I've used 601S3's for over a year and the bass was just excellent. Although they did have a slight midbass hump, to give the impression that they have more bass than they actually do, I found them to pretty good speakers.
They're nothing short of bass, and since seeing you're using good stands (I used mine on Nexus 5, which I though where slightly better in bass response, but only just!) I think you need something totally different to satisfy your needs.
MA BR2's I also considered when I wanted to upgrade, but to my ears the 601's totally blew these away. The BR2's sound veiled and muddy in comparison, and the bass was spotty and not at all acurate. You could consider RS1's which I thought were I big step up from the BR2's.
I've also listened to the 685's several times, good speakers they may be, I couldn't justify the extra outlay over the 601's. They're not th t much better, but maybe you do like them.