AMX ALR-AEC-8 ALERO User manual

INSTRUCTION MANUAL
ALR-AEC-8 ALERO
8-CHANNEL MICROPHONE MIXER

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Alero 8-Channel Microphone Mixer Instruction Manual
ESD WARNING
To avoid ESD (Electrostatic Discharge) damage to sensitive components, make sure you are properly grounded before
touching any internal materials.
When working with any equipment manufactured with electronic devices, proper ESD grounding procedures must be
followed to make sure people, products, and tools are as free of static charges as possible. Grounding straps, conductive
smocks, and conductive work mats are specifically designed for this purpose. These items should not be manufactured
locally, since they are generally composed of highly resistive conductive materials to safely drain static discharges,
without increasing an electrocution risk in the event of an accident
Anyone performing field maintenance on AMX equipment should use an appropriate ESD field service kit complete with at
least a dissipative work mat with a ground cord and a UL listed adjustable wrist strap with another ground cord.
IMPORTANT SAFETY INSTRUCTIONS
1. READ these instructions.
2. KEEP these instructions.
3. HEED all warnings.
4. FOLLOW all instructions.
5. DO NOT use this apparatus near water.
6. CLEAN ONLY with dry cloth.
7. DO NOT block any ventilation openings. Install in accordance with the manufacturer's instructions.
8. DO NOT install near any heat sources such as radiators, heat registers, stoves, or other apparatus (including
amplifiers) that produce heat.
9. DO NOT defeat the safety purpose of the polarized or grounding type plug. A polarized plug has two blades with
one wider than the other. A grounding type plug has two blades and a third grounding prong. The wider blade or
the third prong are provided for your safety. If the provided plug does not fit into your outlet, consult an
electrician for replacement of the obsolete outlet.
10. PROTECT the power cord from being walked on or pinched, particularly at plugs, convenience receptacles, and
the point where they exit from the apparatus.
11. ONLY USE attachments/accessories specified by the manufacturer.
12. USE ONLY with a cart, stand, tripod, bracket, or table specified by the manufacturer, or sold with the apparatus.
When a cart is used, use caution when moving the cart/apparatus combination to avoid injury from tip-over.
13. UNPLUG this apparatus during lightning storms or when unused for long periods of time.
14. REFER all servicing to qualified service personnel. Servicing is required when the apparatus has been damaged
in any way, such as power-supply cord or plug is damaged, liquid has been spilled or objects have fallen into the
apparatus, the apparatus has been exposed to rain or moisture, does not operate normally, or has been
dropped.
15. DO NOT expose this apparatus to dripping or splashing and ensure that no objects filled with liquids, such as
vases, are placed on the apparatus.
16. To completely disconnect this apparatus from the AC Mains, disconnect the power supply cord plug from the AC
receptacle.
17. Where the mains plug or an appliance coupler is used as the disconnect device, the disconnect device shall
remain readily operable.
18. DO NOT overload wall outlets or extension cords beyond their rated capacity as this can cause electric shock or
fire.
19. Place the equipment near a main power supply outlet and make sure that you can easily access the power
breaker switch.
The exclamation point, within an equilateral triangle, is intended to alert the user to the presence of important operating
and maintenance (servicing) instructions in the literature accompanying the product.
The lightning flash with arrowhead symbol within an equilateral triangle is intended to alert the user to the presence of
uninsulated "dangerous voltage" within the product's enclosure that may be of sufficient magnitude to constitute a risk of
electrical shock to persons.

