – when the club will feel truly alive with the intensity of the predominantly-male, predominantly-straight crowd pumping all of their enjoyment into a party washed down with Tennents. It could be intense, with so many of these sweating, pale-skinned lads crammed into the same dance, happy for others to join them. But it never feels dangerous, not the way that straight angry techno clubs in Sydney can feel, fuelled with phobias and Fosters. It never felt anything other than straight lads dancing like they had to be at work early on Monday morning every Monday and who didn't give a shit as long as you were not in the way of their fun, or straight women weekly dancing off the same week and flicking their hair and sometimes keeping their eyes closed and moving like they wanted to disappear into the amazing music.

These were the first techno nights I went to, and they are still among the best. SLAM are the key to techno in Scotland. They are the lifeline to the rest of the electronic scene that keeps Glasgow closer to the centre than it geographically is. SLAM's obvious musical brilliance is as important a part of the success of Pressure as the guest slots filled by Ben Klock or Chris Liebing or every one else who comes to Glasgow to play with them. And SLAM's label, Soma, is probably the most important UK techno label: not only for their own productions – at over 400 releases, they first recorded Daft Punk, and they still put out fantastic tracks like Gary Beck's “Before the Crash”. The release of 'Reverse Proceed' is clearly a major event in Scottish techno.

There are two types of music on 'Reverse Proceed', one of the duo, Orde Meikle explains: “deep pulsating warm up and throbbing techno” [RA Exchange 207]. These are the styles that match their two Scottish residencies: Return to Mono at SubClub, where they play the pulsing hard techno for which they are renown on dance-floors the world over since the 1980s, and their monthly residency Pressure at the amazing space, The Arches, were they warm-up for international acts when not holding the floor themselves all night. 'Reverse Proceed' is a showcase of both styles.

The journey starts with “Tokyo Subway”, a hyper-modern sound with a frantic Japanese railway station voice-over setting us drift as far from The Arches as imaginable. It is this ability to dream, carried by that soft, almost aquatic sound that is heard from “Visual Capture” until “Cirklon Bells”, that sets up the gentle beginning of this album, taking us far from ourselves, showing SLAM's skill for massaging the listener into a space where the harder techno takes over, and pounds the week away. The hypnotic effect feels like the start of a good night.

'Reverse Proceed' is more than a techno album; it is a political album. If techno owes something to the context in which it is produced – if techno parties in post-industrial cities are a response to working hard all week, or being stuck in the monotony of trying to survive when not able to work now that the labour markets that used to float these industrial cities have largely dried up – then we need to think of techno parties as offering the potential of freedom for self-expression and self-exploration, combined with having as much fun as possible in as short a time. This ability to pop-up out of ordinary life and transform an ordinary space into something temporarily other-worldly is why techno is also the sound-track to free-parties and sex-parties around the world: how much fun is had depends entirely on how many sanctions are put in place. A part of this context is chemical stimulation – not many DJs tackle this issue as directly as SLAM, yet they all owe something to Sasha Shulgin's chemistry. But tucked away in the ambient drones from the Cirklon sequencer and modular synthesisers that start the album is a sound bite on the track “Synchronicity” from a podcast by Joe Rogan and Graham Hancock.

It says: “When the state sends us to prison for essentially exploring our own consciousnesses, this is a grotesque abuse of human rights. It's a fundamental wrong. If I as an adult am not sovereign over my own consciousness then I am absolutely not sovereign over anything and can't claim any kind of freedom at all. And what has happened over the last forty, fifty years under the disguise of the War on Drugs is that we have been persuaded to hand over the keys of our consciousnesses to the state. The most precious, the most intimate, the most salient part of our selves the state now has the key, and furthermore they have persuaded us that that is in our interests. That is a very dangerous situation.”

For twenty five or more years, SLAM has been the sound-track to the auto-pharmaceutical explorations of Glaswegians, and this album is set to be as well. At least, such might be inferred from the energy that would be necessary to dance like a drug-fucked puppet to “Factory Music”. The rest of the music is fantastic as well. “Cataccoustics” is a classic hard track that encapsulates the amoral vision that techno affords, pushing the listener to dance, not question. “Irritant” is, to my ears, the most interesting track on the album – the kind that would fit into a long Berghain set after it jumps from its quirky digital beginnings to a dark, droning, rhythm; it could also be a killer set beginning (if you don't have more than 30 seconds between DJs). From the relentless drive of “Rotary” we spin back to the dreamy, drony, soft sounds that let us into this album, in the final track, “Resolved”, although really there are always more questions left unanswered. It was well worth waiting seven years for 'Reverse Proceed'. It is faithful to the Glasgow parties it grew out of.

'Reverse Proceed' comes on slow, dances the partier through their trip as the tempo speeds up, and drops them off at the door as they walk out into the night. SLAM recreate a club night in their impeccable mix, imagining that one long dance that someone, somewhere is having. Listen to it like a journey – with its ambient soundscapes opening up into a continuous flow, through waves of techno to dance hard to, bringing you back to the streets of Glasgow, turfed out because the lights come on and the bouncers herd you back out into the dark, to stay out of trouble and away from the watchful eye of the law as Glasgow decides what to do at 3am. The underground is a temporal phenomenon.