JL Audio HD900/5 owner manual Speaker Connector Plugs

Bridging Considerations Bridging is the practice of combining the

output of two amplifier channels to drive a single load. When bridged, each channel produces signals of equal magnitude, but opposite polarity. The combined output of the two channels provides twice the output voltage available from a single channel. The HD900/5 has been designed for bridging of its two main channel pairs without the need for input inversion adaptors.

The mono subwoofer channel cannot be bridged to another mono channel.

To bridge either pair of main channels, use the “Left +” and “Right –”speaker connectors only (the “Left –”and “Right +” remain unused). Then connect a mono signal to both left

and right RCA inputs for that channel pair. This requires an RCA “Y-Adaptor” (sold separately), because a bridged pair of channels requires that both amplifier channels of the bridged pair receive input. Connection of only one RCA input will result in reduced power output, increased distortion and can cause the amplifier to overheat.

When bridged, each channel pair will deliver optimum power into a 3-8Ω load. Operating bridged channel pairs into a load lower than 3Ω is not recommended.

Speaker Connector Plugs

There are three speaker connector plugs on the HD900/5: one for the front channels, one for the rear channels and one for the subwoofer channel.

To connect the speaker wires to the amplifier, unplug the speaker connector plugs from the amplifier chassis (pull back firmly) and back out the set screws on each connector plug, using the supplied 2.5 mm hex wrench. Strip 3/8 inch (10

mm)of insulation from the end of each wire and insert the bare wire into the receptacle on the speaker connector plug, seating it firmly so that no bare wire is exposed. While holding each wire in place, tighten each set screw firmly, taking care not to strip the head of the screw.

Speaker loads below 1.5Ω nominal per channel in stereo or 3Ω nominal in bridged mode are not recommended and may cause the amplifier output to distort excessively.

14 JL Audio - HD900/5 Owner’s Manual