5. OPERATION AND USAGE MANUAL
5.1. Start-up
To switch the mixer on push the switch labelled POWER (34) located in the rear panel. After a short time, the
POWER LED below the VU-Meters will light up. Although the switching noise produced by the NUO2 is very low
and almost inexistent when starting up the NUO2 with the main faders down, we highly recommend the "safe
power-up sequence", which means that you should switch on your audio devices in the following order:
1. Sound sources.
2. Mixer, equalizers, active filters.
3. Finally, power amplifiers.
Powering off should be done by following the exact reverse sequence in order to avoid any possible damage to the
loudspeakers.
5.2. Control Description
5.2.1. Input selector
Each channel features an input toggle switch selector (1).
5.2.2. Channel GAIN
All the NUO2 input channels have an easily accessible input sensitivity GAIN control (2). The GAIN controls adjust
the input level of each channel in order to compensate the different sources connected to the mixer. All input
sensitivity adjustments must be done very carefully using the VU-METER, and/or headphones as a reference. The
standard level reference used to mix audio signals is 0dBV. To optimize your mix, adjust your input the closest to
0dBV on the PFL VU-meter and never reach the "clipping" level using the red "warning" PEAK led as a reference
for each channel.
5.2.3. Equalization
The rotary tone controls for each channel provide a +10/-30dB boost/cut range for the bass (5) and treble (3)
bands, and +10/-25dB at the mid range (4). This great attenuation range is specially designed for creative live
performance. Also, any of the three frequency bands can be "killed on the fly" activating the ISOLATOR switches
(6-7-8) located below the BASS rotary knob on channels 1 & 2.
ATTENTION: Use equalization carefully, by boosting too much the low frequency range, you can induce an
excessive displacement of the speakers membrane.
5.2.4. Monitoring System
The NUO2 is equipped with a flexible and easy monitoring system that will allow the performers to finely tune PFL
(Pre-fader listening) and Mix levels of each input through the VU-METER and the HEADPHONES.
Each channel can be monitorized visually and pre-listened pressing the dedicated yellow PFL (9) led button.
For HEADPHONES monitoring, the PFL/MIX rotary potentiometer (14) allows you to blend a selected PFL together
with the main MIX Program. The VOL rotary potentiometer (19) controls the level of headphones output.
The NUO2 can display (15) at the same time PFL R+L signal (on the first left VU-METER bar) together with the
Main MIX Right and Left signals (second and third VU-METER bars).
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