SONIFEX REDBOX A/D AND D/A CONVERTERS
Sonifex RB-DAC1 is a 24 bit, 96kHz, 1U rack-mounting digital to analogue converter which produces a stereo balanced XLR or unbalanced phono output from an incoming AES/EBU or coaxial S/PDIF digital input signal. A 6.35mm stereo jack headphone output with volume control is provided for monitoring. The analogue outputs have an output level control, allowing full-scale settings selectable to +12dBu, +18dBu or +24dBu. A rear panel button selects either the AES/EBU or S/PDIF input for the D/A converter and de-emphasis on the output can be enabled via DIP switch. When operating, the front panel power LED flashes whenever the unit is not synchronised to the incoming digital signal.
Maximum Output Level: +24dBu balanced, +14dBu unbalanced. Output Impedance: <50 ohm balanced, <75 ohm unbalanced. Dynamic Range: >100dB. Gain Range: Selectable 12dBu, 18dBu or 24dBu output level, ref FSD. Power source: 110-120V or 220-240V AC 10W maximum, switchable, fused, IEC Inlet, lead supplied, UK 13A plug. Dimensions: 1U, 108mm deep. Weight: 1.6kg
Optional accessories: RB-RK2 rear panel rack kit.
RB-ADDA - Basic Model, Preset Controls
Intended for use in professional applications the Sonifex RB-ADDA is a bi-directional A/D and D/A converter that converts, simultaneously, a stereo analogue signal to the digital domain and a digital signal to a stereo analogue output. There are comprehensive options for selecting clock-rates, synchronisation and format, whilst the analogue ports have facilities for level-matching. This unit has only a power indicator on the front panels. All adjustments are pre-set on the rear.
Four synchronisation modes: 'Master' uses an internal reference with switchable sample rates of 32kHz, 44.1kHz, 48kHz, 64kHz, 88.2kHz or 96kHz. 'Slave' locks to the selected digital input. 'Auto' is similar but reverts to the set internal reference in the absence of a digital synchronising input. 'Auto-lock' locks to the incoming sample-rate but in the absence of a synchronisation input, adopts the matching internal reference rate. The power LED flashes whenever the unit is not synchronised to the incoming digital signal. Switches provide for consumer/professional status-bit selection, emphasis and for the output word-length to be selected as 16, 20 or 24 bits with dithering applied as appropriate.
Connections: The rear panel has two 3-pin female XLR electronically balanced inputs and two RCA (phono) sockets for unbalanced analogue audio inputs. Level trim controls, +/-3dB, are accessible by screwdriver. The RCA (phono) inputs have a further 10dB gain incorporated. Two 3-pin male XLR connectors provide electronically balanced outputs and two RCA (phono) sockets act as unbalanced analogue outputs. Digital inputs are a 3-pin female XLR for AES/EBU, and an RCA (phono) socket for S/PDIF. A 3-pin male XLR is used for the AES/EBU output and an RCA (phono) for S/PDIF. Power is supplied through an IEC inlet, with associated fuse holder and voltage selector switch.
Controls: A push switch selects either XLR or RCA (phono) inputs. Similar switches choose either AES/EBU or SPDIF connectors for the digital inputs and outputs. Miniature switches allow 0dBFS to be produced from +12dBu, +18dBu or +24dBu inputs nominal in conjunction with +/-3dB (screwdriver) trim. Analogue outputs are switchable to the same reference levels as the A/D section. A further bank of miniature switches select status, and a screwdriver operated rotary switch selects frequencies and synchronisation modes.
Analogue audio input: +27/+17dBu maximum, 20/10kohms, balanced/unbalanced. Dynamic range: 110dB. Distortion: better than 96dB THD + N, 1kHz, ref +8dBu. Analogue audio output: +24/+14dBu maximum, 50/75 ohms, balanced/unbalanced. Dynamic range: 100dB. Power source: 110-120V or 220-240V AC, 6W maximum. Dimensions: 480(w) x 108(d) x 42(h) mm. Weight: 1.6kg.
Included accessories: Handbook, AC power cordset with plug.
Optional accessories: RB-RK3 rear panel rack kit, RB-FR1 front-panel kit
RB-ADDA2 - Enhanced Model - Front Panel Controls, 192kHz
This advanced design is based on the RB-ADDA, offering additional features, the most obvious of which is the array of controls on the front panel, with push-buttons for all the main settings.
It supports higher sample frequency rates up to and including 176.4kHz and 192kHz, has additional independent AES/EBU and Word Clock synchronising inputs, so that the A/D and D/A sections can operate independently, with the digital outputs synchronised to an external master reference clock. A serial RS232 port is included so that the RB-ADDA2 settings can be controlled remotely. The front panel LED indicators alter automatically when using RS232 commands. In both A/D and D/A sections, audio is sent to all of the outputs simultaneously.
Connections: All the features described under 'connections' for the RB-ADDA are present. In addition TOSLink sockets are provided for digital input and output. An additional 3-pin female XLR is available for an AES/EBU synchronisation input, together with a BNC connector for word-clock. A 9-pin male D-sub connector provides an RS232 port.
Controls: The buttons are arranged in sets on the front panel, where pressing the button advances the current selection and LED indicator. The 'A/D Source' push-button is used to select from either the balanced or unbalanced stereo analogue inputs and this push-button also defines the input level for full scale digits at one of +12dBFS, +18dBFS or +24dBFS. These values can then be fine-tuned by using the pre-set potentiometers on the rear. For the digital output, there are three push-button switches to select the sample frequency, bit-depth and status bit modes. 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 'Bits' button sets the output bit-depth as one of 16, 20 or 24 bits, and the 'CS Data' button defines the content of the channel status bits embedded within the digital audio stream. The status bits can be forced to either professional or consumer mode or to follow the mode of the input.
The 'Sync' button is used to select the input, from Word Clock, AES/EBU or the D/A input, and also the mode of the digital output. The A/D section of the RB-ADDA2 operates in the same four modes as the RB-ADDA: In 'Master' mode additional clock rates are available at 176.4kHz or 192kHz. When operating in sync modes, the SYNC button flashes whenever the unit is not synchronised to the incoming digital signal. In 'Slave' mode the unit is synchronised to an external source, or to the TTL level word-clock. The 'Frequency' LED will indicate the synchronised sample frequency and if no sync is present, no output will be generated. In 'Auto' mode the unit is synchronised to an external source, using the digital audio sync or D/A input signal from which the clock signals are stripped, or to the TTL level Word Clock. If no sync signal is present the unit runs from the onboard master clock at a rate selected by the front panel control. 'Auto lock' mode operates like the auto mode except that if no sync signal is present the unit will run at the closest master clock rate to the last locked incoming signal. The 'Frequency' LED will indicate the synchronised sample frequency.
The D/A section has one 'Source' push-button which selects the input source from AES/EBU, S/PDIF or TOSlink optical and also sets the analogue output level to be generated for full scale digits, +12dBFS, +18dBFS or +24dBFS. There are internal level controls for fine tuning the analogue output gain adjustment. If no digital audio source is present, the 'D/A Source' button flashes.
Specifications and accessories: As RB-ADDA except Power: 10W maximum. Weight 1.7kg.