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Alero 8-Channel Microphone Mixer Instruction Manual
FCC AND CANADA EMC COMPLIANCE INFORMATION:
This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may
cause undesired operation.
NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits
are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate
radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications.
However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or
television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or
more of the following measures:
Reorient or relocate the receiving antenna.
Increase the separation between the equipment and receiver.
Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
Consult the dealer or an experienced radio/TV technician for help.
Approved under the verification provision of FCC Part 15 as a Class B Digital Device.
CAN ICES-3 (B)/NMB-3(B)
EU COMPLIANCE INFORMATION:
Eligible to bear the CE mark; Conforms to European Union Low Voltage Directive 2006/95/EC; European Union EMC Directive 2004/108/EC; European
Union Restriction of Hazardous Substances Recast (RoHS2) Directive 2011/65/EU; European Union WEEE (recast) Directive 2012/19/EU;
You may obtain a free copy of the Declaration of Conformity by visiting http://www.amx.com/techcenter/certifications.asp
WEEE NOTICE
ESD Warning: The icon to the left indicates text regarding potential danger associated with the discharge of static
electricity from an outside source (such as human hands) into an integrated circuit, often resulting in damage to the
circuit.
WARNING: To reduce the risk of f ire or electrical shock, do not expose this apparatus to rain or moisture.
WARNING: No naked flame sources - such as candles - should be placed on the product.
WARNING: Equipment shall be connected to a MAINS socket outlet with a protective earthing connection.
WARNING: This product is intended to be operated ONLY from the voltages listed on the back panel or the recommended, or included,
power supply of the product. Operation from other voltages other than those indicated may cause irreversible damage to the
product and void the products warranty. The use of AC Plug Adapters is cautioned because it can allow the product to be
plugged into voltages in which the product was not designed to operate. If the product is equipped with a detachable power
cord, use only the type provided with your product or by your local distributor and/or retailer. If you are unsure of the correct
operational voltage, please contact your local distributor and/or retailer.
WARNING: Do Not Open! Risk of Electrical Shock. Voltages in this equipment
are hazardous to life. No user-serviceable parts inside. Refer all servicing to
qualified service personnel.
CAUTION: Changes or modifications not expressly approved by the manufacturer could void the user's authority to operate this
device.
This appliance is labeled in accordance with European Directive 2012/19/EU concerning waste of electrical and
electronic equipment (WEEE). This label indicates that this product should not be disposed of with household waste. It
should be deposited at an appropriate facility to enable recovery and recycling.

Table o f C ont en ts
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Alero 8-Channel Microphone Mixer Instruction Manual
Table of Contents
Introduction ......................................................................................................1
Audio ................................................................................................................................ 1
Power Supply..................................................................................................................... 2
Hardware Description .......................................................................................3
Front Panel ........................................................................................................................ 3
Rear Panel ......................................................................................................................... 3
Connector Definitions....................................................................................................... 4
VC - Video Conferencing ......................................................................................................................... 4
Line In/Line Out ...................................................................................................................................... 4
PA Speaker Output.................................................................................................................................. 4
Microphone Inputs ................................................................................................................................. 5
Mute Group ............................................................................................................................................. 5
USB Port.................................................................................................................................................. 5
RJ-45 Connector ..................................................................................................................................... 6
Power Connector .................................................................................................................................... 6
Installation ........................................................................................................7
List of Supplies ................................................................................................................. 7
Placement......................................................................................................................... 7
Connections...................................................................................................................... 7
Connect to the Network.......................................................................................................................... 7
Connect Power........................................................................................................................................ 8
Connect Audio Conference Equipment .................................................................................................. 8
Connect Video Conference Equipment................................................................................................... 8
Microphone Connections........................................................................................................................ 9
Detect IP address ................................................................................................................................... 9
Configure Microphone Inputs ................................................................................................................ 9
Configure Input/Output Channels. ........................................................................................................ 9
Configuration ..................................................................................................10
Network Configuration ................................................................................................... 10
Reset Button ................................................................................................................... 10
Levels.............................................................................................................................. 11
Signal Levels ......................................................................................................................................... 11
Microphone Volume.............................................................................................................................. 11
Channel Volume.................................................................................................................................... 12
Signal Mixing .................................................................................................................. 12
Signal Levels ......................................................................................................................................... 12
Selection of Mixing Microphones (AMM).............................................................................................. 13
Signal Mixing......................................................................................................................................... 13

