Operating Tips - Inter-m PX-1650 Operating Manual

Operating Tips

Operating Tips
※ CAUTIONS FOR CONNECTED SOURCES
Please observe the following cautions when connecting sound sources to the PX-1650.
- TURN THE POWER OFF FIRST
Always make sure that the mixer's POWER switch is turned off before connecting or disconnecting any
cables. Failure to do so can damage the PX-1650 or connected equipment.
- TURN THE MIXER ON LAST
Always turn the mixer's POWER switch on after first turning on connected sound sources such as electron-
ic instruments or audio equipment.
- DO NOT CONNECT AMPLIFIED INPUT
Never connect the speaker-level output of any amplifier to the mixer's inputs unless you use a suitable
high-level attenuation pad or "direct box" to lower the signal's level.
※ MATCHING INPUT LEVELS
When matching input levels, it is a good idea to first make sure that the speaker systems are disconnected
from the mixer's speaker outputs (This must be done with the mixer's POWER switch turned off.). The sound
can be monitored using a pair of headphones plugged into the front-panel PHONES jack-but make sure
that the master stereo faders are set to their minimum levels as first, then raise them just enough to produce
a comfortable sound level when you actually begin monitoring input signals and matching levels.
Once all your sources are connected and the entire system is turned on, it is important to accurately match
the input sensitivity of each input channel with the source signal it will receive. Do this one channel at a
time. Begin by setting the lowest possible sensitivity for the input. Set the GAIN control to -16, and slide the
channel fader to between "10" and "5" on its scale.
Now apply a signal to the input. Play the connected source instrument at the loudest level it will produce in
actual use-or if the source is a microphone, have the vocalist sing his or her loudest note into it-and watch
the channel's PEAK indicator carefully. If it lights at this point, the output level of the source must be reduced.
Normally, however, you will have to increase the input sensitivity to achieve optimum matching.
Gradually increase the setting of the GAIN control until the PEAK indicator just barely flashes on the loud-
est peaks. If you turn the GAIN control up all the way and the PEAK indicator still does not light, then
reduce the GAIN control setting to minimum, and gradually increase the GAIN setting again. This time the
PEAK indicator should light somewhere in the GAIN control range. If it does not, check that the source is
functioning properly and that it is properly connected to the appropriate input of the mixer. You may also
want to check the connecting cable for faults.
Since the PEAK indicator lights when the channel signal is 3dB below the clipping level, it is okay if it flash-
es briefly on loud peaks. In fact, this is about the optimum input sensitivity setting. When you've matched
the first channel, set its fader to minimum and begin matching the next channel. Repeat this procedure for
each channel you will use in the mix.
Once the input level of each channel has been matched, set the master stereo faders to their minimum posi-
tions and turn the POWER switch off. Reconnect the speaker systems, then turn the power back on. The
master faders can now be gradually raised to their operating levels.
STEREO BUILT IN X-OVER
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PX-1650