Tradition and innovation have always forged strong alliances in Steve Reich’s music, and his three string quartets illustrate this perhaps more than any other genre. Presented here for the first time as a complete set by the excellent Mivos Quartet, the quartet medium is transformed into a super-ensemble of multiple groups through the addition of several pre-recorded lines, while additional layers of speech recordings and sound effects are employed in Different Trains and WTC 9/11.

The main challenges in recording Reich’s quartets are to maintain the right balance between live and recorded elements (a tricky task given the large number of layers and interplay of lines present throughout each one), adding the right amount of musical character to the speech recordings without overpowering them, and ensuring that dramatic moments and gestures are neither exaggeratedly overplayed nor underplayed.

In all three respects, Mivos have come up trumps. Several excellent recordings of Different Trains – Reich’s memorialisation of the Holocaust during the Second World War – already exist, notably by the Kronos (Nonesuch, 6/89) and Smith Quartets (Signum), and by the London Steve Reich Ensemble (EMI, 11/11). However, Mivos’s recording adds further depth and dimension to this important work. Cellist Tyler Borden and viola player Victor Lowrie Tafoya offer subtle support and characterisation to the speech samples throughout, with Tafoya’s viola wrapping itself around Virginia and Rachella’s phrases in the first and second movements. A profoundly transcendent, floating quality is imparted at the end.

More tension – and in general a grittier sound – is evident in Mivos’s rendition of WTC 9/11, Reich’s grim response to the terrorist attacks on the World Trade Center, with the ending more a cry of pain and anguish than the anger heard on Kronos’s recording (Nonesuch, 11/11). But in many ways the standout work is the Triple Quartet. With the focus now entirely on musical development, violinists Olivia De Prato and Maya Bennardo’s sweeping lines are underpinned by pulsating patterns in the first movement, while a more folkish treatment of the octatonic-like melody of the second and propulsive dancelike rhythms of the third draw Reich’s sound world closer to that of another composer who brilliantly balanced tradition with innovation: Béla Bartók.