Finally got a chance to move one of my subs to the OFFICE and Bedroom System (15" Velodyne) and it is a WINNER.
I am now using a pair of B&W standmounts and now the 15" Velodyne.
it blends perfectly and adds a complete new dimension to the already good B&W mains.
I used a summing Y-adapter, and it was good to go
Little Jethro Tull (AguaLung) playing now via Bluetooth, and the bass line is clear and melodic.
I don't think my HT system will miss the Velodyne, since I have 7 additional subs still in it.