Five chamber works by James Opstad, played by Apartment House, the GBSR Duo & clarinettist Heather Roche. James Opstad is probably better known as the double bassist with Apartment House than as a composer. But this should change with this release, the first CD of his music as a composer. 
Five beautiful pieces tracking the evolution of Opstad's work as it moves from textural electro-acoustic music to pieces exploring the layering of instruments playing at slightly different tempi:

"Eluvium marked a bit of a turning point for me. In the period prior to writing it, I had been exploring electroacoustic music and the use of live electronics. This had led me towards writing music that was very sound based. I was starting to long for a return to using pitch in a more deliberate way–even just the act of writing one note after another. I was still interested in using technology but was more keen on how it could be used within a primarily acoustic context.

Eluvium involves a live feedback process in which the clarinet and tam-tam are recorded in real-time. The recording is then played through a speaker that is placed behind the tam-tam. This process repeats throughout the piece, leading to an accumulation of resonant frequencies. The sound-world does change considerably but it’s all as a result of this process and the way in which the clarinet part is constructed. So, what I was looking for was this gradual transformation, but also a feeling of erasure. There’s this sense in the clarinet part, resulting from the way that the tempi are alternated and layered, that it sort of wipes itself out. This is heightened by the blurring effect created by the tam-tam, which eventually engulfs the clarinet altogether. I see this piece as a precursor of the rest of the music on the album, not only because of a renewed focus on pitch, but also because of the layering of different tempi. This went on to become a recurrent feature of my work."