I'm using the Stereo Imager on Ozone
All in mono below 100hz, a bit wide for the mids and the highs a lot too
I never understood when people say that, is that happening real time , wouldn't it sound hollow on the mids/high
No man not at all...it actually makes the thing sound really tight. And it doesn't sound "hollow" or something on the mids/highs, cause you are only affecting the frequencies below a certain threshold.
I use a free plug-in called A1StereoControl and it works well, during the mastering I mostly use it to expand the whole thing just a tiny bit (like 115%) and I use it to automate between a wider and narrower stereo image in the course of the track.
It also has a built in "mono maker" for the subs, you can even set the threshold between something like 20hz and 500hz. Awesome thing especially for the price.
All the best,
Artless Venture ♢