The long post-jazz festival lull comes to an end this weekend with a pair of duos blowing in from the Windy City. Tomorrow evening at the Casa del Popolo, Triage, led by alto saxophonist Dave Rempis, make their first ever Montreal appearance. And then on Sunday, the three-saxophone powerhouse of Ken Vandermark, Mats Gustafsson and Peter Brotzmann, together known as Sonore, will unleash a storm of sound at El Salon.

The 29-year-old Rempis is excited about bringing Triage to Montreal. It’s the second stop of a two-week tour of the East Coast and Midwest in support of the group’s fourth album, American Mythology, out this month on Okka Disk. As a member of the Vandermark 5, Rempis knows Montreal well, and he calls the Casa one of his favourite places to play in North America.

The sound of the trio, which also includes bassist Jason Ajemian and drummer Tim Daisy, owes much to the European free improvising tradition, with a lot of space for each musician to develop within a loose structure.

As Rempis puts it, "The focus of the group is on improvising. We try to figure out ways to play compositions in different ways, to mould the compositions."

The ethos is part of an ongoing process that began with the group’s formation in 1999.

"In the last year, we have been moving away from playing distinct compositions and into longer improvisations," Rempis notes. "We’re bringing in material that we’re familiar with but not in a predetermined way."

The interaction among the players is not as tight as one might find in, say, the Vandermark 5. Those who have been following the V5 will not be surprised to hear that it is Rempis’s own playing that is the focus of Triage, and that’s a good thing. He is rapidly developing an impressive solo voice on the alto, and one wonders if Triage will be long confined to the smaller venues.

Triage is at Casa del Popolo, Sept. 3, 9 p.m., $8 advance, $10 at the door. Sonore is at El Salon, Sept. 5, 9 p.m., $15 advance, $18 at the door. $21 advance for the two shows. For info call 284-3804.