Think about this. The purpose of the filter is to filter out crap from getting into the engine. If a different filter changes the noise, then it is either filtering less or more.On open intakes, does the brand of filter on the end of the pipe make any difference? I've been using an aftermarket filter from AEM, but I put the filter from IE back on it the other day and it sounds louder, which i prefer.
Louder = less filtering
Is that what you want?