If it weren't for Manfred Eicher and his ECM (Editions of Contemporary Music) record label, a group like Double Image might go unrecorded. The quartet, which began a three-night engagement at the Cellar Door Thursday night, explores the qualities of mallet percussion instruments: The tones and textures they produce and the tapered silence they give rise to.

It's precisely the kind of inquiring music Eicher has championed for some time now with varying degrees of success. Fortunately Double Image treats their music more as an experience than an experiment, avoiding the precise but dispassionate playing common to some ECM recordings.

The band derives much of its inspiration (as well as its name) by juxtaposing the sounds of the marimba and the vibraphone. Over the course of five extended pieces Thursday night, David Friedman and Dave Samuels traded contrasting solos, exchanged melodic and rhythmic functions, and frequently merged in swelling harp-like resonance. They fashioned from oriental motifs or subtle Latin rhythms lengthy improvisations that were made all the more interesting by bassit Ratzo Harris' jagged lines and drummer Michael Dipasqua's generous cymbal sprays. They certainly deserve to be heard by a larger audience than the merger one on hand Thursday for their Washington debut.