Felix Meritis, located in central Amsterdam, is west Europe's oldest concert building. One of its concert series for fall 2011 is "News from the Front - 250 years of 'modern' music", offering performances by three renowned ensembles: the Van Swieten Society, the Ives Ensemble and the Asko Chamber Choir. On a wintry tuesday evening I cycled to Felix Meritis to witness the Ives Ensemble playing 'Piano, violin, viola, cello' (1987) by Morton Feldman (1926-1987). The Ives Ensemble was founded in 1986 by pianist John Snijders to perform unconducted chamber music from the 20th and 21st century.

Feldman is one of the most significant names in 20th century classical music. His work was shaped by the experimental New York School of composers and the New York arts scene. A friend of avant-garde composer John Cage, he met artists like action painter Jackson Pollock and abstract painter Philip Guston, with whom he became close. Feldman drew inspiration from 'abstract expressionism', a raw and rebellious artform that put New York City at the center of the western art world after World War II. Works from this movement expressed an impulsive directness, rather than a chronologic story. The same can be said for Feldman's compositions.

Cage encouraged Feldman to compose purely by his intuition. This mindset allowed Feldman to oppose common systematic approaches to composition, like the 20th-century twelve-tone movement. In Feldman's quest to 'free' music he became a pioneer of indeterminate music, writing scores that allowed the performing musicians to improvise with rhythm. Later he abandoned the indeterminacy concept because he thought it freed the musicians rather than the music itself. He started to approach things differently, writing compositions consisting almost completely of interchangeable parts, like he was weaving a tapestry of music. It was no coincidence that Feldman collected Anatolian tapestries.

Feldman became a composer with an idiosyncratic style and a subversive work ethic. He was, according to himself, not interested in making music for a specific audience. He felt a composer had no responsibility towards his audience, therefore he did not expect to build up a fan base. But it finally happened anyway, with even his six-hour piece String Quartet No.2 (1983) attracting an audience.

The piece I went to listen to, Piano, violin, viola, cello, hails from Feldman's last period, in which he returned to standard musical notation. It was initially written for the Dutch Xenakis Ensemble to be played at a 1987 festival for new music, Festival Nieuwe Muziek Zeeland. It became Feldman's last piece, as he passed away that same year, at the age of 61, after fighting against pancreatic cancer.

The composition is fueled by a lingering juxtaposition of calmness and mystery. It delivers a tranquil but dark atmosphere spread out over 80 minutes. Its constant calmness evokes a sense of meditation, but every moment also holds an element of disturbance or excitement to keep your feet on the ground. The piece makes you feel as if you are secretly exploring an unknown network of beautiful corridors. Feldman carved a clever labyrinth out of an extraordinary material, giving you only a candle to explore. Whichever direction you take, you discover symmetry, repetitions with slight variations, so a subtly different light gets shed on the material constantly. In the end you leave the labyrinth the same way you entered it. It was the journey that counted, not the direction or the destination.

Feldman composed the piece with a somewhat minimalist approach, leaving musical parameters like tempo and dynamics unaltered throughout the piece. He did this to make the piece seem to last forever, like the patterns of a calm sea stretching out to the horizon. Most of the time during the performance I wanted the piece to last forever. Time seemed irrelevant as I was bathing in the sound without a care. There were a few moments in which I lost my concentration and tried to force myself back into it. It wasn't until I let all my thoughts go that I could listen effortlessly again. It didn't surprise me though that it took me a bit of effort to stay in the same mood for 80 minutes.

A little (inaudible) metronome was sitting on the piano of pianist John Snijders. After the show he explained that he looked at it every now and then to check that his ensemble did not deviate too much from the desired tempo, as that might stretch the piece considerably. The main pulse of the piece remained at a slow 80 beats per minute. If you would clap along to the composition you would do so every 1.3 seconds, and you would notice that the instruments seem to build their own varying rhythms around this pulse. The Ives Ensemble delivered a seamless flow of slowly interweaving patterns. Piano and string trio bounced sounds back and forward between each other, slowly shifting their timings.

Piano, violin, viola, cello's main building blocks are full and often dissonant chords. They require sensibility and stability to be conveyed in the mysterious and outstretched atmosphere that Feldman intended. The ensemble played in the exact dynamic range where the piece feels optimally thrilling. Every now and then, functioning almost like a cadence, Feldman replaced the piano chords with a slow arpeggio or a small melody reminiscent of a pattern in Debussy's Des Pas Sur La Neige. The violin, viola and cello were played in very precise manners by the Ives Ensemble string trio, where the players lifted their bows from the strings after each note. Feldman often used the same notes, even at the same time, but he gave every note a different character by using a variation of string instrument playing techniques, like harmonics.

I found that the acoustics of Felix Meritis contributed positively to the sound of the Ives Ensemble. The piece's soft vibrations reached every corner of the oval space and the instruments balanced well together. Rustling and shuffling noises from the audience made me realize how subtly soft the piece was actually played. Something got dropped on the wooden floor quite loudly and to my surprise that hit blended into the piece quite well. A striking example of the ambient quality of the music that influences space more than time. But the piece was mutilated when a constant chatting coming from outside of the concert hall became audible. It made it painfully clear how crucial the silent moments in this composition are. At some point during the composition an amusing scene unfolded when a sound engineer slowly opened a large door on the balcony and tiptoed towards his desk. His slow movements in combination with the mysterious music made it look like he was acting the role of a thief in the night.

I am very thankful to have been able to experience this piece live. I believe that the Ives Ensemble delivered the music as it was intended. The piece is fully available on the ensemble's Soundcloud page, but I recommend that anyone interested in a slowly moving and mysterious experience should hear it live: it adds even more depth to this masterpiece by Morton Feldman.

I discovered Feldman's music through experimental/minimalist electro-acoustic composer Murcof (Fernando Corona), who sampled Feldman on his first album Martes. Murcof used Feldman's unique textures and built new melodies and rhythms around them. Silence plays a crucial role in the works of both Feldman and Murcof.