SoundCraft Audio Mixing Console Model Spirit Studio User Manual

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and other equipment which would otherwise show up

as hum. If the output is driving a device or amplifier

that has an unbalanced input, connect the -ve(cold) sig-

nal to the ground at the destination, not at the output of

your SPIRIT STUDIO console.

Polarity

You will probably be familiar with the concept of polar-

ity in electrical signals and this is of particular

importance to balanced audio signals. Just as a bal-

anced signal is highly effective at cancelling out

unwanted interference, so two microphones picking up

the same signal can cancel out, or cause serious deg-

radation of the signal if one of the cables has the +ve

and -ve wires reversed. This phase reversal can be a

real problem when microphones are close together and

you should therefore take care always to connect pins

correctly when wiring audio cables.

Source

Input

GND
LINK

BALANCED TO BALANCED

UNBALANCED TO BALANCED

UNBALANCED TO UNBALANCED

If ground link absent, or mains earth isolated from

source ground, then connect shield at both ends

Grounding and

Shielding

For optimum performance it is vital that all signals are

referenced to a solid, noise-free earthing point and that

all signal cables have their screens connected to

ground. To avoid earth loops, use balanced connec-

tions where possible and ensure that all cable screens

and other signal earths are connected to ground only at

their source and not at both ends.

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