Mackie Big Knob Studio Command System Manual De Usuario

Oper

a

tion Guide

• 

If there is no sound in the PHONES

or 

STUDIO

outputs: 

• Make sure the PHONES/STUDIO OUTS 
SOURCE

button on the front panel is up 

(INPUT SOURCES selected). 
• Make sure the PHONES

or STUDIO

Level control is turned up.
• Make sure the STUDIO OUTS ON/OFF button 
is ON.

• 

If there is no sound in the MONITOR OUTPUTS

:

• Make sure the correct MONITOR SELECT 
button is pushed in and the trim control for the 
MONITOR OUTPUT is set correctly. 
• Make sure the cable connecting the MONITOR 
OUTPUT to the active speaker or power ampli-
fi er isn’t defective and the amplifi er/speaker 
combination is working correctly.

• 

Is the input connector plugged completely into 
the jack?

• 

Is it loud and distorted? Make sure the trim 
control and level switch for the selected input 
is set correctly. Reduce the signal level on the 
input source if possible.

• 

If possible, listen to the signal with headphones 
plugged into the input source device. If it sounds 
bad there, it’s not Big Knob causing the problem.

• 

Make sure the trim control for the MONITOR 
OUTPUT is set correctly and not overdriving the 
input stage of the active speaker or amplifi er to 
which it is connected.

• 

If a turntable is connected to the PHONO
inputs on Big Knob, make sure the ground wire 
from the turntable is connected to the GND
terminal on Big Knob.

• 

If a turntable is not connected to the PHONO 
inputs, make sure the PHONO INPUT SOURCE 
SELECT button is not pushed in. Also make 
sure the RCA shorting plugs are connected to 
the PHONO inputs when not being used.

• 

Check the signal cables between the input 
sources and Big Knob. Disconnect them one by 
one. When the noise goes away, you’ll know 
which input source is causing the problem.

• 

Sometimes it helps to plug all the audio equip-
ment into the same AC circuit so they share a 
common ground.

Details concerning Warranty Service are spelled out 
in the Warranty section on page 19.

If you think your Big Knob has a problem, please do 
everything you can to confi rm it before calling for 
service. Doing so might save you from the depriva-
tion of your Big Knob and the associated suffering.

These may sound obvious to you, but here are some 
things you can check. Read on.

• 

Our favorite question: Is it plugged in?

• 

Make sure the power cord is securely seated in 
the IEC socket

and plugged all the way into 

the AC outlet.

• 

Make sure the AC outlet is live (check with a 
tester or lamp).

• 

Is the POWER

switch on? Make sure the 

POWER switch on the rear panel is in the ON 
position (up).

• 

Is the POWER LED

on the front panel illumi-

nated? If not, make sure the AC outlet is live. If 
so, refer to “No Sound” below.

• 

Are all the lights out in your building? If so, 
contact your local power company to get power 
restored.

• 

If the POWER LED is not illuminated, and you 
are certain that the AC outlet is live, it will be 
necessary to have Big Knob serviced. There are no 
user serviceable parts inside. Refer to “Repair” at 
the end of this section to fi nd out how to proceed.

• 

Is the POWER LED

on the front panel illumi-

nated? If not, refer to “No Power” above.

• 

Is the correct INPUT SOURCE SELECT button 
selected? Make sure the LED above the INPUT 
SOURCE SELECT button is lit.

• 

Is the signal source turned up? Make sure the 
signal level from the selected input source is 
high enough to light up some of the INPUT 
meter LEDs on Big Knob’s front panel.

• 

Make sure the trim control and level switch for 
the selected input are set correctly.