An acoustical impedance inducing device is created for axial insertion into the longitudinal air column of a wind musical instrument. The device includes a first annular band of first predetermined thickness and a second annular band of approximately twice the thickness of the first band. A first web interconnects the first and second bands and maintains the bands at a predetermined axial spacing. The web is formed of strips diagonally disposed between the first and second bands and defining a triangle shaped aperture between adjacent bands, with the base of the triangle being colinear with an edge of one of the first and second bands. A third annular band, twice the thickness of the second, may be separated from the second band by a second web; or the device may be placed in a tubular portion of the instrument at a location where an end of the tubular portion is spaced from the second band by the axial width of the web.