JBL Ms 8 Service Manual

							
CTiONsEnglish
AUDIO OUTPUTS
Configurations
 
You can configure the MS-8’s eight outputs in a variety of ways, depending on the speakers that are 
installed in your vehicle. You can configure the MS-8 for a system with one-way (full-range), two-way or 
three-way front speakers, a one-way or two-way center speaker, side speakers, rear speakers and one 
or two subwoofers. Remember, however, that the total number of available channels is eight, so any 
combination of front, center, side, rear and subwoofer channels cannot total more than eight. For example, 
if you are allocating six channels for a pair of tri-amped, three-way front speakers, there will be only two 
remaining channels, which will not accommodate a pair of rear speakers and a subwoofer.
If your system will include more than eight channels, use additional separate amplifiers (connected to the 
MS-8’s line outputs) for the additional channels. For example, if you want to build a 7.1-channel system 
that includes bi-amped or tri-amped front speakers, use the MS-8 to generate the 7.1-channel outputs 
(seven full-range and one subwoofer). Connect the MS-8’s front line outputs to the inputs of an additional 
crossover (or amplifier containing an additional crossover) that will provide the separate channels required 
to drive the front midbass, midrange and/or tweeters separately. 
Use the Configuration Chart below to record which of your system’s speakers you have connected 
to which of the MS-8’s outputs. Keeping this record will simplify channel assignment during the setup 
procedure. See Main Menu, on page 35.
Output # Channel / Speaker Connected Output Connector Used
1         RCA          SPEAKER
2         RCA          SPEAKER
3         RCA          SPEAKER
4         RCA          SPEAKER
5         RCA          SPEAKER
6         RCA          SPEAKER
7         RCA          SPEAKER
8         RCA          SPEAKER
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CONNECTIONS
 
 MS-8                       
 
    
10  
						

							
CONNe CT i ON s
To ensure proper polarity, connect each MS-8 positive (+) terminal to the respective 
“+” terminal on the speaker. Connect the negative (–) terminals in a similar way.
+
–+ +
+
– –
–
+ +
+
– –
–
+–
Left front
(tweeter) Right front
(tweeter)
Left front
(midrange) Right front
(midrange)
Left side (coaxial) Right side
(coaxial)
Left rear (coaxial) Right rear
(coaxial)
MS-8
main unit Speaker-output
wiring harness
Vehicle
Speaker System
Speaker Outputs
If you’ll use the MS-8’s built-in power amplifiers to drive your system’s speakers, connect the speakers to the 
MS-8’s speaker outputs. Insert the included speaker-output wiring harness into the MS-8’s speaker output 
until it locks into place. See  Main Menu, on page 35.
IMPORTANT:  The MS-8’s speaker-output wiring harness’s wires have clear insulation. Each channel has a 
copper (positive or “+”) conductor and a silver (negative or “–”) conductor. We have labeled each conductor 
with its channel number and polarity, and pre-stripped it for easy connection to your system’s speakers. 
Make sure that the ( + ) and ( – ) wires do not touch each other. Touching wires can cause a short 
circuit that can damage the MS-8.
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CONNECTIONS
 
 MS-8                       
 
    
11  
						

							
e CT i ON s
NOTE: You can power some of the system's speakers by the MS-8's amplifiers and some by outboard 
amplifiers, but you should use only one connection type per output. For example, output channel 1 may use the 
MS-8's amplifer OR an outboard amplifier, but not both. Be sure to use the chart above to note which speakers 
are connected to which MS-8 channels.
+ –
++
– –
+
+
+
–
–
–
+ –
Left front
(Tweeter)
Left front
(midrange)
Left rear(coaxial)
Not
used
Speaker output wiring harness
Subwooferamplifier
Line output
#6
Not
used Right rear
(coaxial)
Subwoofer Right front
(midrange) Right front
(Tweeter)
Vehicle
Speaker  System
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CONNECTIONS
 
 MS-8                       
 
    
12  
						

							
+ –
++
– –
+
+
+
–
–
–
+
–
Left front
(tweeter)
Left front
(midrange) Left rear
(coaxial)
Front
speaker
amplifier Rear
speaker
amplifier Subwoofer
amplifier
RCA
audio cables
MS-8 main unit
Ch. 8 is unused
in this example
Right rear(coaxial)
Subwoofer Right front
(midrange)
Right front
(tweeter)
Vehicle
Speaker  System
CONN e CT i ON s
Line Outputs
If you’ll be using additional outboard power amplifiers to drive your system’s speakers, connect their inputs to 
the MS-8’s line-output connectors. You can power some of the system’s speakers by the MS-8’s amplifiers 
and some by outboard amplifiers, but you should use only one connection type per output. For example, 
Output Channel 1 may use the MS-8’s amplifier OR an outboard amplifier, but not both. Be sure to use the 
chart above to note which speakers you have connected to which of the MS-8’s channels.
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CONNECTIONS
 
