Sonifex RB-SC2 Dual Sample Rate Converter

The RB-SC2 sample rate converter is a 1U rack-mount which produces AES/EBU, S/PDIF and TOSlink optical level digital audio outputs from a balanced AES/EBU, S/PDIF and TOSlink optical level digital audio inputs.

The sample rate of the outputs can be set by an internal clock or from various external synchronizer sources.

The RB-SC2 is a high performance, enhanced version of the RB-SC1 providing the following additional features:

It supports higher sample frequency rates up to and including 176.4kHz and 192kHz.

It has 2 independent sample rate converter circuits that use a common clock source to set the output sample rate.

It has 2 optional video synchronising boards. These set the output sample rate to 48kHz that is synchronised to either an analogue video signal (RB-SYA add-On board), or an HD/SD SDI digital video signal (RB-SYD add-on board).

A special X-Lock mode allows the unit to function as a full bi-directional sample rate converter.

It has TOSlink optical digital audio inputs and outputs.

It has front panel push-button switches for all the main settings. The buttons are arranged in sets, where pressing the button advances the current selection and LED indicator.

A serial RS232 port is included so that the RB-SC2 settings can be controlled remotely. The front panel LED indicators alter automatically when using RS232 commands.

For the digital outputs, there are three push-button switches to select the sample frequency (FREQUENCY), channel status bit type (CSDATA), and sync source and mode of operation (SYNC)

The FREQUENCY button allows selection of the master sample frequency from one of 32kHz, 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz or 192kHz. The CS DATA button defines the content of the channel status bits embedded within the digital audio stream, and can be forced to either Professional Mode (PRO), Consumer Mode (CON) or to follow the mode of the input (FOLLOW).

The SYNC button is used to select the synchronisation input, from the AES/EBU sync input, the Wordclock input or, for X-Lock, the other digital input. The X-Lock synchronisation allows the unit to act as a bi-directional sample rate converter with the output of sample rate converter 1 syncing the input of sample rate converter 2 and vice versa so that they follow each other.

The application for the X-Lock mode is so that the RB-SC2 can be inserted between 2 digital devices which run at different sample rates, such as a PC recorder and a digital player. Using the RB-SC2 in X-Lock mode ensures that the 2 devices remain synchronised at all times regardless of thesample rate of the 2 devices.
The SYNC button will also select the operating mode of the unit as described overleaf. If an optional video sync board is fitted then 2 sync LEDs light together to show the active video sync.