The invention relates to a headbox (1) which comprises a feed device (4, 5.1; 4, 5.2) feeding the at least one
fiber suspension (2), a perforated distribution
pipe plate (6) arranged immediately downstream thereof and having a plurality of channels (7) arranged in lines (Z) and columns (S), an intermediate channel (8) arranged downstream thereof, extending over the width (B) of the headbox (1) and having a plurality of means (9, 9.1) for dosing a fluid (10) in partial fluid streams (10.T) to the at least one
fiber suspension (2) in a preferably adjustable / controlled manner, the means being spaced apart from each other in the width direction of the headbox (1) and the individual means (9; 9.1) comprising a plurality of dosing channels (11) having respective dosing channel openings (11.O) and an opening center line (11.M), arriving at different levels and being connected to a common supply channel (12). The headbox further comprises a downstream turbulence generator (13) having a plurality of flow channels (14) arranged in lines (Z) and columns (S) and a headbox
nozzle (16) which is directly contiguous to the turbulence generator (13) and which has a
nozzle gap (17). The headbox (1) according to the invention has a
system pressure loss which is substantially composed of a first pressure loss (
Delta p1) between the feed device (4, 5.1; 4, 5.2) and the intermediate channel (8) and a second pressure loss (
Delta p2) in the turbulence generator (13), the second pressure loss (
Delta p2) and the first pressure loss (Delta p1) being in a ratio
ranging from 8:1 to 1:1, preferably from 4:1 to 1:1, particularly from 2:1 to 1:1.