TURN-ON LEAD
The A1400 uses a conventional +12V remote
The A1400’s “Remote”
INPUT SECTION
The A1400’s input section allows you to send signal to the amplifier section through the use of two
CH 1 (Left)
Input Voltage
Low High
CH 2 (Right)
You may run a stereo or a mono signal into the inputs of the amplifier. The amplifier’s input section automatically sums stereo signals to mono for the internal amplifier section. The amplifier will operate with only one input connection (left or right), but will require an increase in input sensitivity to overcome the loss of signal. If a mono input signal is to be run, we recommend that you use a
INPUT VOLTAGE RANGE:
A wide range of signal input voltages can be accommodated by the A1400’s input section (200mV – 8V). This wide range is split up into two
The “Low” position on the “Input Voltage” switch selects an input sensitivity range between 200mV and 2V. This means that the “Input Sens.” rotary control will operate within that voltage window. If you are using an aftermarket source unit or an OEM interface processor with conventional
The “High” position on the “Input Voltage” switch selects an input sensitivity range between 800mV and 8V. This is useful for certain high- output preamp level signals as well as speaker- level output from source units and
small amplifiers.
To use
The output of the amplifier will decrease for a given input voltage when the “Input Range” switch is placed in the “High” position.
Conversely, the output will be higher with the switch in the “Low” position. While this may sound
AMPLIFIER CONTROLS
1)“Input Sens.”: Once the appropriate “Input Voltage” range has been selected, the control labeled “Input Sens.” located in the “Amplifier Controls” section can be used to match the source unit’s output voltage to the input stage of the amplifier for maximum clean output. Rotating the control clockwise will result in higher sensitivity (louder for a given input voltage). Rotating the control counter- clockwise will result in lower sensitivity (quieter for a given input voltage.)
|
| Filter Freq. (Hz) | ||
Input Sens. | LP Filter |
| 65 | |
55 | 80 | |||
|
| |||
|
| 45 | 100 | |
|
| 40 | 200 |
To properly set the amplifier for maximum clean output, please refer to Appendix A (page 12) in this manual. After using this procedure, you can then adjust any or all “Input Sens.” levels downward if this is required to achieve the desired system balance.
Do not increase any “Input Sens.” setting for any channel(s) of any amplifier in the system beyond the maximum level established during the procedure outlined in Appendix A (page 12). Doing so will result in audible distortion and possible speaker damage.
Filter Controls
Most speakers are not designed to reproduce the full range of frequencies audible by the human ear. For this reason, most speaker systems are comprised of multiple speakers, each dedicated to reproducing a specific frequency range. Filters are used to select which frequency range is sent to each section of a speaker system. The division of frequency ranges to different speakers can be done with passive filters (coils and/or capacitors between the amplifier outputs and the speakers), which are acceptable and commonly used for filtering between mid- range speakers and tweeters. Filtering between subwoofer systems and satellite speaker systems is best done with active filters, which cut off frequency content at the input to the amplifier. Active filters are more stable than passive filters and do not introduce extraneous resistance, which can degrade subwoofer performance.
The active filter built into the A1400 can be used to eliminate potentially harmful and/or undesired frequencies from making their way through the amplifier sections to the speaker(s). This serves to improve tonal balance and to avoid distortion and possible speaker failure. Correct use of these filters can substantially increase the longevity and fidelity of your audio system.
The A1400 employs a sophisticated, variable,
2)Filter Operation: The
200 Hz via the “Filter Freq.” control knob and features the ability to select between a moderate “12dB” per octave or a steep “24dB” per octave slope via the “Mode/Slope” switch.
Depending on the subwoofer system and the vehicle, different slopes may be required to produce a smooth transition to the mid- bass speakers in the system. Experiment to find the slope which best matches the acoustic requirements of your system.
6 | JL AUDIO A1400 | JL AUDIO A1400 | 7 |