Bristol-via-London duo Emptyset have announced that they are to release a new EP via the Subtext label. Entitled Material, it's a triptych of sorts, containing recordings from three site-specific installations that the duo worked on during winter 2012, including their Sounding Space installation at London's Ambika P3 concrete bunker, and a commission for Tate Britain to record at the Trawsfynydd nuclear power plant in North Wales.

The idea was seeded by the duo's Medium EP, released last year through Subtext. It found them setting up a huge soundsystem in an unfinished Gothic mansion in the Cotswolds, projecting sub-bass and higher frequencies through the building and recording the results. The idea, as Emptyset's James Ginzburg explained in an interview with the Quietus last year, was "just setting up a sound system and microphone array and improvising with the feedback within that space, and allowing the architecture to impose its own dynamic set of circumstances onto what we'd pre-prepared. So for us that project was almost about - how do you take something out of the controlled environment of the studio, where there is an element of unpredictability but it's always contained within a set of constraints - [and] go into that environment with something that's a completely uncontrolled process."

In the time period since, they've done three other similar installations, using a sound system to project frequencies through architecture and recording the responses of the space around them. One was an extended installation in the Ambika P3 bunker beneath London's Architecture Foundation. Following that, the duo were commissioned by Tate Britain to produce a film installation using the same methods at the decommissioned Trawsfynydd nuclear power station - the film, premiered at the Tate a couple of weeks ago, matched grainy and unsettling footage of the empty power station with crushing blasts of bass and long trails of echo. Finally, they recorded a similar piece in Chislehurst mine in Kent.

Material gathers together excerpts from these projects. "Collectively the recordings provide an immersive document of these three locations, crafting a unified exploration of structure, material and sound," says the text accompanying the EP's release. The idea was to "explore the relationship between space and the fundamental properties of sound, applying extreme bass, noise and feedback as means of extracting the essence and sonic signature of these unique sites. Across the recordings there is a focus on the nature of sonic decay, as each space imparts its signature reverberant characteristics to the signal, ranging from detailed noise reflecting across sheer concrete surfaces to low frequency sonics tunneling through subterranean earth."

Material will be released on vinyl on March 18th, and on digital on March 25th. Its tracklist runs as follows:

'Trawsfynydd Nuclear Power Station - Snowdonia, Wales 17.12.12'
'Ambika P3 - London, England 12.12.12'
'Chislehurst Mine - Kent, England 02.11.12'