Originally Mode’s second release, issued on four LPs in 1986, the 1983 performances of Atlas eclipticalis and Winter Music played simultaneously have always felt like a seminal point of reference for John Cage fans. Atlas eclipticalis (1961) uses chance procedures “but in relation to the traced position of the stars,” Cage writes, the resulting orchestral polyphony being equivalent to a constellation of stars. Winter Music (1957) was designed for multiple pianos and notates a spectrum between single stabbing notes and tone clusters. Cage instructs players that chords, even when too notey for 10 fingers, must be played whole and that tones beyond reach are to be sounded via harmonics. The resonant mix of struck notes ricocheting against sustained harmonics is a beautiful thing, and hearing the two works piggybacking demonstrates how unerringly accurate randomness can be.

Historically, performances of Atlas eclipticalis have been prone to insurrection and mutiny. Leonard Bernstein’s performances in 1963 created one of the biggest scandals in the New York Philharmonic’s history. Some 40 years on, however, the beauty of this music seems unmistakable. Cage indicates that its character is best realised when care is taken to produce acute contrasts of loud and soft/short and long, but there’s magic beyond this state of black and white. Going to such extremes also guarantees a robust middle ground of supplementary colliding textures and coincidences of note pattern.

There were two performances on one day: the first prodigiously fluid, with winning inevitability about the music’s direction from its first note; the second with many more awkward corners and moments where the musicians work hard to define purpose and momentum. But both are an honest response to how Cage’s demands are set up. The fact the ensemble embraces musicians with dual interest in improvisation and composition helps, giving the ensemble a potent “lived-in” feel.

Adding stimulating context to the original release are separate performances of Atlas Eclipticalis and Winter Music, and the sonorous subterranean echoes of Winter Music are brilliantly captured by Stephen Drury’s ensemble. Christmas just came early.