Ligeti meets AI with Salonen conducting the San Francisco Symphony and Chorus

Video still from Ligeti: Paradigms. © Courtesy of the SFSO

The latest instalment in San Francisco Symphony’s online series with their Music Director  Esa-Pekka Salonen takes us deep into the astounding realm of the György Ligeti oeuvre. Guided by a riveting fusion of top-class musicianship and cutting-edge AI, Ligeti: Paradigms yields to the next level of online presentation. 

Available for streaming on the orchestra’s SFSymphony+ platform, the production features Salonen conducting the SFSO and Chorus in performances imbued with visual design and spatial audio devised by the AI team, led by media artist Refik Anadol and SI Symphony Collaborative Partner and roboticist Carol Reiley. For Salonen, Ligeti: Paradigms is the next step in a continuum begun with Laila (2019-20), his interactive opera collaboration with Paula Vesala et al. at the Finnish National Opera, as well as his SFSO tenure launch, Throughline, presented online in November 2020.

There are three Ligeti scores involved, in spectacular performances, all written between 1966 and 1973. Each of the three works are rooted in the idea of micropolyphony, where intricate musical fabrics arise from dazzlingly detailed contrapuntal writing, diving rise to a fascinating sonic paradox; textures that are buzzing with activity and quasi-static at the same time. 

We get off the ground with Lux aeterna (1966) for mixed choir a cappella, best know to wider audiences from its (initially unauthorised) appearance in Stanley Kubrik’s 2001 – A Space Odyssey (1968). Coming in the heels of Ligeti’s astounding Requiem (1963-65), Lux aeterna is certainly one of the most captivating choral scores of the postwar avant-garde. 

Composed for a sixteen-part mixed chorus, Lux aeterna is a feast of contrapuntal writing. Its complex web of interwoven musical lines results in slowly moving, cloud-like formations of spellbinding harmony and colour. True to its title and text, derived from the Missa pro defunctis, the score comes off as the most thorough sonic representation of the idea of perpetual light, floating aloft outside time and space. Despite its relatively brief, eight-minute duration, Lux aeterna seems to convey a lifetime and beyond. 

Presented in Dolby Atmos binaural audio, especially designed for headphones, the sixteen-part polyphony of Lux aeterna is given in stunning spatial mix, based on AI rendition of the awe-inspiring performance. Sounded within mental cathedral of the listener, Ligeti’s shape-shifter-of-a-score gets a wondrous workout, one to enamour the mind and soul. 

The dream-like visual realisation combines performance material with abstract spatial imagery of shapes and colours, rotating in gradual motion, in accordance with the performance.    

Video still from Ligeti: Paradigms. © Courtesy of the SFSO

Scored for twelve-part string ensemble, divided into two groups with different tunings each, Ramifications (1968-69) takes the ideas of micropolyphony and microtonality on whole another level. Instead of blending the instruments together into single sonic entity, the parallel motion of two ensembles, tuned a quarter-tone apart from each other, gives rise to two contrasting musical strata, bouncing together in order to create invigorating ambiguities in sound. 

Cast in single eight-minute movement, Ramifications is an enthralling work, one to encapsulate the listeners full, undivided attention. There are astounding colours at play, as the musical fabric is unveiled in time. Here too, Ligeti shuns away from discernible melodic and rhythmic patterns, while focusing on the seemingly endless timbral variety arising from the clashes of tunings.   

A terrific rendition from the San Francisco Symphony string players and Salonen, awash with minutiae detail and tactile nuance, the performance is visualised with ever-evolving tapestry of the universe, derived from the entire open source library of photography taken by Nasa’s Hubble telescope. Re-iterated and blended together by algorithms, these shifting celestial perspectives come off analogous to the ambiguity inherent in Ligeti’s score, giving rise to sequences of exquisite, multi-modal sensations. 

Vocal and instrumental lines are joined in Clocks and Clouds (1972-73), one of Ligeti’s absolute masterpieces, scored for twelve-part female choir and an orchestra of triple, quadruple and quintuple winds, two trumpets, metallic percussion, two harps and lower strings. 

While residing in the Bay Area in the early 1970s, Ligeti came across with the music of Terry Riley and Steve Reich, and was intrigued by the similarities between their seminal minimalist scores and his own micropholyphonic writing. These findings were channeled into a compositional process resulting in Clocks and Clouds

As suggested by its title, there are two kinds of musical processes at play. First, there are superimposed, phased-out, pulsating patterns, somewhat akin to those of Reich and Riley, and then then there are gorgeous, static, cloud-like formations of harmony and timbre. These processes trade through myriad of vocal and instrumental combinations, giving rise to an ever-transforming, gradually shape-shifting sonic firmament.    

The astonishing performance is imbued with processed imagery based on internet-collected cloudscapes, juxtaposed with clear-cut rows and columns of digits, generating dynamics akin to Ligeti’s music. Combined with session footage, the visual production translates the ravishing aural imagery of the performance into a sequence of radiant tableaux, as if generated by the voices and instruments themselves, under Salonen’s invigorating direction.  

In terms of musical performances, the sheer joy of hearing Salonen’s insightful readings of Ligeti, realised in sound by the wonderful members of the San Francisco Symphony and Chorus, is profoundly inspiring in itself; let alone when presented in a context ideally suited for these three extraordinary works.

The thirty-minute audio-visual programme is primed with a short behind-the-scenes prelude, featuring interview clips with the main authors as well as footage from the sessions and post-production, putting the viewer aptly on track with the artistic vision. 

A compelling alternative to traditional concert streaming, Ligeti: Paradigms is built upon firmly-based concept, combining the adventurous with the organic, in order to provide new insight into Ligeti’s music. Tailor-made for online presentation, the thirty-minute journey is indeed a deeply rewarding one.      

San Francisco Symphony Orchestra

San Francisco Symphony Chorus

Esa-Pekka Salonen, conductor

Ragnar Bohlin, chorus director

Refik Anadol, visual design

Carol Reiley, visual design

György Ligeti: Lux aeterna (1966) for mixed choir a cappella

György Ligeti: Ramifications (1968-69) for 12 solo strings

György Ligeti: Clocks and Clouds (1972-73) for 12-part female choir and orchestra

Filmed in April 2021

Released online on SFSymphony+ on 13 January 2022

© Jari Kallio

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