If you have an Avant and a BV11, both of these TVs are NL products and in essence, contain an inbuilt Essence within them.
Simply connect a NAS with DLNA to the home media source and the BVs will pipe music. Album art will be displayed for a few defined seconds and random/repeat can be selected.
if you want music in a non-BV room, then an Essence and a pair of BeoLab connected to the same DLNA NAS will give you TV independent music.
I have never done it nor do I think it is possible but I think a limitation is that BeoMusic app will not let TV sound multi room to a standalone Essence.
Finally if you want a NL capable BV and Essence in the same room, you either need connect the Essence to th BV (why would you) or have at least a pair of BLs connect to the Essence. Again, why would you?