 MS-8                       
 
    
13  
						

							
DISPLAY
Use the included 6m (19.7 ft) cable to connect the display unit to the MS-8’s main unit’s display connection. 
Insert the cable’s straight connector into the main unit and the right-angle connector into the display. 
NOTE: The display unit must be connected during setup but may be disconnected after setup and after 
you’ve made any additional adjustments in the Audio Controls menu (see Audio Controls Menu, on page 36). 
If the display unit is disconnected after setup and final adjustment, you will not be able to make any additional 
MS-8 adjustments, and the remote control will not function. See  Main Menu, on page 35.
MICROPHONE
The included binaural microphone headset must be connected to the MS-8’s Mic connection during the 
calibration/setup process. Once setup is complete, unplug the microphone headset and store it in a safe 
place. 
IMPORTANT: Do not use any other microphone with the MS-8.
REMOVE FOR
SOFTWARE UPDATE
Plug angled connector into display Plug straight connector
into main unit
Connect to mic input
CONN e CT i ONs
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CONNECTIONS
 
 MS-8                       
 
    
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CONNe CT i ON s
After downloading a firmware upgrade into your PC, remove the sticker and connect the 
Update port to a USB port on your PC. Follow the directions that accompany the upgraded 
firmware to upload the new firmware from your PC to the MS-8.
REMOVE
FOR
SOFT WARE
UPD ATE
UPDATE
Use the Update port only for firmware upgrades. We have covered it with a sticker that you should leave in 
place until you are ready to install a firmware upgrade that you will download from www.JBL.com.
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CONNECTIONS
 
 MS-8                       
 
 
RESETTING THE MICROPROCESSOR 
 
If the MS-8 stops responding to the remote control (even after you’ve replaced the 
remote’s battery) or fails to operate in the way this manual describes, use a pen or 
similar pointed object to press the Reset button on the main unit  
NOTE: Pressing this Reset button will NOT erase the calibration settings. 
 
To erase all settings and set the unit back to factory defaults, this should be done in 
the system menu; see page 39 of the owner’s manual for details 
 
 
 
    
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Usi NG   T he  re MOT e  CONT r
OL
Volume Up and Down buttons:  Pressing either of these buttons at any time (except during the 
setup/calibration process) will display the MS-8’s  System Volume screen, allowing you to change 
the audio volume. The volume range is between –80dB and 0dB.
Navigation and select buttons:  Use the four navigation buttons (Up, Down, Left and Right) to navigate 
through the MS-8’s various setup and operation screens. The Select button selects or otherwise 
changes the state of a highlighted item.
Back/menu button:  Momentarily pressing this button causes the display to revert to the next-higher 
menu. Holding the button reverts to your default screen (either the Main Menu or Audio Controls screen) 
from whatever screen is active at the time. See Default Screen, on page 40.
Mute button:  Press to mute the sound; press again to restore the sound. (Pressing either the Volume 
Up or Volume Down button also restores the sound.)
Volume Down button Volume Up 
button
Select
button
Left/Right
navigation
buttons
Mute 
button
Up/Down
navigation buttons
Back
button
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USING THE REMOTE CONTROL
 
 MS-8                       
 
    
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Tr OUBL esh OOT i NG
If your MS-8 doesn’t seem to be working the way it should, read this section to 
see if the problem and possible solution are listed here. If, after you try all of the 
solutions listed here, the problem persists, contact JBL Customer Service at 
516.255.4JBL (4525).
POWer
s
OUN d
The power LED does not 
illuminate.
Symptom
Symptom Possible Cause
Possible Cause Solution
Solution
The power LED illuminates, 
but the display does not 
illuminate.
There is no sound in all 
channels. Improper input connections.
Calibration/setup procedure 
has not been performed.
Incorrect input is selected
on the MS-8
The MS-8’s System Volume 
is turned all the way down. Set the MS-8 System 
Volume at –20dB. See 
Acoustic Calibration
, on 
page 32, and Volume Up 
and Volume Down Buttons , 
on page 35.
Select the correct input 
using the MS-8’s Input 
Selection menu. See Input 
Selection Menu
, on page 35.
Perform the calibration/
setup procedure. (The 
procedure must be 
performed before the MS-8 
will pass an audio signal 
through to its outputs.) See 
Calibration/Setup
, on page 
24. Confirm that all the required 
channels of the source unit 
are properly connected. See 
Audio Inputs
, on page 7.
The +12V, Gnd or Rem In 
terminals are not properly 
connected.
The fuse is blown.
The display is not properly 
connected.
The MS-8’s microprocessor 
needs to be reset. Replace the fuse with an 
identical 25A fuse.
Check the connections at 
display and at main unit. 
See Connections: Display , 
on page 14.
Press Reset button with a 
pen or similar object. See 
Resetting the 
Microprocessor , on page 41.
Confirm that all power 
connections are correctly 
made according to this 
manual. See Connections: 
Power
, on page 5.
The head-unit or source-unit 
volume control is turned all the 
way down. Turn the head-unit or 
source unit volume up to a 
normal level. 
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TROUBLESHOOTING
 
