Since the late 80s the Swiss trio Day & Taxi has been led by Christoph Gallio, a self-trained saxophonist who's made a virtue of restraint, both as a composer and improviser. The group's albums are peppered with short pieces that succinctly express a concise idea, and even on longer tunes Gallio and his various cohorts have emphasized economy and precision. Gallio is fluent on alto but especially good on soprano, where he reminds me a little of Steve Lacy, perhaps the instrument's most recognizable practitioner. Many musicians get a weak, watery sound out of the soprano horn, but Gallio brings a strong tone and a deeply melodic flow to it, reserving dissonance for occasional punctuation. On Day & Taxi's 2003 album, Private (Percaso Production), he's joined by explosive drummer Marco Kappeli and bassist Daniel Studer, and the three perform a lithe dance around one another, shadowing and underscoring the others' phrases without retracing any steps; on some songs they elegantly swing and on others produce a kind of lopsided funk, but the focus stays on Gallio's jagged melody lines, and every deviation or twist shoots sparks. That lineup recorded the group's most recent album, last year's Live in Shenzhen, Shanghai and Taipei (Percaso). The group's toured the world, but this is only its second Chicago gig; Gallio will bring a new lineup featuring bassist Christian Weber and drummer Michael Griener. The Astral-Terra Trapeze Unit opens. Tue 6/20, 9:30 PM, Empty Bottle, 1035 N. Western, 773-276-3600 or 866-468-3401, $6.