a tow treatment section for forming a flat filter web from fibrous tow, said tow treatment section having an outlet through which the formed filter web is fed;

a forming section for forming the filter web into a rod-shaped material, said forming section including a trumpet guide through which the filter web fed from the tow treatment section is passed so that the filter web is gathered up into the rod-shaped material;

a wrapping section for receiving the rod shaped material from said forming section and wrapping the rod-shaped material in a paper web to form a filter rod continuum, said wrapping section having an inlet for receiving the rod-shaped material from said forming section; and

a scatter section arranged between said tow treatment section and the trumpet guide of said forming section for scattering a granular additive evenly over the filter web, wherein

said scatter section includes

a reference level line connecting the outlet of said tow treatment section and an inlet of said wrapping section,

a scattering position located near the outlet of said tow treatment section for scattering the additive, and

a flat plate-shaped web guide arranged on the reference level line or above the reference level line and extending from downstream of the scattering position up to the trumpet guide, and

said web guide bears the overall lower surface of the filter web and guides the filter web while the filter web is transported.