Sweden’s Åke Parmerud has assembled four acousmatic works dating between 1990 and 1995 on a must-have collection of out-of-print recordings. (Acousmatic is an electroacoustic subgenre composed for presentation with speakers rather than live instruments.)

These powerful, sometimes disturbing recordings all date back to the mid-1990s. Thematically and artistically, each has maintained extraordinary relevance.

Grains of Voices came out of an invitation to produce a piece of music drama for Swedish Radio. “I decided to make a composition concerning the human voice, its symbolic implications and its musical applications,” writes Parmerud in the album’s notes. “The sound of the voice is a striking symbol of the unity of mankind.”

He recorded the voices in-person, inviting speakers and singers to share anything they wished. “This way I did not (with a few exceptions) control what went into the composition, only what came out.” Parmerud describes the 31-minute work as “a multilayered, cross-cultural hybrid piece of sonic art.”

Jeux imaginaires (or Imaginary Games) was inspired by the 1992 World Chess Championship match between Anatoli Karpov and Garry Kasparov. Aside from a middle section that sounds like a frenetic game of park chess, the work is a study of the parallels between the game and composing music.

“Every night after ending my composing session in the studio I played the game (or maybe only a few moves) on my portable chessboard. Apart from it being a nice way to turn my attention away from pure musical problems for a while, I found that playing the game made me more and more aware of the likeness between chess playing and composing. … [P]laying the game as a small ritual every night released new musical ideas and composing energy without necessarily creating detectable parallels between the music and the game itself.”

Les objets obscurs (Hidden Objects) is a musique concrète piece in four parts. Or more precisely, a meta-musique concrète piece.

We’re presented with riddles (in French) having to do with the source of the sounds used. The answers are offered musically. “In the end of the last movement the ‘solution’ of all the riddles is presented. These answers, however, set up a new ‘inner’ riddle, to which no answer is given.”

Finally, Alias explores “the duality of outer and inner existence, here interpreted through the life, music and destiny of the Renaissance composer Carlo Gesualdo da Venosa (1560-1613).”

Gesualdo is a controversial 16th/17th century figure. As a composer, he’s considered to have been hundreds of years ahead of his time. As a human being on the other hand, he’s remembered for the gruesome double murder of his wife and her lover.

“ Alias is not, however, an attempt to illustrate the shifting identities of Gesualdo,” writes Parmerud, “but is rather, in a wider sense, inspired by thoughts on the relationship between the artist and the work of art.”

That being said, it’s difficult not to let the mind wander over the course of these two dramatic movements. Like the others on this important new compilation, it is a powerful work.