True to the Music
Radial Engineering Ltd.
SW8 Owner’s Manual
Audio Outputs
The SW8 offers two audio outputs; the line-level DB25 output connector and the front panel mic-level XLR jacks. Which output you
choose to use will depend on where the SW8 is set up. For instance, the DB25 output will typically be used at the FOH mix position to
feed line-level signals to the console while the XLR outputs would feed mic-level signals to the on-stage mic snake. The DB25 direct
thru-put and the mic-level XLR outputs can be used at the same time should you want to connect two mixing consoles using different
signal formats. For example, the DB25 output may be connected to the on-stage monitor console while the XLR outputs are connected
to the FOH console through the mic snake.
DB25 Output
The rear panel DB25 connector is a direct thru-put connection providing a duplicate of the input signal. The signal path from the
inputs to the DB25 direct thru-put is 100% passive with no active electronics to color the sound. The audio signals only cross the
gold contacts of the sealed relays before reaching the DB25 output connector. Use the rear panel DB25 connector when the SW8 is
connected to the line-level console inputs.
XLR Outputs
The front panel XLR jacks produce a balanced, mic-level signal and are transformer isolated to eliminate buzz and hum caused by
ground loops. The mic-level outputs allow the SW8 to interface with mic splitter snakes and console mic-preamps.
If you hear distortion from the XLR outputs it is likely that the multi-track output level is overloading the transformers. The GLOBAL
PAD switches in a -20dB PAD on all eight channels to protect against overloading the transformer.
Each channel features a ground LIFT switch that disconnects the pin-1 signal ground at the XLR outputs. It may be used on a per-
channel basis to accommodate specifi c grounding needs. Typically this will be set to lift the ground (pushed in) so the transformer can
decouple the signal grounds.
Internal Ribbon Connector
An internal ribbon connector allows the SW8 to route the eight transformer isolated mic-level outputs to the rear panel DB25 connector.
This allows mic-level connections to be made on the rear panel instead of the front XLR jacks. This modifi cation will disconnect the
front XLR jacks and the SW8 will only be able to output mic-level signals (no direct thru-put is available in this mode). Note that after
this modifi cation the front panel LIFT switches will continue to function as normal.
To access the internal ribbon connector remove the top panel. Locate the ribbon cable for the DB25 Direct output. Gently remove the
ribbon connector from the circuit board and plug it into CONN4 marked “XLR OUT” on the circuit board. The red stripe on the ribbon
cable should be on the same side as the rear panel and the notch on the connector should match with the notch silk screened on the
circuit board.
4
Direct out
ribbon cable.
CONN4
XLR OUT
Notch