Table o f C ont en ts
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Alero 8-Channel Microphone Mixer Instruction Manual
Active Mute Groups .............................................................................................................................. 14
Microphone Settings ...................................................................................................... 15
Basic Configuration .........................................................................................16
Save and Load Settings ........................................................................................................................ 16
Firmware Upgrade ................................................................................................................................ 16
Factory Reset ........................................................................................................................................ 16

Introduction
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Alero 8-Channel Microphone Mixer Instruction Manual
Introduction
The Alero (FG1140-08) is an 8 channel microphone mixer with built in acoustic echo canceller. Alero acts as a USB audio device
with a capability to connect 3 analog input and 3 analog output channels. Alero also supports 2 channel mono line level speaker
signal outputs:
Line In 1 and 2 are stereo
Line Level to speaker is stereo
Audio
The product contains audio signal processing software with the following signal processing blocks:
Alero supplies full duplex communication without disturbing background noise in a telecommunication system. The microphone
input channels are automatically mixed with the AMM. The loudspeaker echo is removed from the microphone signals by the
modules AEC and RES. Noise reduction, equalization filters are applied to further improve audio quality. Comfort noise is added to
microphone channels to avoid a pumping noise level when the RES is working.
A flowchart of the signal processing modules for the microphone input is shown in FIG. 1.
After the microphone inputs have been mixed to one output it will be added to output channels in combination with input channels,
see Figure 2.
Processor Description
Automatic Microphone
Mixing (AMM)
The microphone input channels are automatically combined into one output channel. The
microphone mixing performs a selection of which channel to open, reducing overall noise level
and improving speech clarity compared with just adding all microphone channels.
Acoustic Echo Cancellation
(AEC)
Models the acoustic environment and removes the loudspeaker echo via adaptive filtering.
Residual Echo Suppression
(RES)
Additional suppression of acoustic echo while still maintaining full duplex performance.
Comfort Noise (CN) Noise with similar level and characteristics as the background noise is added to microphone
channels to avoid a pumping noise level when the RES applies damping to reduce echoes.
Noise Reduction (NR) Models the characteristics and level of the background noise and reduces the noise level on the
microphone channels.
Channel Equalization (EQ) Equalization filtering is applied for enhancing speech clarity and to compensate for
characteristics on connected devices.
Signal Mixer The processed microphone signal is added to the output channels in combination with the input
channels. It is possible to select the routing of input channels to output channels.
Volume Adjustment (VOL) Volume adjustment and mute functionality for all input and output channels without sudden
transitions. There are no artifacts such as clicks and pops when muting/unmuting a channel.
Signal amplification is performed without introducing amplitude clipping.
FIG. 1 Microphone Signal Processing Flowchart

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Alero 8-Channel Microphone Mixer Instruction Manual
Introduction
Power Supply
The Alero AEC requires the use of an external power supply. AMX recommends the following:
PSR4.4 - Power supply provides 4.4 A of DC power and is optional (ordered separately). It includes a 3.5 mm Phoenix
Connector with retention screws and a 6-foot (1.83 m) IEC po wer cord terminated with a grounded Edison plug for AC
input (U.S. only).
Refer to http://www.amx.com/products for further details.
FIG. 2 Mixing of Processed Microphone Channels with Input to Form Output Signals
FIG. 3 AMX External 13.5Vdc Power Supply

