Well, its not perfect, but its better than the original "sound":
VLC startup/cmdline parameters (windows: start -> execute -> cmd.exe, switch to your vlc directory and run the following line):
vlc --audio-filter param_eq --param-eq-f1=233 --param-eq-f2=466 --param-eq-f3=932 --param-eq-gain1=-20 --param-eq-gain2=-20 --param-eq-gain3=-20 --param-eq-lowf=100 --param-eq-lowgain=15 --param-eq-q1=10 --param-eq-q2=10 --param-eq-q3=10
Still missing one Frequency (1864hz) because VLC only supports 3 EQ parameters.
EDIT: Gets somehow better if you also lower 1ghz and 3ghz frequencies in the graphical 10-band equalizer.
With "real" software you can get much better results:
http://www.surfpoeten.de/tube/vuvuzela_filter
Tracked: Jun 17, 13:33
Tracked: Jun 17, 13:36