Marshall AR-AM4-BG-2 User Manual [EN]

Broadcast A/V Division

AR-AM4-BG-2

Multichannel Analog Audio Monitor

User Manual

[Firmware Version 0.43]

AR-AM4-BG-2 Manual

Table of Contents

1. Features

2. Package Contents

3. Front Panel Description

4. Control Button Detail

5. Rear Panel Description

6. Operation

7. Metering and Indicators

8. Software - Control App

9. Serial Connection

10. Operation

03

03

04

05

05

06

06

07

08

09

1. Features

High Performance Audio

• Matches or exceeds many larger 2RU designs

• Enough “punch” for the noisiest server rooms

Multiple Inputs

• 4 Analog XLR Balanced – 4 Inputs x 2 Channels Each

Outputs

• 1 Analog XLR Balanced - 2 Channel

LED VU Display

• Provides active indication of audio input activity

Controllable via RS-232 Serial

• Remote control application downloadable from Marshall website

• Select sources, mute, solo, volume, etc.

11. Updating

12. Specifications

Warranty

10

11

12

Compact 1RU Design Saves Rack Space

• Minimum size

• Low power consumption, low heat into rack

• Compact size which does not compromise audio volume

2. Package Contents

• AR-AM4 Main Chassis

• 12-volt Universal Power supply (120/240V – 50/60Hz)

• Remote Control Application (free download from website)

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AR-AM4-BG-2 Manual

3. Front Panel Description

1. Speakers

Provides sound from two channels except when Solo buttons are pressed

2. Headphone Jack

3. Volume Knob / Mute Button

Turn the knob to adjust the sound level out of both speakers

Press in on the knob to instantly mute the speaker

4. Headphone Jack

Designed to accept stereo headphones with 3.5mm plug

5. Input and Solo Left/Right Select Buttons

Select either channel for monitoring from both speaker

6. LED VU Meter Display

7. LED Indicator Lights

• Phase – Indicates audio in-phase / out-of-phase conditions

4. Control Button Detail

1. Input Select

Press one of these four buttons to monitor the corresponding input

2. Solo Left & Solo Right

Press isolate either the left or right channel only

Note: Sound will come out of both speakers when Solo is selected but will originate from a
single source.

• Mute – Indicates when speakers have been muted

8. Balance Knob

Select either speaker or adjust balance between them

5. Rear Panel Description

1. Power Switch

2. 12-Volt DC Power Input – Coaxial, Center Positive

3. RS-232 Serial Control 9-pin D-Sub Port and Loop Out

4. Analog Balanced XLR +4dBu Output Pair (2 channels)

5. Four Analog Balanced XLR +4dBu Input Pairs (8 channels)

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AR-AM4-BG-2 Manual

6. Operation

Controls on the AR-AM4-BG-2 are designed to be user-friendly and straight-forward. Simply press
one of the four Input buttons to select the desired source, then adjust the volume knob to the
desired listening level. Pressing in on the Volume knob will instantly mute both speakers. A red LED
next to the Balance knob will light whenever the audio is muted.

Press either Solo Left or Solo Right to hear sound from only the Left or Right channel. The selected
source will be heard from BOTH speakers.

Adjust the Balance knob to hear the sound from just one speaker or to match Left and Right sound
levels. A slight detent “bump” can be felt as the knob is rotated through the middle point to indicate
that balance is centered.

Note: The audio from the two Output connectors on the rear panel is affected only by the four input
selector buttons. Other controls such as Solo, Volume, Balance, and Mute will not affect the Output.

7. Metering and Indicators

8. Software - Control App

Download

A free application is available for download from the Marshall Electronics website at:

www.marshall-usa.com/

The AR-AM4-BG-2 may be operated and configured from a Windows® computer by a Serial (RS-

232) link.

Download, unzip and extract the file “AR-AM4-BG-2.exe” to a folder or to the desktop. Double­click the file and it will open immediately and look like this:

The front panel has two LED VU meters. They are calibrated to indicate “0” when the audio input is
+4dBu broadcast standard level.

(+4dBu is defined as a 1KHz tone at 1.23 Volts RMS or 3.47 Volts peak-to-peak across pins 2 & 3
of the input XLR connector).

