Wiring Up - SoundCraft EFX User Manual

12

WIRING UP

Mic Input
The MIC input accepts XLR-type connectors and is designed to suit a wide
range of BALANCED or UNBALANCED low-level signals, whether from
delicate vocals requiring the best low-noise performance, or drum kits
needing maximum headroom. Professional dynamic, condenser or rib-
bon mics are best because these will be LOW IMPEDANCE. While you can
use low-cost HIGH IMPEDANCE mics, you do not get the same degree of
immunity to interference on the microphone cable and as a result the level
of background noise may be higher. If you turn the PHANTOM POWER on,
the socket provides a suitable powering voltage for professional condenser
mics.
DO NOT use UNBALANCED sources with the phantom power
switched on. The voltage on pins 2 & 3 of the XLR connector may
cause serious damage. BALANCED dynamic mics may normally be
used with phantom power switched on (contact your microphone
The input level is set using the input GAIN knob.
The LINE input offers the same gain range as the MIC input, but at a higher
input impedance, and is 20dB less sensitive. This is suitable for most line
level sources.
Start with the input GAIN knob turned fully anticlockwise when
plugging high level sources into the LINE input to avoid overloading
the input channel or giving you a very loud surprise!
Line Input
Accepts 3-pole 'A' gauge jacks, or 2-pole mono jacks which will automati-
cally ground the 'cold' input. Use this input for sources other than mics,
such as keyboards, drum machines, synths, tape machines or DI boxes.
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. Set the input level using the GAIN
knob, starting with the knob turned fully anticlockwise. Unplug any MIC
connection when using the LINE input.
Insert Point
The unbalanced, pre-EQ insert point is a break in the channel signal path,
allowing limiters, compressors, special EQ or other signal processing units
to be added in the signal path. The Insert is a 3-pole 'A' gauge jack socket
which is normally bypassed. When a jack is inserted, the signal path is
broken, just before the EQ section.
The signal from the channel appears on the TIP of the plug and is returned
on the RING, with the sleeve as a common ground.
The Send may be tapped off as an alternative pre-fade, pre-EQ direct out-
put if required, using a lead with tip and ring shorted together so that the
signal path is not interrupted.
manufacturer for guidance)
WARNING !
Soundcraft EFX/EPM User Guide Issue 1210