User`s guide

LS4

24dB/Octave Active Stereo Crossover

How to Use the Crossover:

For Bi-Amping in a Single Enclosure:

For bi-amping in a single enclosure, the basic connections are illustrated below.

Connect the line level output of your source (mixer, preamp, etc.) to the CHANNEL ONE BALANCED INPUT of the LS4 (A).

Connect the LS4’s CHANNEL ONE LOW OUT to the input jack of the amplifier which will be used to power the low fre-

quency section of the enclosure (B). Connect the LS4’s CHANNEL ONE HIGH OUT to the input jack of the amplifier

which will be used to power the upper frequency section of the enclosure (C). (Hint: Label the amplifiers “low freq

amp” and “high freq amp” to avoid confusion.) Connect the amplifiers to the respective input jacks of the enclo-

sure. Repeat for channel two if used.

Before you operate your system, set the appropriate crossover frequency. Check the speaker manufacturer’s specifi-

cations for minimum crossover frequency and power handling! This information is usually printed on or near the

input jackplate. Most manufacturers of horn loaded compression drivers will list the lowest recommended

crossover frequency accompanied by the maximum power the unit will handle with different horn types. A good

rule of thumb is to stay above the recommended frequency. In addition, when using a crossover between a cone

type loudspeaker and a horn, pay attention to the full range dispersion pattern. For example, a typical 15” diameter

loudspeaker will begin to beam above 800Hz – that is, at frequencies above 800Hz its dispersion angle begins to

decrease, causing a drop in SPL off axis. (See the illustrations on the following page.) The table on the following

page shows different diameter cone loudspeakers and their typical dispersion characteristics. If the horn you are

using has a horizontal dispersion of 90˚, then a crossover point should be selected to provide a smooth transition

from the cone speaker to the horn. This will insure a predictable off-axis response (refer to the illustration on the

following page).

WARNING: Do not exceed the lower crossover frequency limits of your high frequency component or it may get

damaged!

IMPORTANT NOTE: Whether you are bypassing the internal passive

crossover of an existing enclosure or building your own system, care

must be taken not to exceed the limitations of the speaker components!