Radial Engineering SW8-USB

Radial SW8-USB is the ideal solution for professional on-stage backing tracks playback systems via redundant Mac-based systems. It features dual USB 2 (type A) interfaces for direct connection of both the main and backup computers; synchronization between the two is via MTC (MIDI Time Code). The system switches between the two computers immediately and without perceptible drop-outs, in case data transmission errors are detected, this ensures continuity and peace of mind of the performance.

Notable features:

• Switching between two redundant playback systems
• Two USB inputs with audio interface functions
• Automatic manual or continuous switching
• Line or micro outputs
• Synchronizes both playback systems via MTC

The integrated solution for playing backing tracks

SW8-USB is the ideal solution for Performances or Shows using backing tracks with redundant playback systems. In fact, this instrument combines two high-performance USB audio interfaces inside, integrated with an automatic switching function that detects any 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 used on both machines can connect to SW8-USB's audio and MIDI interface. Start/stop synchronization between both computers can also take place via MTC (MIDI Time Code), thus ensuring switching without appreciable drop-outs between playback platforms.

Front Panel

• 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 the SW8-USB, the other is provided for redundancy to make up for any power failures.
• Mic/Line - Selects the Micro or Line impedance from the XLR outputs on the front panel. When set to Mic (external 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, in which SW8-USB automatically selects the B inputs when a fault is detected.
• Playback Activity - Dual green LEDs light up to indicate that SW8-USB is receiving MTC (MIDI Time Code) or audio signals via SPDIF, depending on the setting of the Auto-Switch Input switch on the rear panel of the unit.
• Mute - Mutes the analog outputs of SW8-USB. Although it mutes the XLR outputs, the audio signal still passes through the DB25 and TRS outputs on the rear panel
• Standby - This switch keeps input A of SW8-USB on auto-switching mode, regardless of receiving or mending the MTC code or audio signal on the SPDIF. This function can also be activated remotely using the optional JR-2 footswitch
• Input Select - Selects the active USB inputs. This switch is disabled when SW8-USB is in Auto-Switch mode
• Reset - Activating this switch after an error is detected allows SW8-USB to return to inputs A.
• Alarm - The red LED lights up and flashes when an error is detected on playback computer A, displaying that SW8-USB has switched to playback on computer B
• XLR Outputs - Analog outputs operate with Micro or Line impedance depending on the MIC / LINE switch setting.
• Ground Lift - Raises pin-1 on XLR output to help eliminate noise and hum generated by Ground Loops

Rear Panel

• PSU A and B Inputs - Connections for 4-pin power supply block (supplied). SW8-USB uses switch-mode power supplies to allow easy use internationally.
• MIDI In/Out - Allows MIDI messages to be passed to and from the computer over the active USB connection. When SYNC LOCK is deactivated, the signal sent to the MIDI IN simultaneously feeds both the primary and backup computers, allowing an external MIDI controller to be used to trigger playback on both computers at the same time.
• Sync Lock - When activated, this switch sends MIDI information from USB-A to USB-B to enable synchronized playback between the two computers. Turning it off enables simultaneous playback on both computers using an external MIDI controller.
• USB A and B - USB type B connections to directly connect primary and backup playback computers, on up to eight channels of analog audio playback. Compatible with Mac OS only, with 192kHz / 24bit converters.
• Auto-Switch Input - Selects whether the signal from SPDIF or MTC is used by the sensor inputs of the SW8-USB. The signal (SPDIF) should be used for the lowest latency when switching to the B inputs.
• Start/Stop - The TRS connection allows Start/Stop MMC controls to be sent to playback computers. A Standard contact closure footswitch such as 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 connected 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 - The XLR and 1/4 TRS connections allow the JR-2 remote footswitch (optional) to control the switch and standby functions of the SW8-USB. standard 1/4 TS footswitches with contact closure, and MIDI controllers can also be used to select 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-USBs together for more channels.

Applications of SW8-USB

Connection to redundant playback computers

SW8-USB connects directly to primary and backup computers via USB, eliminating the need for additional, bulky and expensive audio interfaces. By connecting the balanced analog outputs to the PA system and activating the automatic switching mode, it is possible to switch instantly in the event of an error to the backup system without interrupting the playback of backing audio tracks. To manually switch inputs or place the SW8-USB in Standby between tracks, a JR-2 footswitch (optional) can be used.

Connect multiple SW8-USB devices for up to 24 playback channels

Up to three SW8-USB units can be connected at the same time, thus the system provides 24 redundant playback channels for even greater needs. You can connect each SW8-USB directly to the main and backup computers, and connect all three with TRS cables so that they can switch simultaneously.

Connect multiple SW8-USBs via a Thunderbolt Hub

Up to 3 SW8-USB units can be connected together for up to 24 tracks in playback. To achieve this with only one connection to each computer, connect all three SW8-USB units to a Thunderbolt Hub with the appropriate transfer rate for the three units to work simultaneously.