JBL G400 (01) PDF Document

For the best stereo reproduction, the two loudspeaker systems should be placed an equal distance from your listening position and separated so that the angle between them, at the listening position, is between 40 and 60 degrees. For example, if your listening position is 8 to 12 feet (2.5 to 4 m) from each speaker, the two systems should be about 8 feet (2.5 m) apart.

Placing the loudspeaker in a corner or against a wall will result in the strongest (but not necessarily the most accurate) bass. If possible, because the JBL G400 is a G model that is ported on the back, it should not be placed closer than 12 inches (305 mm) from the wall behind it.

For the best stereo imaging, it is recommended that the systems be placed so that the high frequency transducers are positioned approximately at ear level of a seated listener.

JBL loudspeakers are highly efficient and produce reasonable volume levels with little amplifier power. However, using a small amplifier to obtain desired volume levels may lead to overdriving the unit and generating high distortion that can damage the loudspeaker. For the best performance, an amplifier should be selected with an output rating that is greater than the maximum power that will be used. Do not exceed the maximum recommended amplifier power for the specific loudspeaker model (refer to specifications).

Use two-conductor insulated wire to connect your loudspeaker systems to a receiver or amplifier. #16 AWG wire is recommended as a minimum size. If your speakers are more than 30 feet (10 m) from your receiver or amplifier, use larger diameter wire.

1. First determine the distance between the most distant speaker.

2. Now make the hookup wires for both speakers this length, even if one loudspeaker is much closer to your amplifier than the other. This will help maintain proper signal balance.

3. Strip off 3/8″ of insulation from both ends of each conductor.

4. Twist each set of thin wires into a tightly-bunched spiral.

5. Identify a visual difference between the two conductors of each molded pair of speaker wire (e.g., different color, strand of yarn, raised ribs, or printed “+” marking) to ensure proper polarity.

The terminals located on the back of the loudspeaker system accept bare wire or dual banana plugs. To connect bare wire, push down on the button below the terminal and insert the wire through the hole.

For each channel, connect the red terminal on the loudspeaker to the red or (+) connection terminal on the receiver or amplifier, and the black to the black or (–). Connecting in this manner ensures the speakers are in phase.

Check the following tips:

1. Ensure the Amp/receiver tape monitor button is not pushed in while using CD, FM, or phono inputs.

2. Check for a wrong speaker switch setting (“A” or “B” speaker output).

3. Verify that the sound source (CD, cassette deck, turntable) is turned on, activated, hooked up, and selected on the amp/receiver front panel.

1. Check if the balance control is turned all the way left or right.

2. Check if a speaker wire has become disconnected.

This may happen if a few strands of speaker wire are shorting out. Recheck the connections. Also, recheck the impedance requirements of the amp.

1. The polarity (+ & –) of one speaker may have been reversed relative to the other. Double check connections.

2. The speakers may be too far away from back and side walls or too far apart. Experiment again with speaker placement.

The loudspeaker cabinet may be cleaned with a slightly damp cloth. To remove dust from the grille cloth, use a vacuum with a brush attachment. Spots may be removed with a commercial spot remover. Do not use any cleaners or solvents on the speaker drivers themselves.

The grille is held in place by pins near the edges. To remove the grille, grasp it by both top and bottom edges and pull gently. To replace the grille, reposition it carefully and press gently at the corners. Do not push on the center area of the grille.