RADIAL ENGINEERING SW8-USB Automatic Switcher and USB Audio Interface

Automatic Switcher and USB Audio Interface

The RADIAL ENGINEERING SW8-USB is an automatic switcher and USB audio interface optimized for playback systems with on-stage redundancy, featuring dual USB inputs for direct connection to main and backup computers, and 8 high-quality audio channels to ensure maximum reliability in playing prerecorded music for live shows.
The RADIAL ENGINEERING SW8-USB is the ideal solution for performances or shows using backing tracks with redundant playback systems. This device combines two high-performance USB audio interfaces with an automatic switching function that detects interruptions and instantly selects the backup computer. Dual USB inputs with separate 24-bit/192 kHz converters allow two computers to be connected in tandem, so DAWs on both machines can connect to the RADIAL SW8-USB's audio and MIDI interface. Start/Stop synchronization between both computers can also occur via MTC (MIDI Time Code), ensuring seamless transition between playback platforms.

Specifications

• Switching between two redundant playback systems
• Two USB inputs with audio interface functions
• Automatic manual or continuous switching
• Line or mic outputs
• Synchronizes both playback systems via MTC
• The integrated solution for playing backing tracks
• PSU A/B: Dual green LEDs indicate that the SW8-USB is receiving power from each power supply. Only one connection is needed to power SW8-USB; the other is provided for redundancy to cover any power failures.
• Mic/Line: Selects Mic or Line impedance from the XLR outputs on the front panel. When set to Mic (outer position), the XLR outputs are also transformer-isolated to reduce noise from ground loops.
• Auto: Determines the SW8-USB switching mode: manual, user-controlled, or automatic, where the SW8-USB automatically selects B inputs if a fault is detected.
• Playback Activity: Dual green LEDs illuminate to indicate that the SW8-USB is receiving MTC (MIDI Time Code) or audio signals via SPDIF, depending on the Auto-Switch Input selector setting on the unit's rear panel.
• Mute: Mutes the analog outputs of the SW8-USB. While muting the XLR outputs, the audio signal still passes through the DB25 and TRS outputs on the rear panel.
• Standby: This switch keeps the SW8-USB's "A" input in automatic switching mode, regardless of whether MTC code or an audio signal on the SPDIF is being received. This function can also be activated remotely using the optional JR-2 footswitch.
• Input Select: Allows selection of active USB inputs. This switch is disabled when the SW8-USB is in Auto-Switch mode.
• Reset: Activating this switch after an error is detected allows the SW8-USB to return to inputs A.
• Alarm: The red LED illuminates and flashes when an error is detected on playback computer A, indicating that the SW8-USB has switched to playback on computer B.
• XLR Outputs: Analog outputs operate with Mic or Line impedance depending on the MIC/LINE switch setting.
• Ground Lift: Lifts pin-1 on the XLR output to help eliminate noise and hum generated by ground loops.
• PSU A & B Inputs: Connections for the 4-pin power supply block (included). The SW8-USB uses switching power supplies for easy international use.
• MIDI In/Out: Allows MIDI messages to pass to and from the computer on the active USB connection. When SYNC LOCK is deactivated, the signal sent to MIDI IN simultaneously feeds both the primary and backup computers, allowing an external MIDI controller to simultaneously trigger playback on both computers.
• Sync Lock: When activated, this switch sends MIDI information from USB-A to USB-B to enable synchronized playback between the two computers. Deactivating it allows simultaneous playback on both computers using an external MIDI controller.
• USB A & B: Type B USB connections for directly connecting primary and backup playback computers, on up to eight channels of analog audio playback. Compatible only with Mac OS, with 192kHz/24bit converters.
• Auto-Switch Input: Selects whether the signal from SPDIF or MTC is used by the SW8-USB's sensor inputs. The signal (SPDIF) should be used for the lowest latency when switching to inputs B.
• Start/Stop: The TRS connection allows sending MMC Start/Stop controls to the playback computers. A standard contact closure footswitch like the JR-1 can also be used for this function.
• DB25 Outputs: These outputs are always active regardless of the MUTE switch setting on the front panel, and follow the main or backup computer along with the main XLR outputs.
• 1/4" TRS Outputs: Balanced output jacks are wired in parallel with the DB25 monitor outputs. These outputs have Line impedance and are always active regardless of the MUTE switch setting on the front panel.
• JR-2 Footswitch Inputs: XLR and 1/4” TRS connections allow the optional JR-2 remote footswitch to control the SW8-USB's switching and standby functions. Standard 1/4” TS contact closure pedals and MIDI controllers can also be used to select the primary and backup computers.
• Alarm: This 1/4” TS connection can be used to trigger an external warning signal when a dropout is detected. This output can also be used to connect multiple SW8-USB units together for a higher number of channels.