Hardware Description
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Alero 8-Channel Microphone Mixer Instruction Manual
Hardware Description
Alero has a metallic enclosure with visual user interfaces located on the front panel and connectivity interfaces on the rear panel.
Front Panel
The Alero front panel is the only side that should be visible in a typical setup. Here, the user can monitor the most essential
statuses in three groups of LEDs as shown in FIG. 4.
The table below provides descriptions of the front panel LEDs used to determine the state of the unit and operation of the
microphones.
Rear Panel
The rear panel is intended to be used by a system installer. FIG. 5 shows all connector inputs and output audio channels as well as
USB, network, and power supply. Also displayed are the factory reset button and a mute control connector.
The following table provides a brief description of the rear panel components with a visual shown in FIG. 6.
FIG. 4 Front Panel LEDs.
Group Description Usage
1 POWER One continuously lit green LED Indicates that the unit is powered on.
2 MICROPHONES – SIGNAL A continuously lit green LED will flicker indicating an active signal on the
corresponding eight microphone channels.
3 MICROPHONES – CLIP Eight red LEDs indicate risk of amplitude clipping on corresponding channel due
to a strong signal. LED is only active for a short time after a strong signal is
detected. Reduce gain on the channel if LED is active.
FIG. 5 Rear Panel Connectors
ID # Connector Title Description
1 5-pin Phoenix VC Video Conference audio channel input and output. Line level
2 3-pin Phoenix LINE IN 2 analog line level inputs
3 3-pin Phoenix LINE OUT 2 analog line level outputs
Continued 
4 5-pin Phoenix PA OUT 2 mono line level outputs for connection to local sound reinforcement (PA)
system.
5 3-pin Phoenix MICROPHONES 8 microphone inputs. Phantom power configurable.
6 6-pin Phoenix MUTE Muting of certain microphone groups by applying contact closure or mic
switch. Up to 5 mute groups may be created. Refer to Active Mute Groups on
page 14 for more details.
7 1 Push Button RESET Reset to factory settings by pressing button while powering on unit, also
used to Switch between static IP and DHCP

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Alero 8-Channel Microphone Mixer Instruction Manual
Hardware Description
Connector Def initions
This section defines the pin outs of the different connector types on the Alero rear panel.
VC - Video Conferencing
The 5-pin 3.5mm Phoenix VC connection is used to connect video conferencing systems to Alero. The line level audio stream may
be fed into the VC input to be broadcast over room speakers amplified by another piece of equipment, like AMX’s DVX, that is
connected to the Alero PA line level output. Alero’s VC output connector provides a clean audio signal to the conferencing unit from
the local meeting room to be broadcast to the remote meeting space.
Line In/Line Out
The 3.5 mm 3-pin captive-wire Phoenix connectors (FIG. 8) marked Line In and Line Out provide left and right channel analog line
levels for inputs and outputs. This interface can be used for a separate audio conference device with POTS dialing capabilities or
used as a record and playback interface.
PA Speaker Output
The 5-pin 3.5mm Phoenix speaker connection (PA) provides a room line level left and right channel outputs to connect to an
amplifier or amplified device. This could go to an Enova DVX All-In-One Presentation Switcher which would then control the volume
to conference room speakers.
8 USB Standard-b USB Audio input/output to connect to a local PC.
9 RJ45 Connector LAN 10/100 Configuration of unit via network. The port has L/A (Link Activity) and SPD
(Speed) LEDs. The L/A flashes indicating traffic, otherwise is constantly lit.
The SPD LED indicates a network link. This LED is off by default, and lights
up when a network link is established.
10 2 pin Phoenix INPUT PWR 12 VDC power supply
FIG. 6 Alero Connection Example
FIG. 7 VC Connector Pin-out
FIG. 8 Line In/Line Out Pin-out
ID # Connector Title Description

Hardware Description
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Alero 8-Channel Microphone Mixer Instruction Manual
Microphone Inputs
The eight 3.5 mm 3-pin captive-wire microphone input connectors (FIG. 10) provide the following features:
Support up to eight mono microphones
Supports Balanced and Unbalanced audio
Microphone Input Level: +20 dBu (maximum)
0 dBu (nominal)
Microphone Input Impedance: Line Input: 50 kΩ
Microphone: 10 kΩ
Microphone Input Gain: -72 - 104 dB
Phantom Power: 48 volt all inputs
Mute Group
Alero provides users the ability to set the eight microphones into five mute groups. These five groups are muted using an external
contact closure. The contacts, connected through the 5-pin 3.5mm Phoenix connector labeled MUTE (FIG. 11), provide a
connection to ground to mute the microphone inputs assigned to the corresponding group through the web interface.
USB Port
The USB port provides a serial bus using a Standard-B connection on the Alero. It can be used to provide audio signals to and from
a PC in certain conference room applications.
The USB Pin-out:
FIG. 9 PA Speaker Connector Pin-ou t
FIG. 10 Microphone Input Pin-out
FIG. 11 Mute Group Input Connector
FIG. 12 USB Port Pin-out
Pin Name Cable Color Description
1VCCRed +5VDC
2D- White Data-
3 D+ Green Data +
4 GND Black Ground

