It's hard to decide which aspect of the latest release from JR Robinson's Wrekmeister Harmonies project is the most important. Is it the music, or is it what the piece represents? And yes, I said 'piece' - this isn't an album in the traditional sense. It's a 38-minute long composition which raises many questions about patience and longevity. There is an 11-minute version used in the video for the piece, if you're not up to sitting down for the guts of 40 minutes to digest the full thing, but that's not an easy feat, either; to appreciate You've Always Meant So Much to Me in full, you have to give yourself to it, digest it fully, pull it apart and put it back together; you have to live with it. You either go in hard or you don't go in at all. You press play - or more specifically, you drop the needle on side A and let the record play. It's a vinyl-only release; whether experienced in physical form or via digital technology, one must put in real effort to get the most out of it.

Robinson is joined by metal musicians from his native Chicago; members of Leviathan, Nachmystium and Yakuza appear on this piece, which was first performed at Chicago's Museum of Contemporary Art last year. If you're expecting a piece full of searing, oppressive heaviness, though, you've come to the wrong place - it's certainly oppressive, but only in the way it builds at a tortuously slow pace. A single, droning chord lays the foundation for the whole thing, with fragments of melody, scattered notes and an anticipation-building, prophetic buzz of feedback all slowly seeping in and fading away. 13 minutes have passed before there's any semblance of a melody one can actually hold on to, with a gentle four-note harp ostinato taking centre stage for a while before the atmospheric drones from before re-enter, only more forcefully this time. Soon there are violins present, and all the elements of the music seem to fold in on each other, teasing an explosion of sound as the noise, along with the listener's patience, is stretched almost to breaking point.

Every single small change in the make-up of the piece feels like an event; however, that's nothing compared to the effect it has when things finally take off; 22 minutes in, the track erupts: drums thud, guitars crash, disembodied vocals howl and screech in an apocalyptic, wordless, devastatingly powerful metal hymn. Where before it was content to simply regard the abyss, it tips forward into it and is in freefall for six minutes before a sense of relative calm is restored - if, indeed, it ever really existed. From its peak, it gradually falls away, until only the four-note harp motif remains, and that too eventually dissipates, leaving a stark, bleak, complete silence. This is music that takes the listener on a journey deep into themselves; it's not something one can just sit down and listen to, because its intensity means that it must be equally as intensely focused on throughout, but it's a genuinely rewarding experience that becomes more powerful with each listen. At 38 minutes a pop, it may seem like an effort to listen to on paper, but every minute is time well spent.