Listening to the music of the Austrian Georg Friedrich Haas (Graz, 72 years old) is similar to climbing an Escher staircase: one is certain to move forward, but always returns to the starting point. The musicologist Bernhard Günther explained it with a revealing analogy: in conventional music, melodies, the twelve-sound scale with its tones and semitones, and metric regularity function as railings and handrails that allow us to climb a staircase without looking at the steps. Any alteration of those proportions—like the forced perspective of Bernini’s Scala Regia or the deceptive geometry of Odessa’s Potemkin Staircase—is enough to cause concern.
Haas goes much further: removes all those handles. Its main tool is microtonality, the division of the twelve sounds of the tempered scale into smaller intervals, something like going from centimeters to millimeters and from millimeters to micrometers. But what distinguishes Haas from other microtonal composers is the astonishing naturalness with which he integrates that technique into the harmonic spectrum, freeing sound from the cultural prison of the piano keyboard and letting the music breathe as nature itself does. Added to this are the beats, that physical vibration that is perceived when two notes are almost in tune but not completely in unison: a pulsation that is felt in the body before in the ear and that turns each of his works into a physical and sonic adventure.
This is how those attending Auditorium 400 of the Reina Sofía Museum felt on March 23, at the end of the ninety-minute non-stop concert by the Catalan saxophone quartet Kebyart. To close, the four instrumentalists addressed the saxophone quartet (2014) by Haas, written for the usual soprano, contralto, tenor and baritone ensemble. But they all ended up playing a baritone saxophone and cascading a terrifying spectral multiphonic sound, an ancient didyeridú sound or, if a more graphic description is preferred, the scream of a prehistoric monster. And then Escher’s staircase became literal: while the sound seemed to descend endlessly, the musicians slowly left the room through different exits, until leaving the audience alone with the residual vibration. The effect caused a standing ovation in the practically full room.
But that work by Haas does not end like that, if we stick to the score published by Universal Edition. “It is a new ending that Haas has not yet written and that he proposed to us to adopt when we worked with him,” Robert Seara, tenor saxophone of the group, clarified to this newspaper. In fact, this concert is part of the composer’s residency at the National Center for Musical Diffusion (CNDM), although a health problem that forces him to travel in a wheelchair has prevented him from being present in Madrid. The series began in November with the performance of his most famous work, In vain, for an ensemble of twenty-four instruments (2000), and has continued in Classroom 400, in January and February, with his String Quartet No. 11 (2019) y Tria ex one (2001).
Other compositions of his are scheduled in April and May, such as Anachronism (2013),“…connected out of free desire…” (1994) y Tribute to Bridget Riley (2019). But the main milestone of the residency has been the world premiere of his Saxophone quartet no. 2. In memory of James Cecil Williams (2026), commissioned by the CNDM. And this premiere has coincided with the presentation of Kebyart in the Series 20/21 cycle. If the Catalan group closed its performance with the twelve minutes of the first quartet from 2014, where Haas focuses mainly on the ostinato and timbral decomposition, in this new Quartet no. 2, which was the center of the program, confirms the evolution towards the emotional that was already indicated by that new ending of the previous one with the four baritone saxophones leaving the room.
In this new composition, Haas relies on the aforementioned beats and adds a spatial distribution of the performers in two duos located at both ends of the room, enveloping the audience in shocking sound frictions. Each of the members of Kebyart explained a work from the program in an entertaining and simple way; Víctor Serra, commenting on Haas’s premiere, highlighted the mixture of excitement and challenge that it had meant for the quartet, since it required the use of nine different saxophones – three of the instrumentalists used two and one of them used three.
The work is dedicated to his father-in-law, James Cecil Williams, father of his current wife, the artist and performer African American Mollena Williams, who died last summer. Williams was a saxophonist who played in Times Square and who was psychologically broken as a Marine in the Vietnam War.

The forty minutes of the piece handle with sonic virtuosity the possibilities of the two saxophone duos in their multiple combinations of tessituras. But the most interesting thing is Haas’s ability to hypnotize the listener by alternating passages that seem to narrate the life of his father-in-law – in one you hear a kind of deconstructed blues – with the friction caused by the microtonal beats and the spectral multiphonics, which twist as if to evoke the psychological destruction caused by all wars. Something that is fully relevant these days of the United States and Israel offensive against Iran and that agrees with the political inspiration of a good part of its catalog (remember that In vain was born out of outrage at the resurgence of the extreme right in Austria).
After a brief pause for the excellent Kebyart musicians to catch their breath, the music of Hèctor Parra (Barcelona, 49 years old) acted as a hinge towards the first Haas quartet. Striated fragments (2004) is another original piece for saxophone quartet where texture serves as sound inspiration and, more specifically, the ultra-black paintings of Pierre Soulages, in which light emanates from striations, scratches and grooves on the black oil paint. Parra translates these elements into sound through harmonics, multiphonics and changes in pressure in the air, starting from very dark and massive sound densities. The ensemble offered a masterful performance of this composition, which they included on their debut album in 2017.
And it was a great success to start the evening with the attractive arrangement of Intermissionby the American Caroline Shaw (Greenville, 43 years old), a 2011 composition originally for string quartet, although popularized in a version for small orchestra. This is heard in a sequence from the third episode of the fourth season of Mozart in the Junglewhere Shaw herself plays herself. The work was born from an audition in Princeton of the Brentano Quartet playing the transition from minuet to trio in the Quartet in F major op. 77/2 by Haydn. Shortly thereafter, Shaw became the youngest woman to win the Pulitzer Prize in Music for her Partita for Eight Voices, another example of his ability to convert traditional structures into something new through extended techniques.
The arrangement for saxophone quartet of Intermission It was performed by Xabier Casal, from the Fukio Quartet, although it has been retouched by the members of Kebyart. And all those typical string instrument techniques that Shaw deploys almost flow better with saxophones, bringing the piece closer to the sound of the 21st century. The members of the Catalan ensemble demonstrated this with a masterful use of the subtone to replace the “airy” sound of the string and the slap tongue for the dry blow of the pizzicatos, but above all because of the connection with the human voice that the saxophone has.
Series 20/21 del CNDM
Works of Caroline Shaw, Georg Friedrich Haas y Hector Parra.
Kebyart (Pere Méndez, soprano saxophone; Víctor Serra, alto saxophone; Robert Seara, tenor saxophone and Daniel Miguel, baritone saxophone).
Auditorium 400. Reina Sofía National Art Center Museum. March 23.