 MS-8                       
  NOTE PAGE NUMBER REFERENCES IN THIS SECTION REFER TO THE OWNERS MANUAL   
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Tr OUBL esh OOT i NG
sOUN d
Symptom
Possible Cause Solution
There is no sound in one or 
more channels.
The sound comes from the 
incorrect speaker.
Sound comes from only the 
left or right side speakers; or 
sound comes from only the 
front or rear speakers. The Balance and/or Fader 
controls are set all one way 
or another.
Use the MS-8’s System 
Levels screen to set the 
controls to their center 
positions. See Audio 
Controls Menu
, on page 35.
Incorrect output connection.
Incorrect channel assignment.
Perform the Input 
Setup (page 25) and 
Output Setup (page 26) 
procedures again. (See 
the If you make a mistake 
sidebar, on page 27.) 
Before beginning the 
procedures, make sure 
to confirm and document 
which speakers are 
connected to which MS-8 
Confirm that the speaker is 
connected to the correct 
MS-8 speaker output or 
to the correct outboard- 
amplifier channel.
Improper input connection.
Improper output connection.
Improper speaker connection to 
outboard amplifier. Outboard amplifier channel is 
not functioning. Troubleshoot the outboard 
amplifier and replace it, if 
necessary.
Confirm that the speaker is 
properly connected to the 
outboard amplifier. Confirm that the speaker 
in question is properly 
connected to the MS-8’s 
speaker output. See Audio 
Outputs
, on page 10.
If the speaker is connected 
to an outboard amplifier, 
confirm that the outboard- 
amplifier channel is properly 
connected to the MS-8. See 
Audio Outputs , on page 10.
Confirm that all required 
channels of the source unit 
are properly connected. See 
Audio Inputs
, on page 7.
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TROUBLESHOOTING
 
 MS-8                       
 
    
18  
						

							
sOUN d
The Aux input level is not 
properly set.
The source player’s volume 
control is set too low. Set the source player’s 
volume control to a higher 
level.
The source connected to the 
Aux input is too quiet or too 
loud.
The sound in all speakers is 
distorted. The MS-8’s System Volume 
control and the head unit’s 
volume control are not properly 
adjusted.
The MS-8’s Bass Control and/
or Graphic EQ bass bands 
are set with too much boost, 
combined with a high System 
Volume setting. Reduce the Bass Control 
and/or Graphic EQ boost 
levels. We recommend 
never combining high levels 
of Graphic EQ bass-band 
boost with high Bass 
Control boost.
If you have connected the 
front speakers to be driven 
directly by the MS-8’s 
internal amplifier, set the 
MS-8’s System Volume at 
–20dB. 
If you have connected 
the front speakers to an 
external, higher-powered 
amplifier that is connected 
to the MS-8’s line outputs, 
set the MS-8’s System 
Volume to a level lower than 
–20dB.
In either case, you should 
use the head unit’s volume 
control to control the 
system’s volume. You may 
need to make a minor 
adjustment to the MS-8’s 
System Volume setting to 
allow you to use more of 
the range in the head unit's 
volume control.
If you hear distortion when 
the head unit’s volume 
control is at higher settings, 
increase the MS-8’s System 
Volume to compensate. 
This change will let you 
keep the head unit’s volume 
control within a lower (more 
distortion-free) portion of its 
range. Use the MS-8’s System 
Levels screen to set the 
Aux level so that the Aux 
source’s level matches 
the level of the head unit 
source. See Audio Controls 
Menu
, on page 35.
Tr OUBL esh OOT i NG
Symptom
Possible Cause Solution
44
TROUBLESHOOTING
 
 MS-8                       
 
    
19