SoundCraft FX16II User Manual page 11

A 'Y' lead may be required to connect to equipment with separate send and
return jacks as shown below:
Stereo Returns 1 - 4
These accept 3-pole 6.35mm (1/4") jacks, or 2-pole mono jacks which will
automatically ground the 'cold' input. Use these inputs for sources such as
keyboards, drum machines, synths, tape machines or as returns from processing
units. The input is BALANCED for low noise and immunity from interference,
but you can use UNBALANCED sources by wiring up the jacks as shown, although
you should then keep cable lengths as short as possible to minimise interference
pick-up on the cable. Note that the ring must be grounded if the source is
unbalanced.
Mono sources can be fed to both paths by plugging into the Left jack only.
2-Track Return
These accept RCA phono plugs.
Mix Outputs
The MIX outputs are on XLR's, wired as shown, and incorporate impedance
balancing, allowing long cable runs to balanced amplifiers and other equipment.
Aux Outputs, Monitor Outputs & Channel Direct Outputs
These outputs are on 3-pole 6.35mm (1/4") jack sockets, wired as shown on
the left, and are balanced, allowing long cable runs to balanced amplifiers and
other equipment.
Headphones
The PHONES output is a 3-pole 6.35mm (1/4") jack, wired as a stereo output
as shown, ideally for headphones of 150Ω or greater. 8Ω headphones are
not recommended.
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