background image

8

 

JL Audio

INPUT SENSITIVITY CONTROLS

The “Input Sens.” control is 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). The “Input Sens.” control 
is equipped with a LED “Clipping” trim ring to 
simplify the input sensitivity setting process. 

INPUT SECTION

PREOUTS

CH. 1&2

CH. 1&2 

(only)

CH. 3&4

Clipping

Clipping

 

To properly set the amplifier for maximum 

clean output, please refer to Appendix A (page 
14) in this manual. After using this procedure, 
you can then adjust the “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 14). 

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 each channel 

section of the JD400/4 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.

INPUT SECTION

PREOUTS

CH. 1&2

CH. 1&2 

(only)

CH. 3&4

Clipping

Clipping

 

Содержание JD 400/4

Страница 1: ...d dealer has the training expertise and installation equipment to ensure optimum performance from this product Should you decide to install the amplifier yourself please take the time to read this man...

Страница 2: ...horns sirens etc SERIAL NUMBER In the event that your amplifier requires service or is ever stolen you will need to have a record of the product s serial number Please take the time to enter that num...

Страница 3: ...least 1 inch 2 5 cm of space above the amplifier s outer shell to permit proper cooling Safety Considerations Your amplifier needs to be installed in a dry well ventilated environment and in a manner...

Страница 4: ...o longer than 36 inches 90 cm from the amplifier to the ground connection point In some vehicles it may be necessary to upgrade the battery ground wire See page 5 for important notice 7 Securely mount...

Страница 5: ...nded at the contact point to create a clean metal to metal connection between the chassis and the termination of the ground wire For optimal grounding we recommend the use of a JL Audio ECS master gro...

Страница 6: ...n on signal is not available in a system These allow you to operate the amplifier without having to locate a remote turn on lead at the source unit which can be very useful when interfacing the amplif...

Страница 7: ...vel signals High for speaker level signals The Low position on the Input Voltage switch selects an input sensitivity range between 200mV and 2V This means that the Input Sensitivity rotary control wil...

Страница 8: ...esigned 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 r...

Страница 9: ...e or better Tuning Hint If you are using the JD400 4 to drive a subwoofer system LP mode a component satellite speaker system HP mode or both 80 Hz is a good baseline Filter Freq Hz setting After prop...

Страница 10: ...voltage available from a single channel The JD400 4 has been designed for bridging of its channel pairs without the need for input inversion adaptors To bridge a pair of channels use the Left and Rig...

Страница 11: ...n off and the amplifier will return to normal operating mode 2 Flashing Constant Red The Protection LED also illuminates during over current conditions This may result in the LED flashing as it corres...

Страница 12: ...HF Level Req uired a source unit or processor with two pairs of stereo outputs Inp ut Connections the first stereo pair of source unit outputs is connected to the CH 1 Left and CH 2 Right inputs of t...

Страница 13: ...m the front of the vehicle B Subwoofer Level Control Only Req uired a source unit or processor with left right and dedicated subwoofer outputs Inp ut Connections The main stereo pair of source unit ou...

Страница 14: ...ou have disconnected the speakers before proceeding Play a track with the appropriate sine wave within the frequency range to be amplified at 3 4 source unit volume 6 Slowly increase the Input Sens co...

Страница 15: ...Hz 20 kHz noise bandwidth 84 dB referred to 1W A weighted 20 Hz 20 kHz noise bandwidth Frequency Response 12 Hz 22 kHz 0 1 dB Damping Factor 150 4 ohms per ch 50 Hz 75 2 ohms per ch 50 Hz Input Sectio...

Страница 16: ...ed To test for this problem jump the 12VDC wire to the Remote terminal to see if the amplifier turns on I hear a repetitive ticking or popping sound coming out of the speaker s Check the speaker wires...

Страница 17: ...unit while an appropriate test tone is played through the source unit disconnect the input cables from the amplifier prior to this test The frequency used should be in the range that is to be amplifie...

Страница 18: ...18 JL Audio INSTALLATION NOTES Use this diagram to document your amplifier s switch and control positions INPUT SECTIO CH 1 2 CH Clipping...

Страница 19: ...JD400 4 19 ON PREOUTS CH 1 2 only 3 4 Clipping...

Страница 20: ...t retail and no warranties whether express or implied shall apply to this product thereafter Some states do not allow limitations on implied warranties therefore these exclusions may not apply to you...

Отзывы: