The Apogee I/O Modules are the sound and soul of the Apogee Symphony I/O interface, and represent 25 years of Apogee research & development, and design excellence. The AO16 module offers 16 channels of analog output and up to 16 channels of analog AND digital input simultaneously. Optical input accepts ADAT (16 channels), SMUX (8 channels), and SPDIF (4 channels) formats. Two RCA connectors supports SPDIF IN/OUT. This powerful module delivers Apogee's core competency and superior sounding digital audio recording.