The adoption of the USB 3.0 interface coupled with the use of the UAS (USB-Attached SCSI) protocol and 7200rpm hard drives means the 4big Quadra can achieve speeds up up to 245MBps, with the 2big Quadra not far behind at 210MBps.
LaCie officials say this is twice as fast as FireWire 800 (the Quadra devices include two FireWire 800 connectors).
Both models feature hot-swappable drives, aluminium enclosures and "ultra-quiet" operation, and the 4big Quadra features the Noctua cooling system for superior pressure and airflow.
The 2big and 4big RAIDs can also be used in conjunction with Wuala cloud storage.
The new models go on sale this month, priced at $599 (2big 4TB), $799 (2big 6TB), $1299 (4big 8TB) and $1699 (4big 12TB) with a three-year warranty.