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Alero 8-Channel Microphone Mixer Instruction Manual
Hardware Description
RJ-45 Connector
The 8-pin female 10/100 Port RJ-45 connector provides the following features:
TCP/IP communications
Supports HTTP
Link/Activity LED (green) blinks when receiving Ethernet data packets (on RJ-45 connector and front panel)
Speed Indicator Speed LED (yellow) lights On when the connection speed is 100 Mbps Ethernet connection and turns OFF
when the speed is 10 Mbps
The following diagram shows the pin connections for the RS-232 (RJ-45) port connector.
Power Connector
The power connector is a 3.5mm Phoenix connector with retaining screws to hold the connector secure to the Alero unit FIG. 14.
Alero requires 12 Vdc.
FIG. 13 RJ-45 Receptacle Pin-out
FIG. 14 Power Input Connector

Installation
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Alero 8-Channel Microphone Mixer Instruction Manual
Installation
List of Supplies
The following are items needed to install and turn-up the Alero AEC:
Small Flat-head screwdriver
Wire cutters
Wire strippers
USB A-connector to USB B-connector cable
Cat-5 Ethernet cable
Microphones and cables (balanced or unbalanced okay)
Power supply (PSN 4.4) Refer to Power Supply on page 5.
Power cable
Placement
Determine the best mounting location for your installation. Ensure all cables run between the equipment are not a tripping hazard.
Make a quick diagram of your conference room equipment to try and visualize where the Alero will fit in. FIG. 15 shows what a
typical AMX equipped conference room might look like with Alero placed between a DVX and the Conference equipment.
Connections
Make connections to Alero as needed following these guidelines.
Connect to the Network
1. Connect Alero to the network using an Ethernet cable plugged into the LAN 10/100 port. This port is used for remote device
configuration using the Web interface.
FIG. 15 Alero in an AMX Equipped Conference Room - Example
FIG. 16 Network Connection

Installation
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Alero 8-Channel Microphone Mixer Instruction Manual
Connect Power
1. Connect the power supply using the male two-pin Phoenix screw down plug. Refer to Power Supply on page 5 for details on
the power supply.
2. Secure the plug terminals to the receptacle on the Alero backplate.
3. Plug the power supply into the wall outlet using the cord included with the power supply. Alero will power on automatically.
Connect Audio Conference Equipment
Prepare wire ends by cutting 1/4" of the insulation off of the end of the wires. Insert the stripped ends into the Phoenix style secure
screw terminals (FIG. 18). Refer to the wire guide on the Alero rear panel for each connector type.
+ = Positive
G = Ground
- = Neutral
1. If using an audio conference device, connect the input and output channels to the Alero rear panel Line In and Line Out.
2. The Alero USB port is used to pass audio to local equipment used to make conference calls (i.e., a local room PC being used to
make Skype calls). If using the USB port for Audio output, connect the cable to the USB port (FIG. 19).
Connect Video Conference Equipment
1. If using a video conference device, connect the audio inputs/outputs to the Alero VC connection IN/OUT while passing the
Video signal to the Enova DVX All-In-One Presentation Switcher or other switching equipment. The audio signal will then pass
to the conference room switcher (i.e., DVX) for volume control.
FIG. 17 12-Volt Power Connection
FIG. 18 Audio Conference Device Connections
FIG. 19 Serial Audio Conference Device Connections
FIG. 20 Video Conference Device Connections
Insert
Stripped
Wire Ends
Screw down
terminals Back Panel Wire Guide
Insert Phoenix
style male
connector into
back panel
connections

