EA-AMP-12D-45A Installation Manual
Pg. 9
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5. System Design Considerations
5.1. Speaker Placement
The EA-AMP-12D-45A amplifier output zones are arranged in pairs of left and right channels. Each pair can be
bridged for one mono channel. For most applications, a pair of stereo speakers properly placed in a room (or a
single dual voice coil speaker playing stereo audio) will sound better than a mono bridged output feeding one
bigger speaker unless the extra power is needed for a high wattage speaker or a long wire run.
When planning speaker locations, check with the speaker manufacturer for the best possible layout for the
models used. As a general guideline, try to spread locations evenly to accommodate both the room dimensions
and the overall balance of each channel (left and right). Consider using a bridged output for large outdoor
speakers, or if a non-powered subwoofer will be attached to an output. Full information on speaker wiring and
connections can be found in Section 6.2 Speaker Connections and Setup.
5.2. Volume Control
For fine-tuning output zone volume levels after installation, see Section 6.5 Zone Volume Calibration.
5.2.1. No Inline Volume Controls
When setting up a system without inline volume controls, make sure that the source used has adjustable volume for
the output connected to the amplifier. The system volume will be controlled by setting the level of the source output.
Any zones playing that input will change volume together. Each zone level can be calibrated individually to a degree
by changing its LEVEL knob.
This setup is optimal for zones utilizing dedicated input sources, as the volume is usually much more adjustable than
if an inline volume control were being used, and other zones aren’t affected by source volume changes.
5.2.2. With Inline Volume Controls
In systems where each output zone is wired with an inline volume control between the amplifier and the speakers,
volume can be adjusted in each zone individually no matter what the other zones are set to. Source volume and
zone levels are typically fine-tuned during setup, and the end user adjusts each zone at the volume control during
normal use.
If a multi-source setup is used (as in Section 6.7 Multi-source Multi-Room Audio) there will be full control of both
source selection and volume in every zone. Combined with an automation system for remote control of sources, this
setup allows for the most control possible in a multi-room audio application using the EA-AMP-12D-45A.
5.3. Control Method
When deciding on the control method for the amplifier, consider the sources in use and the purpose of the amplifier
on the job. See Section 6.4 Amplifier Power Control for full instructions on power control setup and operation.
• Using the front Power button (Power ON mode) will allow manual control at all times, and is useful for
installations where the audio system will be powered on and shut down regularly at the equipment. Use this
mode if the system is always set by the user at the equipment.
• Avoid using Power ON mode for jobs where a remote is typically used to control the system, since the
amplifier would be required to be on at all times. The amplifier could be set to Stand-by inadvertently which
may confuse the user into thinking there is a problem.
• When the system will be controlled from anywhere but at the equipment, try to use the TRIGGER DC 12V
or AUTO mode for amplifier power control. These options are the most reliable since the amplifier will be
automated to turn on whenever it is needed.
• When using a source that remains on at all times, using the AUTO mode for amplifier control could keep the
unit powered at all times due to either signal or noise on the line from the source. This can be avoided by
turning the source off completely when not in use, or by using a 12 volt trigger instead.
