The term "instrumental impulse" was broached by the German musicologist Curt Sachs in his 1962 book The Wellsprings of Music and expounded upon by Derek Bailey in his 1980 treatise Musical Improvisation. Sachs uses the term to describe the virtuosic nature of instrumental music, and Bailey examines its implications in regard to the practice of improvisation. To sum it up in nonmusicological terms: We play fast for the same reason that seven-footers dunk the basketball-because we can. According to Bailey, the way the improviser deals with the instrumental impulse is the most important factor in his or her work.
On Evident (482), the duo of bassist Joelle Leandre and percussionist Mark Nauseef demonstrate the rewards of patience and denial when faced with an empty musical canvas. Leandre in particular is obviously a superior technician, yet it's the sedulous manner in which both harness their virtuosity that makes this music so effective. All nine tracks begin with a sparse percussive introduction-the ping of a cymbal, the peal of a bell, the click of wood upon wood-whereupon Leandre enters, sometimes with a bravura display, yet just as often with calm consideration. The episodes then expand, sometimes with a painstaking slowness, sometimes with an impulsive rapidity. What is most striking is the musical "rightness" of the pair's choices. The instrumental impulse and the virtue of restraint are held in balance, resulting in some challenging, yet very lovely, very intense music.