Installation
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Alero 8-Channel Microphone Mixer Instruction Manual
Microphone Connections
1. Connect up to eight microphones to the rear panel using the Phoenix screw terminal connectors (FIG. 21). "
NOTE: Connect the unbalanced connectors to + (positive) and G (Ground). It is also possible to connect to - (Neutral) and Ground,
but care must be taken so that all microphones and inputs use the same method.
Detect IP address
1. The factory default IP address is set to 192.168.1.2. If DHCP is preferred press the reset button for more than 1 second to
enable it.
2. Locate all devices on network using Zero-conf iguration networking (zeroconf). If there are more than one devices in the list,
determine the IP of the current unit by powering it off and observing which device disappears from the zeroconf utility.
Conf igure Microphone Inputs
1. Select 48 VDC phantom power on/off for each microphone. Refer to Microphone Settings on page 15.
2. Adjust gain settings for individual microphones. Approximately balance the signal levels for all microphone channels in a
typical setup.
3. Configure signal processing on each microphone channel. Refer to Microphone Volume on page 11.
Conf igure Input/Output Channels.
1. Monitor signal amplitude on input channels and adjust gain if necessary. Refer to Levels on page 11.
2. Route analog/digital input channels to each desired output in the signal mixer. Refer to Signal Mixing on page 12. By default
almost all input channels are sent to all output channels with these exceptions:
USBin is not routed to USBout
VCin is not routed to VCout.
3. Monitor signal amplitude on output channels and adjust gain if necessary.
4. Installation complete.
FIG. 21 Microphone Connection Wiring
Balanced Mic Unbalanced Mic

Configuration
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Alero 8-Channel Microphone Mixer Instruction Manual
Conf iguration
When Alero is in operation, the user may change system configuration settings using a web based interface. To access the
configuration pages, open a web browser and enter the IP address for the device.
ex. http://192.168.12.34
Default login credentials are:
Username: admin
Password: admin
The configuration page is designed with a dashboard where the most relevant settings can be adjusted. There are five
configuration pages:
Network Configuration on page 10
Levels on page 11
Signal Mixing on page 12
Microphone Settings on page 15
Basic Configuration on page 16
Network Conf iguration
The default Alero IP and other network settings can be configured on the Network Configuration page (FIG. 22). On this page users
may also enable DHCP to have an IP address assigned by the network automatically.
NOTE: If the manual settings are bad, the device will not be accessible via a configuration page since the network connection will not
work. If this happens, follow the procedure Factory Reset on page 16.
Reset Button
In powered on state, Alero’s factory reset button can be used to reset the IP settings to factory defaults to recover from some
misconfiguration, or to easily enable DHCP to switch to new network.
Short press (< 1 second): Reset to default static IP settings.
Long press (> 1 second): Enable DHCP.
Address Type Conf igured Address
IP Address 192.168.1.2
Gateway 192.168.1.1
Netmask 255.255.255.0
FIG. 22 Network Configuration Page

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Alero 8-Channel Microphone Mixer Instruction Manual
Configuration
Levels
To get an overview of current audio signal levels for all input and output channels, open the Levels page (FIG. 23). This page has
three sections further defined below:
Signal Level
Microphone Volume
Channel Volume
Signal Levels
The Signal Level chart is a real time indication of the microphone input channels and Alero’s output channel activity and volume
levels.
Amplitude Limiters
Alero provides limiting which prevents each output from exceeding a predetermined level. The auto limiting feature will very quickly
prevent the signal from clipping. Indicators are provided for each output that display when the signal has reached the limiting
threshold by filling in the circle.
Microphone Volume
In audio mixers there is generally a two stage volume control. Stage one (Input Gain) compensates for the wide range of levels
that may be presented by the various types of microphones with diverse gain structures. Stage two provides a compensated volume
range (Volume Level) that is used to adjust the levels in a nominal range.
Input Gain
The Input Gain adjustment is the first stage and sets the input mic gain. With the Volume Level set to 0 db, set the Input Gain mic
level as high as possible without any audible distortion, with some margin (approximately around 35 dB).
FIG. 23 Levels Page - Signal Levels Chart
FIG. 24 Levels Page - Signal Levels Chart

