Ellen Arkbro's fourth album, "Nightclouds," brings together five improvisations for solo organ, recorded in Central Europe in 2023-24. More overtly romantic and introspective than her earlier works, "Nightclouds" remains firmly rooted in the rigor and precision that define Arkbro's approach. Expanding on her explorations of spatial harmony, tactility, and texture, Arkbro draws equally from sacred music, ECM-style jazz, and minimalism, conjuring a cool intimacy and a chilling tone. Her decelerated chord improvisations envelop the listener in a dark haze, while her microphone technique reveals the raw, tactile grain of the reed, placing the listener both inside and outside the sound. She evokes duets by Kjell Johnsen and Jan Garbarek, or La Monte Young and Tony Conrad's arrangement of Euringer and Harmer's cowboy song "Oh Bury Me Not." “Nightclouds” channels spiritual pathos through a rigorously restrained architecture. Following on from last year’s album “Sounds While Waiting” (W.25TH, 2024), a selection of stereo mixes documenting Arkbro’s spatial organ installations, “Nightclouds” shifts direction, focusing on immediate composition and improvisation. Elegant, simple chordal frameworks support rich, ever-changing textures; close listening demands a surrender to sustained indecisiveness. Concluding a collection of short pieces are two variations on the title track, “Nightclouds,” one a mischievous nod to British jazz guitarist Allan Holdsworth: the first recording slows and stretches a continuously modulated harmonic progression, while the brief closing version simply loops three chords. Between these pieces lie "Still Life" and "Chordalities," two short works recorded at the Temple de La-Tour-de-Peilz in Vevey, Switzerland. The second half of the album is dedicated to the following piece: "Morningclouds," a sprawling work recorded in the reconstructed Kaiser Wilhelm Memorial Church in Berlin.