Steve regarding the soft brush have trimmed down all the bristles and how much have you trimmed off the bristles , Also what did you use to trim bristles down . Thanks Mike
I cut about 20mm ish off all the bristles ( the inner 2 rows perhaps slightly more )
I used a pair of kitchen scissors to cut the bristles down, just find something the correct thickness, like a ruler, an use it to cut along.
Its a trial & error thing, find an old brush, give it a trim and see if you like it