HR AMP-4840 User manual

User’s Manual
AMP-4840
40 Watt Audio Amplifier
with RS-232 and IR Control
UMA1272 Rev B
Order toll-free in the U.S. 800-959-6439
FREE technical support: 714-641-6607 or [email protected]m
Hall Research, 1163 Warner Ave. Tustin, CA 92780
www.hallresearch.com
CUSTOMER
SUPPORT
INFORMATION

d
40 Watt Audio Am
p
lifier with RS-232
© Copyright 2018 Hall Research, Inc.
3
Table of Contents
1.0 Introduction ................................................................................. 4
Features .................................................................................................4
2.0 Package Contents ........................................................................4
3.0 Connectors, Indicators, and Controls......................................5
3.1 Input Panel .................................................................................5
3.2 Output Panel...............................................................................6
3.3 Top Panel.................................................................................... 7
4.0 RS-232 Serial Control of Amplifier ..........................................7
5.0 Troubleshooting.......................................................................... 9
6.0 Specifications...............................................................................9
FCC Notice
This device complies with Part 15 of the FCC Rules. Operation is subject to the following
conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference even if it causes undesired operation.
This equipment has been desinged to comply with the limits for a Class A digital device,
pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable
protection against harmful interference when the equipment is operated in a
commercial environment. This equipment generates, uses, and can radiate radio
frequency energy, and if it is not installed and used in accordance with the instruction
manual, it may cause harmful interference to radio communications. Operation of this
equipment in a residential area is likely to cause harmful interference, in which case the
user will be required to correct the interference at his own expense.

AMP-4840
4© Copyright 2018 Hall Research, Inc.
1.0 Introduction
The AMP-4840 is a compact, economical and energy efficient (Class D) mono /
stereo audio amplifier with 3 inputs (2 line in and 1 balanced microphone).
Versatile design is compatible with dynamic, condenser or wireless
microphones with fully adjustable control options including RS-232, IR, and
front panel buttons. Functions include bridge connection, dual-mono, EQ
control, and microphone mixer.
The AMP-4840 is a perfect for classrooms, meeting rooms, boardrooms, sports
bars, and more.
Features
•Drives: 2x 20w @ 4 Ω or 2x 10w @ 8 Ω or 1x 40w @ 8 Ω in bridge mode
•Two stereo audio inputs, switchable by button, IR remote & RS-232
•Volume / Bass / Treble controllable by buttons, IR remote & RS-232
•MIC port supports balanced or unbalanced signals
•3.5mm jack line audio output with controllable volume
•Mono mix switch for summing left and right channels for driving mono
outputs
•Microphone input can be mixed with line input and each can be
controlled separately
•MIC input supports 48V phantom power, dynamic MIC and wireless MIC
•Auto noise squelch. Detects audio on inputs and mutes the output when
there is no input
•Does not have fans
2.0 Package Contents
(1x) AMP-4840 device itself
(1x) AC Adapter (24 VDC) Power supply
(1x) User’s Manual
Optional Accessories (sold separately)
IR Remote with IR Detector Cable

d
40 Watt Audio Am
p
lifier with RS-232
© Copyright 2018 Hall Research, Inc. 5
3.0 Connectors, Indicators, and Controls
3.1 Input Panel
The input panel is shown above. There are two audio inputs that are mixed
together they are the Mic In and Line In. The speaker output audio is a mix of
these two inputs. You can control the level of each used in the composite output
from the top panel as described below.
Within the Line input group, there are two inputs labeled A and B. Only one can
be active at a time based on the selection made from the top panel.
The microphone input is a balanced 3 terminal detachable screw-type
connector. There is a 3-position slide-switch next to the screw terminal to select
the type/level of the Microphone input signal as described below:
•Phantom: Use this position for microphones requiring phantom power
such as condenser Mics. Typical input level for this mode is (-48 dBV, -
45 dBu) or around 4 mv rms sine wave.
•Dynamic: This position is used for dynamic microphones with low-level
outputs. Typical input level for this mode is (-60 dBV, -58 dBu) or
around 1 mv rms sine wave.
•Wireless: This position is for Mics that output full consumer line level
outputs, such as wireless microphone receive outputs.
The External Control group includes a screw terminal for RS-232 (please see
related section below), and IR jack for connection of optional IR detector cable.
The Speaker Mode is a 3-position slide switch that functions as described
below:
•Stereo: This position is used for connecting two 8 Ω or 4 Ω speakers.
The Left and Right channel audio separations are intact and you will
get stereo output sound.