Introduction

The JBL Harman Subwoofer Powered A120P is a powerful audio solution designed to enhance your home theater experience. Featuring a 12-inch polycellulose low-frequency woofer, it delivers robust bass performance with a dynamic power output of 500 watts. The subwoofer's frequency response ranges from 32Hz to 150Hz, ensuring deep, rich sound that complements any audio setup. Its rear-firing tuned ports and adjustable crossover settings allow for customizable integration with other speakers. Priced at approximately $299.95, the A120P offers exceptional value for audiophiles seeking to elevate their sound system.

A high-performance transducer and built-in amplifier that delivers the powerful, dynamic and accurate low-frequency performance that makes your film soundtracks and music come alive. And with adjustable crossover, phase controls and automatic turn on/off, it is also simple to connect and set up.

We're confident that this JBL subwoofer will provide every note of enjoyment that you expect – and that when you think about purchasing additional audio equipment for your home, car or office, you will once again choose JBL products.

INCLUDED ITEMS

Note: Type of power plug varies by regions.

REAR-PANEL CONTROLS AND CONNECTION

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Power Mode:
When switched to 'Auto' position, the subwoofer will then be in Standby mode. It will automatically turn on when an audio signal is detected and will return to the Standby mode when no audio signal is detected after approximately 10 minutes. Setting this switch to 'On' keeps the subwoofer powered until Power Switch is turned 'Off.'
On/Standby LED:
When the Power Switch is in the 'On' position, this LED indicates whether the subwoofer is in the On or Standby state.
- When the LED glows blue, the subwoofer is turned On.
- When the LED glows red, the subwoofer is in the Standby mode.
Phase Switch:
This switch determines whether the subwoofer transducer's pistonlike action moves in and out in phase with the main speakers. If the subwoofer were to play out of phase with the main speakers, the sound waves from the main speakers could partially cancel out the sound waves from the subwoofer, reducing bass performance and sonic impact. This phenomenon depends in part on the placement of all the speakers relative to the listening position and to each other in the room.
Crossover Control:
This control determines the highest frequency at which the subwoofer reproduces sounds. The higher you set the Crossover control, the higher in frequency the subwoofer will operate and the more its bass will “overlap” that of the speakers. This adjustment helps achieve a smooth transition of bass frequencies between the subwoofer and the speakers for a variety of different rooms and subwoofer locations.
Volume:
Use this control to adjust the subwoofer's volume. Turn the knob clockwise to increase the volume; turn the knob counterclock-wise to decrease the volume.
Subwoofer (LFE Input):
Connect the subwoofer to the dedicated subwoofer / LFE output of a receiver/processor.
Power Switch:
Set this switch in the 'On' position to turn the subwoofer on. If you will be away from home, or will not be using the subwoofer for an extended period, set this switch in the 'Off' position to conserve energy.
Power Input:
After you have made and verified the subwoofer's input connection, plug the power cord into an active, unswitched electrical outlet for proper operation of the subwoofer.
DO NOT plug the power cord into the accessory outlets found on some audio components.

JBL Harman Subwoofer Powered A120P Specifications

12" 500 Watts powered subwoofer

12" (305mm) Polycellulose Low-Frequency Woofer
Power: 250W RMS (500W Dynamic)
Frequency Response: 32Hz - 150Hz
Crossover Frequencies: 50Hz – 150Hz (variable) 24dB/octave
Controls: Auto Power, Crossover, Level, Phase
Input: 1 x Line-Level LFE Input
Enclosure Type: Bass-Reflex via Rear-Firing Tuned Ports
Power Requirement: 120V, 60Hz (US) 220-230V, 50/60Hz (EU)
Power Consumption (Idle/Full/Power): <0.5W (standby) / 335W/2A (max – 230V) / 335W/4A (max – 120V)
Dimensions (W x D x H): 390 x 420 x 395 mm
Weight: ?? lbs (?? kg)

Description

The JBL Harman Subwoofer Powered A120P is built with durability and performance in mind. The 12-inch woofer is housed in a sturdy enclosure that helps to minimize distortion and ensure clear, deep bass. The subwoofer features a powerful amplifier that delivers consistent performance even under demanding conditions. With its adjustable crossover frequency, you can easily integrate it into your existing sound system to achieve optimal sound quality.

