Also from Germany is Geithain, which is an extremely well regarded audio brand in Europe. Ex-GDR, been around forever, very old school. Here are their subwoofers. They’re cardioid, so less likely to suffer boundary interference response issues therefore easier to place and get right.
Geithain has no distribution / service in the US and word is that it’s kind of a labor of love to get their speakers over here, although some folks successfully have.
Good luck with your search!