This symbol is intended to alert the user of important operating and
maintenance (servicing) instructions in the literature provided with the
equipment.
This symbol is intended to alert the user of the presence of uninsulated
dangerous voltage within the product enclosure that may present a risk of
electric shock.
Caution
Read Instructions • Read and understand all safety and operating instructions before using the equipment.
Retain Instructions • The safety instructions should be kept for future reference.
Follow Warnings • Follow all warnings and instructions marked on the equipment or in the user information.
Avoid Attachments • Do not use tools or attachments that are not recommended by the equipment
manufacturer because they may be hazardous.
Warning
Power sources • This equipment should be operated only from the power source indicated on the product. This
equipment is intended to be used with a main power system with a grounded (neutral) conductor. The third
(grounding) pin is a safety feature, do not attempt to bypass or disable it.
Power disconnection • To remove power from the equipment safely, remove all power cords from the rear of the
equipment, or the desktop power module (if detachable), or from the power source receptacle (wall plug).
Power cord protection • Power cords should be routed so that they are not likely to be stepped on or pinched by
items placed upon or against them.
Servicing • Refer all servicing to qualified service personnel. There are no user-serviceable parts inside. To prevent
the risk of shock, do not attempt to service this equipment yourself because opening or removing covers may
expose you to dangerous voltage or other hazards.
Slots and openings • If the equipment has slots or holes in the enclosure, these are provided to prevent
overheating of sensitive components inside. These openings must never be blocked by other objects.
Lithium battery • There is a danger of explosion if battery is incorrectly replaced. Replace it only with the same or
equivalent type recommended by the manufacturer. Dispose of used batteries according to the instructions of
the manufacturer.
Consignes de Sécurité • Français
Ce symbole sert à avertir l’utilisateur que la documentation fournie avec le
matériel contient des instructions importantes concernant l’exploitation et la
maintenance (réparation).
Ce symbole sert à avertir l’utilisateur de la présence dans le boîtier
de l’appareil de tensions dangereuses non isolées posant des risques
d’électrocution.
Attention
Lire les instructions• Prendre connaissance de toutes les consignes de sécurité et d’exploitation avant d’utiliser
le matériel.
Conserver les instructions• Ranger les consignes de sécurité afin de pouvoir les consulter à l’avenir.
Respecter les avertissements • Observer tous les avertissements et consignes marqués sur le matériel ou
présentés dans la documentation utilisateur.
Eviter les pièces de fixation • Ne pas utiliser de pièces de fixation ni d’outils non recommandés par le fabricant
du matériel car cela risquerait de poser certains dangers.
Sicherheitsanleitungen • Deutsch
Dieses Symbol soll dem Benutzer in der im Lieferumfang enthaltenen
Dokumentation besonders wichtige Hinweise zur Bedienung und Wartung
(Instandhaltung) geben.
Dieses Symbol soll den Benutzer darauf aufmerksam machen, daß im Inneren
des Gehäuses dieses Produktes gefährliche Spannungen, die nicht isoliert sind
und die einen elektrischen Schock verursachen können, herrschen.
Achtung
Lesen der Anleitungen • Bevor Sie das Gerät zum ersten Mal verwenden, sollten Sie alle Sicherheits-und
Bedienungsanleitungen genau durchlesen und verstehen.
Aufbewahren der Anleitungen • Die Hinweise zur elektrischen Sicherheit des Produktes sollten Sie
aufbewahren, damit Sie im Bedarfsfall darauf zurückgreifen können.
Befolgen der Warnhinweise • Befolgen Sie alle Warnhinweise und Anleitungen auf dem Gerät oder in der
Benutzerdokumentation.
Keine Zusatzgeräte • Verwenden Sie keine Werkzeuge oder Zusatzgeräte, die nicht ausdrücklich vom Hersteller
empfohlen wurden, da diese eine Gefahrenquelle darstellen können.
Avertissement
Alimentations • Ne faire fonctionner ce matériel qu’avec la source d’alimentation indiquée sur l’appareil. Ce
matériel doit être utilisé avec une alimentation principale comportant un fil de terre (neutre). Le troisième
contact (de mise à la terre) constitue un dispositif de sécurité : n’essayez pas de la contourner ni de la
désactiver.
Déconnexion de l’alimentation• Pour mettre le matériel hors tension sans danger, déconnectez tous les cordons
d’alimentation de l’arrière de l’appareil ou du module d’alimentation de bureau (s’il est amovible) ou encore de
la prise secteur.
Protection du cordon d’alimentation • Acheminer les cordons d’alimentation de manière à ce que personne ne
risque de marcher dessus et à ce qu’ils ne soient pas écrasés ou pincés par des objets.
