JL Audio ACS112LG-TW1 Active Subwoofer Enclosure

The JL Audio ACS112LG-TW1 is an active subwoofer enclosure designed for in-car audio systems. Its integrated amplifier operates at 400 W RMS into a 0.25 Ω load. RCA and high-level inputs allow the enclosure to be connected to different types of car audio sources.

The shallow enclosure is useful when every centimetre of boot space matters. Because the amplifier is already integrated, there is no need to find a separate power amplifier and then match it with a suitable subwoofer enclosure.

Enclosure and installation location

The slot-ported enclosure measures 533 mm wide, 343 mm high and 168 mm deep. Before installation, check more than the dimensions of the intended mounting area. Additional clearance must be left for the connectors, wiring and port opening.

The low-profile design helps make more practical use of limited space inside the vehicle. The enclosure weighs 13.24 kg, so it must be installed on a stable surface. A secure method of fastening the enclosure should also be planned before installation.

The exterior is finished in black carpet. An included black steel-mesh grille covers the speaker. This grille is especially useful when the enclosure is installed in a boot that is also used for carrying luggage or other items.

Signal connections

The RCA input accepts a signal from 70 mV to 1.40 V RMS. Choose this connection when the car stereo or audio processor has a suitable line-level output. It allows the source signal to be sent directly to the enclosure’s integrated amplifier.

The high-level input accepts a signal from 280 mV to 5.4 V RMS. It is useful when the existing system does not provide a suitable RCA output. In that situation, the signal can be taken from a speaker channel without installing a separate line-output converter.

The selected source must fall within the voltage range specified for the chosen input. Do not use both connection methods for the same signal. Select the input according to the output available from the stereo or audio processor.

Power installation requirements

8 AWG copper cables are recommended for both the power and ground connections. The specified conductor size is important throughout the entire circuit, so copper cables of the same standard should be used for both connections.

The circuit requires a 30 A ATO or ATC fuse. Use the stated fuse rating and type. Select the power cables according to the actual cross-sectional area of their copper conductors, rather than judging them only by the thickness of the outer insulation.

Filter and polarity adjustment

The integrated signal processing provides a low-pass filter only. Its adjustment range is 50-200 Hz, with a slope of 12 dB per octave. The filter limits the higher frequencies sent to the subwoofer enclosure.

Choose an initial filter setting based on the frequency range reproduced by the vehicle’s main speakers. Smaller speakers will generally require a higher filter frequency. With larger speakers that extend further into the lower frequencies, adjustment can begin from a lower setting.

Complete the final adjustment while listening from the driver’s seat. The bass should complement the main speakers instead of sounding like a separate source. Setting the filter frequency too high can make the enclosure’s location inside the vehicle more noticeable.

The output polarity switch helps integrate the subwoofer enclosure with the rest of the audio system. Compare both switch positions while listening to the same recording. Keep the position that produces a smoother, fuller sound through the frequency range where the subwoofer and main speakers overlap.

Level control

An optional RBC-1 remote level controller can be connected to the enclosure. It allows the bass level to be adjusted from a position within the driver’s reach. This is convenient when recordings vary in level or when moving between different styles of music.

The RBC-1 is an optional accessory and is not included. The main gain level should first be set correctly during installation. Use the remote controller for everyday adjustments rather than as a way to compensate for an unsuitable initial setup.

Technical specifications

FAQ

Which input should I use with my car stereo?

Use the RCA input if the stereo has a suitable line-level output. Choose the high-level input when taking the signal from a speaker channel. In either case, the source output voltage must fall within the range specified for the relevant input.

Do I need a separate power amplifier?

No. The enclosure already contains a 400 W RMS amplifier. The stated 0.25 Ω impedance is the nominal impedance of the integrated system itself.

How should I begin adjusting the low-pass filter?

Begin with a setting that corresponds to the lower reproduction limit of the main speakers. Then make further adjustments while listening from the driver’s seat. The available adjustment range is 50-200 Hz.

What is the polarity switch used for?

It helps align the operation of the subwoofer enclosure with the main speakers. Try both positions and select the one that produces the smoother sound.

How much installation space is required?

The enclosure itself requires at least 533 × 343 × 168 mm of space. Additional clearance must be allowed for the wiring, connectors and port opening.

Is the RBC-1 controller included?

No, the RBC-1 is not included. An optional RBC-1 remote level controller can be connected to the enclosure, allowing convenient bass-level adjustment from the driver’s position.

Is this enclosure intended for a home stereo or cinema system?

No. This model is designed for a car audio system. Its inputs, power installation requirements and enclosure shape are intended for automotive audio equipment.