A hard disk assembly (HDAs) that include a tuning data memory at least including tuning data regarding the HDA. The HDAs may lack an internal disk controller, but rather may communicate the tuning data and/or other HDA-specific data (e.g., firmware, certification data, etc.) to a reader device comprising a disk controller. In this regard, the reader device may coordinate with the HDA once the tuning data is received to operate the HDA to perform TO commands in response to commands received at the reader device from a host. In turn, upon failure of an HDA, a new HDA may be swapped into place to communicate with the reader device. Because the HDAs may lack onboard disk controllers, the cost and complexity of each HDA may be reduced.