Triangular Progressions: heavenly computer music filled with magic potential

Mattias Petersson, Triangular Progressions, Switzerland, Hallow Ground, vinyl LP (2023)

Originally from a classical piano background, Stockholm-based Mattias Petersson has been active as a composer and performer of computer music, both singly as Codespira1 and as part of the duo There Are No More Four Seasons with violinist George Kentros. Currently Petersson is an associate professor at the Royal College of Music in Stockholm where he also obtained a diploma in electro-acoustic composition. With a CV like that, it’s a surprise then that he hasn’t featured on Swiss label Hallow Ground earlier along with fellow Swedes like Maria Horn and Mats Erlandsson. Never mind, “Triangular Progressions” is Petersson’s debut with the label, a work which he composed, recorded and mixed over 2019 to 2021 during the global pandemic lockdowns.

Written with the use of free open-source SuperCollider software, “Triangular Progressions” is based on Petersson’s fascination with a magic number triangle that he developed during his early compositional studies and which he has used as the inspiration and foundation for several compositions over the past 20 years. Petersson’s investigations into the harmonic progressions within the magic number triangle have resulted in a work of an unearthly, spiritual quality and (despite its slow minimalist style) filled with magic potential. Although this is 100% computer music, it doesn’t sound like computer music at all: it has a spacious three-dimensional quality that draws the listener into its depths and the long, drawn-out tones seem very much like church organ music, albeit of a radiant lightness not usually associated with church organs.

Understanding the mathematical underpinnings of this work isn’t necessarily to enjoy it as a relaxing deep-listening experience that helps expand the mind and allow it to wander at will in a serene environment filled with its own light. The music sometimes sounds as if it’s going a bit off-key at times but these unexpected moments are like little bolts of lightning that wake up a slumbering brain. Despite the long droning notes, the music never sounds cloying or cute. Though it’s hardly party music, this recording does repay the time spent listening to it by opening up other-worldly dimensions you didn’t know existed within your head.