Boss VF-1 Effect Processor

Hello every body,well i'm on the way to find ultimates sound with the 
vf,remember i send patches but in a curious mode,i thought that in pluggin 
the vf in the return of my H&K amp i must select combo amp mode ,i now use 
the power amp mode and then i accurate the setting of every patch and it 
sound maybe as good as a voodoo roctron,well i got just one problem i'm 
searching for the pure neutral in the equalizer (i don't understand how this 
work) so if someone can send a neutral position for this i probably can do 
any kind of killer sound,and specially in a live configuration,i already find 
a real killing thrash metal sound...