The A120P also includes multiple input options, making it versatile enough to connect to various audio sources. Whether you're connecting it to a mixer, an audio interface, or directly to a receiver, this subwoofer is designed to be compatible with a wide range of setups.

PLACING THE SUBWOOFER

The performance of a subwoofer is directly related to its placement in the listening room and its physical position relative to the other speakers in the system.

While it is true that in general our ears do not hear directional sounds at the low frequencies where subwoofers operate, when installing a subwoofer within the limited confines of a room, the reflections, standing waves and absorptions generated within the room will strongly influence the performance of any subwoofer system. As a result, the specific location of the subwoofer in the room does become important to the amount and quality of bass that is produced.

For example, placing the subwoofer next to a wall generally will increase the amount of bass in the room; placing it in a corner (1) generally will maximize amount of bass in the room. However, corner placement can also increase the destructive effect of standing waves on bass performance. This effect can vary depending on the listening position – some listening positions may yield very good results while others may have far too much (or too little) bass at certain frequencies.

In many rooms, placing the subwoofer along the same plane as the left and right speakers (2) can produce the best integration between the sound of the subwoofer and that of the left and right speakers. In some rooms, the best performance could even result from placing the subwoofer behind the listening position (3).

We strongly recommend that you experiment with placement before choosing a final location for your subwoofer. One way you can determine the best location for the subwoofer is by temporarily placing it in the listening position and playing music with strong bass content. Move around to various locations in the room while the system is playing (putting your ears where the subwoofer would be placed), and listen until you find the location where the bass performance is best. Place the subwoofer in that location.

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CONNECTING THE SUBWOOFER

TO A RECEIVER OR PREAMP/PROCESSOR WITH A LOW-PASS FILTERED DEDICATED SUBWOOFER OUTPUT (LFE)

Receiver/Processor

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Be sure to turn the Crossover on the subwoofer fully clockwise when using this type of connection. This type of setting bypasses the subwoofer's internal crossover and uses your receiver or processor's crossover.
Check your receiver or processor menu settings and set the subwoofer selection to 'On' or 'Yes.' Please be sure to review the owner's manual for your receiver or processor for more information on speaker setup and configuration.

TO A RECEIVER OR PREAMP/PROCESSOR WITH PREAMP OUTPUTS

Receiver/Processor

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We recommend setting the subwoofer's Crossover setting to 80Hz for mid-sized speakers, higher for smaller (satellite) speakers, and lower for larger floorstanding speakers.

OPERATING THE SUBWOOFER

TURNING THE SUBWOOFER ON AND OFF

Set the subwoofer's Power Switch to the 'On' position. Now set the subwoofer's Power Mode to the 'Auto' position. The subwoofer will automatically turn itself on when it receives an audio signal, and it will go into Standby mode after it has received no audio signal for approximately 10 minutes. The subwoofer's LED will glow blue when the subwoofer is on and will glow red when the subwoofer is in Standby.

If you will not be using the subwoofer for an extended period – for instance, if you're going on vacation – set the Power Switch to the 'Off' position.

Setup Guide

Setting up the JBL Harman Subwoofer Powered A120P is straightforward and can be completed in a few steps:

Unpack and Position: Carefully unpack the subwoofer and place it in your desired location. Ensure it is away from any walls or corners to avoid resonance issues.
Connect Inputs: Connect the subwoofer to your audio source using the appropriate inputs (XLR, TRS, or RCA). Make sure to match the signal type (balanced or unbalanced) with the correct input.
Adjust Crossover Frequency: Adjust the crossover frequency to match your main speakers' frequency response for seamless integration.
Power On and Test: Turn on the subwoofer and test the sound to ensure everything is working correctly and adjust settings as needed.

