I believe all the Velodyne Digital Drive Plus models are rated well below 20 Hz +/- 3dB.
I replaced a single Digital Drive 18 with my third generation of Velodyne, two Digital Drive 12 Plus in my two channel system. It's a largish room with a vaulted ceiling. The two smaller subs added to the sound stage as well as the rooms bass nodes have lessened.
I replaced a single Digital Drive 18 with my third generation of Velodyne, two Digital Drive 12 Plus in my two channel system. It's a largish room with a vaulted ceiling. The two smaller subs added to the sound stage as well as the rooms bass nodes have lessened.