The knob adjusts the tension of the snare wires to produce a wide variety of timbres, from totally clean sounds with the snare fully off, all the way up to a tight, cracking snare like a traditional kit drummer is used to. The snare dials into a specific spot on the head so it’s almost like the snare sound gets added to the mix of possible sounds by striking the head in the “hot spot”, while maintaining, the usual range of clean bass, mid-tone, and rim shots sounds.