BASS BOOST CONTROLS
Tuning Hint: A trunk mounted sub whose output has to “fight” through a rear deck or a back seat often benefits from the 12 dB/octave slope which lets more upper bass content pass through. A sub that fires directly into the listening environment is more likely to benefit from a 24 dB/octave slope.
Note: The above hint is not
Protect |
Bass Boost Controls
Bass Boost
Remote
Bass Port
The preamp output signal is not affected by the “Bass Boost” processing selected for the amplifier or by any crossover filter selected (if the input signal is
The signal level of the “Preamp Output” is
Speaker loads below 2 ohms nominal are not recommended and may cause the amplifier to initiate a protection mode which reduces power output.
You will notice that there are two “+” positive connections and two
appropriate filter slope.
3) Precise Frequency Selection: The filter |
frequency markings on the front panel of |
the amplifier are for reference purposes and |
are generally accurate to within 1/3 octave |
or better. If you would like to select the filter |
frequency with a higher level of precision, |
consult Appendix B (page 13) of this manual. |
This chart gives you a more accurate frequency |
for each of the forty detented positions of the |
frequency selection control. This method can |
be very useful if the amplifier is mounted in |
a location where you can’t see the front panel |
markings easily. |
4) Defeating the Amplifier Filter: The Low- |
Pass filter can also be defeated completely, |
by switching the “Mode/Slope” switch to |
the “Off” position. This is useful if you are |
using an external active crossover in the |
system. Keep in mind that turning the internal |
crossover off also defeats the “Bass Boost” |
processing (see next section for details). With |
the internal crossover turned off, the A1400’s |
1)“Bass Boost”: This switch allows the user to activate a 6 dB boost centered at 48 Hz. The “Filter Mode” switch in the “Amplifier Controls” section must be in the “LP” position for the bass boost to be functional.
2)“Remote Bass Port”: This port allows you to connect an optional remote boost knob (sold separately, JL Audio Model
0 - 12 dB of boost to be selected.
PRE-OUTS
The A1400 incorporates a
If you plan to use the
SPEAKER OUTPUTS
The A1400’s speaker outputs are designed to accept 16 AWG - 8 AWG wire.
The A1400 is designed to deliver power into speaker loads equal to or greater than 2 ohms.
To connect the speaker wires to the amplifier, first back out the set screws own the top of the terminal block, using the supplied 2.5 mm hex wrench. Strip 1/2 inch (12 mm) of insulation from the end of each wire and insert the bare wire into the terminal block, seating it firmly so that no bare wire is exposed. While holding the wire in place, tighten the set screw firmly, taking care not to strip the head of the screw.
parallel speaker connection. If only connecting one pair of speaker wires, it is not necessary to use both sets of connections.
upper frequency response limit is 250 Hz, due |
to its |
CH 1 (Left)
CH 2 (Right)
Power |
8 | JL AUDIO A1400 | JL AUDIO A1400 | 9 |