Speaker Stand Filler
We always recommend using good quality speaker stands with bookshelf speakers, because despite their namesake, they will always sound best when supported properly - and that isn't on a bookshelf! Similarly, if your speaker stands are fillable, we always recommend filling them with one of these proper fillers. This dampens the stands (reducing any "ringing" effects you can get in metal stands), weighs them down and improves bass response as you fill them (we recommend starting by filling them stands half-way, listen to hear the bass response and then progressively increase the filler until the bass response sounds right in your room).