Side Chain/EXT Key Inputs
The electronically balanced Side Chain inputs are on stereo ¼ inch type A jack sockets, configured:
TIP = HOT, RING = COLD, SLEEVE = EARTH.
Inserting a mono jack plug will automatically unbalance the input.
1/4” Stereo Jack
HOT
COLD
GND
The sockets are internally normalled so that signal continuity is maintained when there is no jack plug inserted. If the unit is wired to a patchbay, then normalling must be carried out at the patchbay.
Balanced Circuits
Transformer or electronically balanced connections have the benefit of Common Mode Rejection which eliminates externally induced interference, such as mains hum etc. Balancing is especially useful when long cable runs are used between pieces of equipment.
Transformer balanced circuits have the added advantage of being fully floating, with the earth (ground) or screen being totally isolated from the signal. In installations where a difference in earth potential is likely to occur, this isolation prevents earthing problems which can, in some cases, damage the equipment.
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