Yamaha MC2410M Operating Manual page 13

The following setting will generally apply:
Low output dynamic microphones: -50 dB.
Medium output condenser microphones:-40 dB.
Preamplified electric instruments and low level {creative
audio or hi-fi) line sources:-20 dB.
High level (professional) line sources: +4 dB
We suggest the following procedure for setting input
levels:
1. Connect all input sources to their respective channels.
Monitor the mix on low-impedance type headphones.
DO NOT connect the console to any power amplifiers
yet.
2. Set the phones LEVEL control to 'V'. You will monitor
each input channel by pressing the CUE button on the
respective input channel module.
3. Set master fader #1 to about "0"-this is the position that
gives rated output level, which can be checked on the
corresponding VU meter.
4. Adjust input channel mix level control #1, on the channel
that you are setting, to position This will send the
input signal to master output #1, at rated output level.
5. Start with the lowest input sensitivity (PAD switch in the
DOWN position, GAIN at -16 dB). With the input CUE
button on, so that you can monitor the signal on head¬
phones, gradually increase sensitivity using the GAIN
control until the signal is clearly audible. If sensitivity is
too low even with the GAIN control at maximum, return
this control to the -16 dB position, set the PAD switch in
the UP position, and slowly, bring up the GAIN control
again.
At the optimum setting, VU meter #1 should be peaking
around 0 VU. If the meter consistently shoots past 0 VU,
or if the signal sounds distorted in your headphones, the
input sensitivity is too high, and you will need to
decrease it until the levels are correct.
As a visual aid, the peak LED on the VU meter should
only light on occasional loud peaks. If it is on longer than
this, the input sensitivity should be reduced.
6. Repeat this procedure for each input channel, until all
channels are set for proper input sensitivity. Turn the
mixing console power OFF, and connect your outputs.
Turn the power ON again.You are now ready to adjust
the remaining mix controls on each channel.
IMPORTANT: The console, and all signal processing
devices connected to it, MUST be turned on BEFORE the
power amplifiers are turned on. If this procedure is not
followed, the console turn-on transient could easily
cause damage to your loudspeakers. This procedure
should be reversed when the system is turned off.