Yamaha EMX3500 Operation Manual - Operating Tips

11

OPERATING TIPS

Cautions for Connected Sources

Please observe the following cautions when connecting

sound sources to the EMX3500:

• 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 EMX3500 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 electronic

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 at 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: turn

the PAD switch on, 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 loudest 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, turn the PAD switch off, 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 appropri-

ate 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

3 dB below the clipping level, it is okay if it flashes 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 positions

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.

Setting Channel and Master Faders

The final positions of the channel faders will naturally

depend on the overall mix you set up. However, there are

two important points you should keep in mind when setting

channel levels.

The channel faders have an optimum range that provides

the maximum control margin with minimum noise and

distortion. The optimum range for the channel faders on

the EMX3500 is between about “5” and “15” on their

scales. There is no rule that says you must avoid higher or

lower settings, but remember that the best sound quality

can be achieved within this range. Settings in this range

also provide sufficient leeway for later adjustments.

Remember, too, that changing the setting of any single

input channel fader will affect the overall output level. This

is why it is important to watch the VU meters when setting

the input channel and master stereo faders. These meters