JL Audio HD750/1 Owner's Manual page 18

APPENDIXB:
Precise Frequency Selection Chart
"FILTER FREQ"
Detent Panel Actual
Number Marking Freq.
Full counter-clockwise: 58
01... . 53
02... .. "50". . . .53
03 53
04......... . .53
05 .54
06 56
07 58
08 "60". ..60
09 62
10 64
11 66
12 68
13.......... .. 71
14......... . 74
15.. . 76
16 . "80"... . 80
17.......... . 83
18........... .. ..87
19.......... . 91
20.. . 94
21 . 99
22 104
23 109
24 "120" 115
25. .. 121
26... .. 128
27 .. . 137
28... . 147
29 160
30.......... .. 174
31 .. 191
32 "200" 211
33......... .. 236
3 4 . . . . . . . . . . .. 269
35.. .. 309
36. . 369
37................ .. .443
38 "500" 484
39 525
Full-clockwise: 528
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JL Audio - HD750/1 Owner's Manual
APPENDIXC:
Input Sensitivity Level Setting
JL Audio amplifiers utilizing the Regulated
Intelligent Power Supply (R.I.P.S.) allow
delivery of their rated power when connected
to any load impedance from 1.5 - 40 per
channel and when connected to a charging
system with any voltage from 11 - 14.5V.
This design is beneficial for many reasons.
One of these reasons is ease of setup.
Because each JL Audio amplifier will
always deliver the same amount of power
within its operational range of impedances
and supply voltages, the maximum,
unclipped output is very predictable.
This makes setting the gain structure via the
input sensitivity controls very simple. Following
the directions below will allow the user to adjust
the input sensitivity of the amplifier(s) simply
and easily in just a few minutes using equipment
which is commonly available in installation bays.
Necessary Equipment
• Digital AC Voltmeter
• CD with a sine-wave test tone recorded at
o
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). The CleanSweep·
Calibration Disc contains the appropriate
test tones and is available for sale at
http://store.jlaudio.com Do not use attenuated
test tones (-10 dB, -20 dB, etc.).
Do not increase any "Input Sens." setting 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, source unit tone controls or EQ
circuits. EQ cuts will not require re-adjustment.