JL Audio M200/2 Owner's Manual

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12  |  JL Audio - XD200/2 Owner’s Manual  
APPENDIX A:
Input Sensitivity Level Setting
Following the directions below will allow the 
installer to adjust the input sensitivity of the 
M200/2  simply and easily in just a few minutes 
using equipment which is commonly available in 
installation bays.
Necessary Equipment
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0 dB reference level in the frequency range  
to be amplified for that set of channels  
(50 Hz for subwoofer channels, 1 kHz for a 
midrange application). Do not use attenuated 
test tones (-10 dB, -20 dB, etc.).
The Nine-Step Procedure 
1)  Disconnect the speaker(s) from the  
amplifier’s speaker output connectors.
2)  Turn off all processing (bass/treble, loudness, 
EQ, etc.) on the source unit, processors (if 
used) and amplifier. Set fader control to center 
position and subwoofer level control to 3/4 of 
maximum (if used to feed the M200/2).
3)  Turn the “Input Sens.” control all the way 
down.
4)  Set the source unit volume to 3/4 of full 
volume. This will allow for reasonable gain 
overlap with moderate clipping at full volume.
5)  Using the chart on this page, determine the target 
voltage for input sensitivity adjustment according 
to the nominal impedance of the speaker system 
connected to the amplifier outputs.
6)  Verify that you have disconnected the speakers 
before proceeding. Play a track with an 
appropriate sine wave (within the frequency 
range to be amplified by the M200/2) at 3/4 
source unit volume.
7)
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connectors of the amplifier. If the channel  
pair is operating in stereo, it is only necessary  
to measure one channel. If bridged, make sure  
you test the voltage at the correct connectors  
(L+ and R–).
8)  Increase the “Input Sens.” control until the 
target voltage is observed with the voltmeter.
9)  Once you have adjusted the M200/2 to 
its maximum low-distortion output level, 
reconnect the speaker(s). The “Input Sens.” 
controls can now be adjusted downward if the 
amplifier requires attenuation to achieve the 
desired system balance. 
Do not increase any “Input Sens.” setting for 
any amplifier channel or channel pair in the 
system beyond the maximum level established 
during this procedure. Doing so will result in 
audible distortion and possible speaker damage.
It will be necessary to re-adjust the  
“Input Sens.” for the affected channels if any 
equalizer boost is activated after setting the  
“Input Sens.” with this procedure. This applies  
to any EQ boost circuit, including source unit 
tone controls or EQ circuits. EQ cuts will not 
require re-adjustment. 
Nom.
Impedance
Target AC Voltage
Stereo
Bridged
17.4 V
34.8 V
17.4 V
32.8 V
17.4 V
28.2 V
16.4 V
not recommended
14.1 V
not recommended