The Bel 2120B is designed to allow 4 audio signals to be selected, modified and then routed to 4 outputs. Input signals may be derived from analogue, AES or SDI (any group) sources. Output signals provided are analogue, AES and SDI (any group). Headphone monitoring is also available on the front panel. The unit can be controlled from front panel switches or remotely via an RS 422 serial port. Auto/Manual 'Bypass' is provided as well as a 'Lock' function.

Two main modes of operation are possible:

Matrix: Each input can be inverted and its level adjusted in 1dB steps [+10 /-30dB / Off], then routed to any output.

Mix: Each input can again be inverted and its level adjusted but any combination of inputs can be routed to any output.

In both modes of operation all parameters/set-ups are displayed graphically on the LCD and may be stored in user defined memories.

The simultaneous output of audio in all forms enables the Bel 2120B to be used as an SDI, AES/EBU and an analogue audio Shuffler as well as being able to Mux and DeMux to and from SDI. Simultaneous conversion between all three formats is available.