Hello,
i modded my Knockout like shown on the photo
to tighten up the bass response to make my cheap
guitar sound like made of realy expensive wood.
I use .33J, others may fit.

My favourite setting in combination with the Germanium
Muff and a Neo clone is (it cleans up the sound):
Low – 9 o´clock
Dry – 8:15 o´clock
High – 13 o´clock