30. +4 / -10 Switch
This button, located on both stereo
input channels, is used adjust the
input sensitivity of the corresponding
channels, which will adapt the mixer
to external devices which may use
different operating levels. If the input
source is -10 dBV (consumer audio
level), it is best to engage the switch, allowing the
signal to be heard. The +4 dBu level is suitable for
Professional Audio signals, which are considerably
higher than the consumer level. However, if you are
unsure of the source's operating level, we suggest
leaving the switch disengaged until you test the
source's signal. You can then engage if necessary
(if the level of the input signal is obviously too low).
DIGITAL EFFECT SECTION
31. Digital Effect Display
This 2-digital numeric display shows the program
number that is currently applied to your EFX audio
signal. When you rotate the Program control, you
can scroll through different program numbers;
however the display will revert back to the original
program if a new program is not selected within a
few seconds. For a list of available effects, please
observe the Digital Effect Table.
32. Sig and Clip Indicators
Located within the Digital Effect Display are Clip and
Sig LEDs. The Sig LED will light up when any signal
is received by the effect processor, and the Clip
LED will light up shortly before excessive signals
are dynamically clipped. If the Clip LED lights up
too often, it may be advisable to turn down the AUX
2/EFX control on one or all input channels to ensure
the signal level is not excessive.
HELIX BOARD 12 FIREWIRE MKII
33. Program Control
This control is used to scroll through the various
effects. Turning the control clockwise will allow users
to ascend into higher program numbers, and turning
it counter-clockwise will allow users to descend into
lower program numbers. Pushing this control will
apply the new effect. When a tap-delay effect is
selected, pressing this control will allow users to
select the tap-delay time.
By pushing the button several times, the effect
processor interprets the time between last two
pushes and remembers this as the delay time – until
the button is pushed again. This is kept even after
the power is turned off. When the tap delay effect
is selected, a small LED will flash within the digital
effect display window at the selected intervals.
MASTER SECTION
34. AUX Stereo Return Controls
These controls adjust the signal level of audio fed
through to the AUX Stereo Return inputs, which will
be added to the MAIN L-R mix. The AUX Return
2 control also acts as the built-in DSP Effect level
control, when no device is plugged into the AUX 2
Return jacks.
35. EFX to Monitor button
This button allows users to select the destination
of the AUX Return 2 signal. Pushing it in sends the
signal to the AUX Send 1 mixing bus.
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