To call an album avant-pop is usually a cue for people to start running as far as possible towards middling indie music. But before you dig out your iPod and retreat into the comfort and security of a Mumford & Sons album, I should tell you that Glynnaestra - the second album from English experimental duo Grumbling Fur - demands your attention. Daniel O'Sullivan and Alexander Tucker have crafted a beguiling, detailed and wonderful album that rewards with every listen somehow manages to balance accessibility and down-right weirdness.

This is Grumbling Fur's first album recorded as a duo. Their debut album, Furrier, also featured Antti Uusimaki, Jussi Lethisalo and David Smith, making the initial incarnation of the band something of a supergroup for the musical underground. Glynnaestra may feature a stripped back line-up but that doesn't mean that the album is any less imaginative. This is an album that gleefully skips between genres, mimics its heroes and, every once in a while, breaks the fourth wall. It never feels smug though, in the way that things labelled 'avant-' can be. Instead it is like a playful stage wink. This is an album with a British sense of humour.

The album opens with a director preparing his crew for the start of shooting; a modulated cello swells underneath the dialogue from various crew members. Already O'Sullivan and Tucker are breaking the fourth wall and reminding the listener that everything that follows is a performance and no matter how real it seems, it's all artifice and a fiction created by the two band members. Someone yells 'action!' and suddenly an abrasive, heavy synthesiser loop crashes into the mix. Over this comes a simple vocal couplet, choral and controlled that sings the title of the track, 'Ascatudaea', forwards and back. It's a simple performance that modulates in tempo and pitch and feels like a meditative chant taking the listener out of their drab existence and transporting them to the sonic worlds created by Grumbling Fur.

Each track brings fresh surprises to the listener. Second track 'Protogenesis' features laser gun sound effects and chipmunk style vocals common in dance music; 'Cream Pool' uses the distant song of an ice-cream van to haunting effect and, in perhaps the biggest shock on the record - one of greatest monologues in cinematic history is used for lyrics of 'The Ballad of Roy Batty'. The result is extraordinary, as the moving final speech of Bladerunner is sung over a mid-tempo guitar riff and a cello that's been processed and manipulated to create an atmospheric, drone-like backing. The layered vocals continue to help turn this song into an anthem as you can easily imagine 20,000 people, arms around one another, singing the final words of Rutger Hauer. I have to admit that when the song ended I continued humming the main vocal part, even singing the song sometimes. I had to stop myself and curse Grumbling Fur for planting such an ear-worm in my head. Devious bastards.

The influence of 1970s electronic music and experimentation is very strong throughout most of Glynnaestra - certainly during what can be called it's 'poppier' moments. 'Protogenesis' has a sound comparable to Autobahn era Kraftwerk, whilst 'Eyoreseye' and the album's title track are spiritual successors to Brian Eno's Another Green World - itself an eccentric English album that was perhaps the biggest influence on Glynnaestra. Yet it couldn't be said that O'Sullivan and Tucker merely recreate what's gone before. Throughout the album there is a sense that this is them presenting their twist on familiar genres and expanding upon the vast body of work that has gone before. Take 'Dancing Light' for example, which is one of many stand-out moments. The track is certainly influenced by krautrock and there are definite similarities to Neu in the overall presentation of the track. Reverberated vocal harmonies from O'Sullivan and Tucker are combined with a light lead synth that adds flourishes amidst the steady bass-heavy backing. Yet there is something very contemporary about the recording that tells you this firmly belongs in the present day. Maybe it's the beautifully recorded cello sections, the rhythmic structure or simply some of the extra sounds that seem to have been taken from chart-bothering pop and dance music. Like most of the album, it is a track that only really reveals itself upon subsequent listens as the myriad details and eccentricities begin to grab your attention.

Elsewhere on Glynnaestra, there are elements of folk, most notable in the acoustic guitar and vocal stylings of 'Clear Path', as well as more industrial or ambient soundscapes that characterise the instrumental numbers. If I was to pick flaws in this record, I'd have to admit that some of the more industrial instrumentals, like 'The Hound', lack the wonder and impact found elsewhere, but I'd argue that they have different purposes here. Also with each song existing as it's own separate entity there can be a strange disconnect between one track and the next, which on early listens breaks the flow of the album a little. However, once you let the album guide you and take you on the journey O'Sullivan and Tucker have created, everything seems to fit together perfectly. They even manage a few last minute surprises on closing track 'His Moody Face', an instrumental that is in equal parts haunting and menacing. It manages to reference both the ambient works of Brian Eno and down-tempo hip-hop with skittering, stumbling beats under piano loops and distant voices. In many ways it repeats a theme focused on in 'Cream Pool', 'The Ballad of Roy Batty' and, to a certain extent, present throughout the album in which found sounds become a key part of a song's construction. It's something that imbues the album with a familiarity, but it also feels like an offering - or perhaps a sacrifice. These wonderful sounds are given up to the goddess, the muse, Glynnaestra that has been created by O'Sullivan and Tucker. Throughout there is a sense that there is a higher meaning to be found within these songs and whilst I might not understand it all, I absolutely love it for the unique sonic experience it provides.

"I have seen things you people would not believe..."