Configuration
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Alero 8-Channel Microphone Mixer Instruction Manual
Volume Level
The Volume Level adjustment controls the nominal level and provides for uniform level adjustments in real time. If the analog level
is driven to distortion, no adjustment of the this level will compensate for this distortion. If the Input Gain level is too low, the
Volume Level will not be able to raise it enough to compensate.
The AGC (Automatic Gain Control) works in the Volume Level and attempts to regulate the volume output based on the mic input
receiving the strongest signal.
Channel Volume
The Channel Volume section also enables users to adjust Input Gain and Volume Level on each of the Alero Input and Output
channels. Set each channel as needed.
Signal Mixing
The Signal Mixing page enables users to specify which inputs to Alero are connected to specific outputs, which microphones are in
a mute group, and monitor mic activity and levels.
Signal Levels
The Signal Level chart is a real time reflection of the microphone input channels and Alero output channels activity and volume
levels.
FIG. 25 Levels Page - Signal Levels Chart
FIG. 26 Signal Levels

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Alero 8-Channel Microphone Mixer Instruction Manual
Configuration
Selection of Mixing Microphones (AMM)
The Automatic Microphone Mixing (AMM) module selects microphones to be active based on the input signal level detected on each
microphone. To remove certain microphones from the selection so they will never be used, click on the microphone column for the
desired output channel. This will turn the square white indicating that it is no longer selected.
NOTE: The AMM detects if a microphone is not connected so there is no need to remove unconnected microphones from the AMM
selection.
It is possible to configure input to output channel routing and AMM settings using the chart in FIG. 27. To disable a certain
microphone from an output channel, deselect the square in the mic column that corresponds to the output channel row. The blue
square will turn white once it has been disabled.
Active microphones are displayed by an "ACTIVE" indicator (FIG. 27). It is possible to disable AMM for individual output channels by
pressing the gray AMM symbol under the output channel shown in the chart below. This causes all the AMM symbol to turn white
and the microphone signals in that row to be consistently in an ACTIVE state and added to that output channel.
Signal Mixing
The Signal Mixing chart (FIG. 28) shows the default input to output channel mixing settings. All input channels are routed to all
output channels except the following:
the USB Input is not routed to the USB Output
the VC Input is not routed to the VC Output
To remove an input channel from an output channel, click on the corresponding row/column to turn the square white.
FIG. 27 AMM Settings and Mic Input to Output Channel Signal Routing.
FIG. 28 Input to Output Signal Routing.

Configuration
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Alero 8-Channel Microphone Mixer Instruction Manual
Active Mute Groups
The Microphone mute groups are shown at the bottom of the Signal Mixing page. The microphones can be placed in five different
mute-groups. Each of these groups may be muted by setting the corresponding pin of connection 6 shown in the table on page 4
to ground. An indicator shows the state of each of the five mute groups; muted (active) / unmuted (not active), as well as a
selection matrix for assigning microphones to the different groups. Note that one microphone can be placed into several groups.
The microphone is muted as long as any mute group it is assigned to is active (muted).
FIG. 29 Configuration of Mute Groups.

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Alero 8-Channel Microphone Mixer Instruction Manual
Configuration
Microphone Settings
It is possible to configure the signal processing modules that operate on the microphone signals from the Microphone Settings
page (FIG. 30). It is also possible to enable 48 VDC phantom power to microphones from this page.
Signal processing configuration options are defined below.
FIG. 30 Configuration of Signal Processing Applied to Microphone Signals.
Signal processing Options Default Description
Acoustic Echo Cancellation On/Off On Removes recognized echo by subtracting it from the
transmitted or received signal.
Comfort Noise Generation On/Off On Introduces a synthetic background noise to fill the
artificial transmission silence resulting from voice
activity detection.
Residual Echo Suppression On/Off On Inserts loss to prevent a speaker from hearing his own
voice.
Light/Medium/Strong Medium
Noise Reduction On/Off On Reduces noise as it occurs for live broadcast
applications.
0 dB to 24 dB 12 dB