Depends on the capacity of storage drive you attach to it, which could be an internal 2.5" SATA SSD or hard drive (BDP-3), an external USB drive or Network Attached Storage (NAS) unit.
As an example, a 2TB drive could hold an average of ~ 3000 1-hour albums in uncompressed format (44.1KHz/16bit) or up to twice that amount in a compressed format such as FLAC.
Steve