Russound AB-3.2 User Manual

AB-3.2

Automatic Speaker Selector

Instruction Manual

Product Overview

The Russound AB-3.2 Automatic Speaker Selector is designed to provide automatic switching of two
amplified audio sources to a single pair of speakers. The AB-3.2 will automatically switch from the
main audio system (AMP A) to a local audio source (AMP B) when the local source is active. For
example, connect the speaker output of your Russound audio system to the AMP A input, your main
left and right home theater speakers to the speaker connectors, and the home theater main left and
right speaker output to the AMP B input. If you are listening to the Russound system (AMP A) and
turn on your home theater (AMP B), the AMP B audio will override the AMP A audio and the home
theater sound will be heard over the local speakers.

The AB-3.2 includes a sensitivity trigger adjustment to adjust the volume level where switching
occurs. It also includes a delay adjustment to prevent source switching during the absence of a
signal. The AB-3.2 is powered by a 12VDC detachable power supply (included). Country-specific
12VDC detachable power supplies can be substituted for use outside the U.S.

Installation

To minimize the possibility of picking up extraneous noise, it is recommended that the AB-3.2 be
located near the AMP B source.

Connect the whole-house or distributed audio system amplifier outputs to the AMP A Input
connectors. Connect the local source amplifier output (i.e., home theater output or local
receiver/music system) to the AMP B Input connectors. Connect the local speakers to the Speaker
Output connectors. Please observe signal polarity (+/-) and left/right channel orientation on all
connections. Connect the 12VDC power supply to the power input jack and plug the supply into a
non-switched AC outlet. The Power LED should light to indicate that the AB-3.2 is getting voltage
from the power supply and is ready for use.

Sensitivity Setup

Set the trigger control approximately halfway (12 o’clock) and set the delay to minimum (fully
counterclockwise). Turn on the local source and set the volume to a normal listening level. The AB-

3.2 should switch to the AMP B Input and you will hear the local source audio through the
speakers. The green LED on the AB-3.2 should also be on to provide a visual confirmation that the
AB-3.2 has switched to the AMP B Input. The AB-3.2 may also begin to switch back to the AMP A
Input during pauses and silent periods in the programming from AMP B (this is normal and is
adjusted in the Delay Setup section). Gradually reduce the volume from the AMP B source until you
reach the minimum listening level you want for this source. If the AB-3.2 switches back to AMP A
while you are doing this (i.e., LED turns off and speakers are silent), adjust the sensitivity trigger
control until the AMP B source is selected once again. It’s best to perform this adjustment with a
program which has some continuous signal source (i.e., shopping channel on TV), as pauses in the
signal will cause the AB-3.2 to switch back to the AMP A Input. If this on/off switching is too
distracting, you can increase the delay control setting to compensate.

Delay Setup

The mid-range setting of the delay control provides a delay of approximately 10 to 15 seconds. This
should be a good setting for most installations. If you use the AB-3.2 primarily at lower volume
levels you will need to add more delay to prevent the AB-3.2 from incorrectly switching back to the
AMP A Input during quiet periods in the programming from AMP B. Adjust the Delay control
clockwise to increase the delay time and counterclockwise to reduce the delay time.

Note: If AB-3.2 relays continually click, adjust the trigger control to less than 1/4-turn or until relays
stop clicking.