SUBWOOFER ADJUSTMENTS

CROSSOVER

The Crossover control adjusts the subwoofer's built-in low-pass filter crossover between 50Hz and 150Hz. The higher you set the Crossover control, the higher in frequency the subwoofer will operate and the more its bass will 'overlap' that of the speakers. This adjustment helps achieve a smooth transition of bass frequencies between the subwoofer and the speakers for a variety of different rooms and subwoofer locations.

To set the Crossover control, listen for the smoothness of the bass. If the bass seems too strong at certain frequencies, try a lower Crossover control setting. If the bass seems too weak at certain frequencies, try a higher Crossover control setting.

VOLUME

Use the volume control to set the subwoofer's volume. Turn the knob clockwise to increase the subwoofer's volume; turn the knob counterclock-wise to decrease the volume. Once you have balanced the subwoofer's volume with that of the other speakers in your system, you shouldn't have to change the volume control setting.

Notes on Setting Subwoofer Volume:

Sometimes the ideal subwoofer volume setting for music is too loud for films, while the ideal setting for films is too quiet for music. When setting the subwoofer volume, listen to both music and films with strong bass content and find a 'middle ground' volume level that works for both.
If your subwoofer always seems too loud or too quiet, you may want to place it in a different location. Placing the subwoofer in a corner will tend to increase its bass output, while placing it away from any walls or corners will tend to lessen its bass output.

PHASE

The Phase switch determines whether the subwoofer driver's pistonlike action moves in and out in phase with the speakers. If the subwoofer were to play out of phase with the speakers, the sound waves from the speakers could partially cancel out the waves from the subwoofer, reducing bass performance and sonic impact. This phenomenon depends in part on the placement of all the speakers relative to each other and the listener(s) in the room.

Although in most cases you should leave the Phase switch in the 'Normal' position, there is no absolutely correct setting for the Phase switch. When the subwoofer is properly in phase with the speakers, the sound will be clearer and have maximum impact, and percussive sounds like drums, piano and plucked strings will sound more life-like. The best way to set the Phase switch is to listen to music that you know well and to set the switch in the position that gives drums and other percussive sounds maximum impact.

USING THE SUPPLIED CARPET SPIKES

Four metal spikes are supplied for use when you place the subwoofer on a carpeted surface. Do not use these spikes when placing subwoofer on non-carpeted surfaces.

To insert the spikes:

Gently lay the subwoofer on its side (not its front or back) on a soft, nonabrasive surface.
Screw each spike into the threaded insert in each foot. Make sure all four spikes are screwed in completely for stability.

Note: NEVER drag the subwoofer to move it. Always carefully lift the subwoofer and carry it to its new location.

Troubleshooting

If you encounter any issues with your JBL Harman Subwoofer Powered A120P, here are some common problems and solutions:

No Sound Output: Check that the subwoofer is turned on and that all connections are secure and correctly matched.
Distortion or Hum: Ensure that the subwoofer is placed away from any magnetic fields or electronic interference. Also, check for any loose connections.
Overheating: Make sure there is adequate ventilation around the subwoofer. Avoid placing it in a confined space or covering it with objects that could block airflow.

Instructions Warnings: Always handle the subwoofer with care to avoid damage. Never touch the woofer cone or attempt to repair the unit yourself.

JBL Harman Subwoofer Powered A120P Pros & Cons

Pros

High-Quality Sound: Delivers deep, clear bass with minimal distortion.
Versatile Connectivity: Multiple input options for easy integration with different audio systems.
Durable Construction: Built with high-quality materials to withstand regular use.
Adjustable Crossover Frequency: Allows for seamless integration with various speaker setups.

Cons

Weight and Size: May be heavy and large for some users, especially those with limited space.
Pricier Than Some Alternatives: Though competitively priced, it may still be out of budget for some users.
No Built-in EQ Controls: Users who prefer more detailed EQ settings may need additional equipment.

Customer Reviews

Customers have praised the JBL Harman Subwoofer Powered A120P for its powerful bass and reliability. Many have noted its ability to enhance their home theater and music listening experiences. However, some users have mentioned that it can be quite heavy and large, which may be a concern for those with limited space.

Common Complaints

A few users have reported issues with overheating when used in confined spaces. It is important to follow the manufacturer's guidelines regarding placement and ventilation.

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