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9. Serial Connection 10. Operation

AR-AM4-BG-2 Manual

To control the AR-AM-4 using an RS-232 serial link, first select the port number. The correct port
number will likely be the one with the highest numeric value.

Note: A serial connection will require either a serial port on the PC or a serial adapter device most
likely attached to the computer by USB. The most common connector type will be a 9-pin D-Sub
similar to the one on the back of the AR-DM51-B. When that is the case, a successful connection
can be made by using a straight through cable (not a “Null Modem Cable”). It is only necessary to
make the three connections shown here.

Computer AR-DM51-B

Pin 2 ---------------- Pin 2 (Tx)

Pin 3----------------- Pin 3 (Rx)

Pin 5 ---------------- Pin 5 (Ground)

Once a connection has been established between the control application and the AR-AM4-BG-2,
operation is simply a matter of clicking on the desired functions.

All of the front panel functions can be operated through the control application screen with the
exception of the Balance control.

In the example below, Input 1 has been selected, the speakers are unmuted and the sound from the
Right channel is being heard from both speakers.

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AR-AM4-BG-2 Manual

11. Updating

When a firmware update is issued for the AR-AM4-BG-2, it will be posted on the www.Marshall­USA.com website. Simply download the file and save it to a location on the computer.

the Firmware Update button starts the update process and the window shown below appears.

Click on “Load File”, then browse to the location of the saved update file.

Next, click on “Burn” which will transfer the file to the AR-AM4-BG-2 and start the update process.
Do not turn off the unit until the update has completed.

12. Specifications

Feature AR-AM4-BG-2

Interfaces

Audio Inputs Analog Balanced x 8 XLR Female

Audio Outputs Analog Balanced x 2 XLR Male

Headphone Output

Serial Control Connector

Controls and Displays

Input Select Four buttons, each selects one input pair

Solo Left, Solo Right

Volume Knob

3.5mm Stereo Phone Jack (plugging in
headphone mutes speakers)

9-pin D-Sub supports RS-232 control and

updates

Select to monitor Left or Right channel

individually

Rotate to change speaker volume level, Push

knob in to Mute speakers

Balance Knob

Phase LED

VU Meter

Mechanical & Electrical

Housing Metal enclosure

Dimensions (Depth Includes Connectors) [H x
W x D]

Weight 7.3 lbs / 3.3 Kg

Mounting

Included Power supply

DC Power consumption

Rotate to change the volume ratio between left

and right speakers

Green = Left / Right In-Phase, Red = 180°

Phase, Blinking = Changing Phase

“0” mark indicates +4dBU (1.23 Volts RMS,

3.47 Volts P-P) input level

1.75” X 19” x 8.5” / 4.45 cm x 48.25 cm x 21.6
cm

Chassis includes “ears” for standard 19” rack

mount

12 Volts DC, 5 Amps Coaxial Connector,

Center Positive Accepts 100 – 240 Volts AC,

50/60 Hz Line

3 Watts at Typical Listening Level, Less than 2

Watts Silent

cont. on page 12

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Operation temperature 0~40°C [32~104°F]

Storage temperature -20~60°C [-4~140°F]

ESD protection

Relative humidity 20~90% RH [no condensation]

Human body model — ±15kV [air-gap

discharge] & ±8kV [contact discharge]

Warranty

Marshall Electronics warranties to the first consumer that this device will, under normal use,
be free from defects in workmanship and materials, when received in its original container, for
a period of two years from the purchase date. This warranty is extended to the first consumer
only, and proof of purchase is necessary to honor the warranty. If there is no proof of purchase
provided with a warranty claim, Marshall Electronics reserves the right not to honor the warranty
set forth above. Therefore, labor and parts may be charged to the consumer. This warranty
does not apply to the product exterior or cosmetics. Misuse, abnormal handling, alterations or
modifications in design or construction void this warranty. No sales personnel of the seller or
any other person is authorized to make any warranties other than those described above, or to
extend the duration of any warranties on behalf of Marshall Electronics, beyond the time period
described above.

Due to constant effort to improve products and product features, specifications may change
without notice.

20608 Madrona Avenue, Torrance, CA 90503

Tel: [phone] • Fax: [phone]

www.marshall-usa.com

[e-mail]

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