Brushing too hard for my gums. How about with soft bristles Braun or P & G?

The Pulsonic toothbrush (basic unit) was once given to me. I have now bought later for the first time brushes. I felt the brush as something hard. After the "plastering" the feeling is a little better. Unfortunately, I told my tooth Pflegerinn now that these brushes are too hard for my gums and I better should use soft. Because there is no alternative tempers for Pulsonic, the toothbrush is, together with three unused Austeckbürsten, unused hiking in the closet.

Beautiful waste of money in both senses because the expensive replacement brushes are even. How about with soft bristles Braun or P & G?