It takes instruments, amplifiers and a volume knob to be a heavy band. It takes all those things plus skill and ambition to be a heavy band that’s interesting.

Two of Bend’s most interesting and ambitious heavy bands are teaming up for what should be a terrific show tonight at Mountain’s Edge in Bend.

Warm Gadget is the newer of the two bands on the bill, a quartet that deftly mixes sludgy quasi-metal and industrial noise with experimental electronic touches. They’ve played sparingly over the past few months, but the reviews are resoundingly positive.

Tentareign, on the other hand, has been on the local scene for a few years, though they’ve been scarce recently. That’s because they’ve been in the studio, and their MySpace promises not one but two albums this year. Exciting! I don’t know what they’ll sound like, but past Tentareign work could be described as thunderous, hyper-skillful prog-metal.

There are a lot of shows in town this week, but in my mind, this one’s a can’t-miss.

Tentareign and Warm Gadget ; 9 tonight; $3; Mountain’s Edge bar, 61303 U.S. Highway 97, Bend; 541-388-8178 or www.myspace .com/tentareign.