Mackie LM-3204 Owner's Manual - Important Sensitivity

5

IMPORTANT SENSITIVITY

ADJUSTMENT PROCEDURE!

So important we put it first, before anything

else.

To fully achieve the LM-3204 Mixer’s

impressive headroom and specs, you should

always 

“tune” the input sensitivity for each

channel.

FOLLOW THIS PROCEDURE FOR EACH

CHANNEL IN USE

1.

Set the Control Room, Phones, Left and Right

Master Fader and Solo controls all the way

off

. (As you are working through the steps,

you can bring these controls up a bit to hear

what you are doing, but be careful. There’s a

lotta level in this mixer.)

2.

Apply signal to channel input.

Insert a stereo line input into the correspond-

ing Left and Right Input jacks at the rear of

the mixer.

or

Insert a mono line input into the correspond-

ing Left Input jack on the rear of the mixer.

3.

Set channel strip controls as follows:

Gain control at “U” detent.

Solo switch 

down

.

Mute switch 

up

.

Balance control at “U” detent.

EQ controls at “U” detent.

Aux controls fully counterclockwise 

(off)

.

4.

Apply an audio signal to the input. The

material and level you use to set up the mixer

should be vaguely representative of what you

will really be doing when you really do it. If

you’re connected to a tape deck or a CD

player, put some music on and push the

button! If you’re hooked up to a synthesizer,

tickle those plastic ivories!

5.

The channel’s –20dB LED should light. The

L/R main meters will show the actual

internal operating level of soloed signals.

Now you will optimize levels.

For a meter reading of 0dBu with +4dBu

input (line level) signals, the settings in step 3

should be just about right. Adjust the channel

Gain control slightly so that you get peaks that

regularly hit 0dB on the Left and Right meters.

For –10dBV signals, you may have to turn

the channel Gain control clockwise to

boost the signal to read 0d                      B on

the Left and Right meters.

On the other hand, you might have to deviate

from this approach on certain channels. For

example, you don’t want to set the hi-hat cymbal

channel at 0dB. Use your judgement on this.

The 

Long Arm Exercise

: For Microphone

signals (using an onboard Mackie mic

preamp), leave the channel Gain setting at

the “U” detent and instead adjust the Mic

Trim pot on the rear of the mixer until you

get peak levels of around 0dB on the Left and

Right meters. Remember, the sound coming

in the microphone should be typical of what

you will really be using. For patching instruc-

tions, see page 11, “Microphone

Preamplifiers.”

6.

If desired (optional):

Adjust the channel strip’s EQ to about what

you will be using during the session.

Repeat Step 5.

7.

Return the channel strip’s Solo button to the

up

 position.

8.

Repeat steps 1–7 on the next channel that is

being used.

9.

As you un-solo the channel strips to listen to

your mix, ease up the Left and Right master

faders to set a good mix level on the meters,

with occasional peaks of 0dB.