Réparation-maintenance • Faire exécuter toutes les interventions de réparation-maintenance par un technicien
qualifié. Aucun des éléments internes ne peut être réparé par l’utilisateur. Afin d’éviter tout danger
d’électrocution, l’utilisateur ne doit pas essayer de procéder lui-même à ces opérations car l’ouverture ou le
retrait des couvercles risquent de l’exposer à de hautes tensions et autres dangers.
Fentes et orifices • Si le boîtier de l’appareil comporte des fentes ou des orifices, ceux-ci servent à empêcher les
composants internes sensibles de surchauffer. Ces ouvertures ne doivent jamais être bloquées par des objets.
Lithium Batterie • Il a danger d’explosion s’il y a remplacment incorrect de la batterie. Remplacer uniquement
avec une batterie du meme type ou d’un type equivalent recommande par le constructeur. Mettre au reut les
batteries usagees conformement aux instructions du fabricant.
Vorsicht
Stromquellen • Dieses Gerät sollte nur über die auf dem Produkt angegebene Stromquelle betrieben werden.
Dieses Gerät wurde für eine Verwendung mit einer Hauptstromleitung mit einem geerdeten (neutralen) Leiter
konzipiert. Der dritte Kontakt ist für einen Erdanschluß, und stellt eine Sicherheitsfunktion dar. Diese sollte nicht
umgangen oder außer Betrieb gesetzt werden.
Stromunterbrechung • Um das Gerät auf sichere Weise vom Netz zu trennen, sollten Sie alle Netzkabel aus der
Rückseite des Gerätes, aus der externen Stomversorgung (falls dies möglich ist) oder aus der Wandsteckdose
ziehen.
Schutz des Netzkabels • Netzkabel sollten stets so verlegt werden, daß sie nicht im Weg liegen und niemand
darauf treten kann oder Objekte darauf- oder unmittelbar dagegengestellt werden können.
Wartung • Alle Wartungsmaßnahmen sollten nur von qualiziertem Servicepersonal durchgeführt werden. Die
internen Komponenten des Gerätes sind wartungsfrei. Zur Vermeidung eines elektrischen Schocks versuchen
Sie in keinem Fall, dieses Gerät selbst öffnen, da beim Entfernen der Abdeckungen die Gefahr eines
elektrischen Schlags und/oder andere Gefahren bestehen.
Schlitze und Öffnungen • Wenn das Gerät Schlitze oder Löcher im Gehäuse aufweist, dienen diese zur
Vermeidung einer Überhitzung der empndlichen Teile im Inneren. Diese Öffnungen dürfen niemals von
anderen Objekten blockiert werden.
Litium-Batterie • Explosionsgefahr, falls die Batterie nicht richtig ersetzt wird. Ersetzen Sie verbrauchte Batterien nur
durch den gleichen oder einen vergleichbaren Batterietyp, der auch vom Hersteller empfohlen wird. Entsorgen
Sie verbrauchte Batterien bitte gemäß den Herstelleranweisungen.
Instrucciones de seguridad • Español
Este símbolo se utiliza para advertir al usuario sobre instrucciones
importantes de operación y mantenimiento (o cambio de partes) que se
desean destacar en el contenido de la documentación suministrada con los
equipos.
Este símbolo se utiliza para advertir al usuario sobre la presencia de
elementos con voltaje peligroso sin protección aislante, que puedan
encontrarse dentro de la caja o alojamiento del producto, y que puedan
representar riesgo de electrocución.
Precaucion
Leer las instrucciones • Leer y analizar todas las instrucciones de operación y seguridad, antes de usar el
equipo.
Conservar las instrucciones • Conservar las instrucciones de seguridad para futura consulta.
Obedecer las advertencias • Todas las advertencias e instrucciones marcadas en el equipo o en la
documentación del usuario, deben ser obedecidas.
Evitar el uso de accesorios • No usar herramientas o accesorios que no sean especificamente recomendados
por el fabricante, ya que podrian implicar riesgos.
Alimentación eléctrica • Este equipo debe conectarse únicamente a la fuente/tipo de alimentación eléctrica
indicada en el mismo. La alimentación eléctrica de este equipo debe provenir de un sistema de distribución
general con conductor neutro a tierra. La tercera pata (puesta a tierra) es una medida de seguridad, no
puentearia ni eliminaria.
Desconexión de alimentación eléctrica • Para desconectar con seguridad la acometida de alimentación eléctrica
al equipo, desenchufar todos los cables de alimentación en el panel trasero del equipo, o desenchufar el
módulo de alimentación (si fuera independiente), o desenchufar el cable del receptáculo de la pared.
Protección del cables de alimentación • Los cables de alimentación eléctrica se deben instalar en lugares donde
no sean pisados ni apretados por objetos que se puedan apoyar sobre ellos.
Reparaciones/mantenimiento • Solicitar siempre los servicios técnicos de personal calicado. En el interior no
hay partes a las que el usuario deba acceder. Para evitar riesgo de electrocución, no intentar personalmente la
reparación/mantenimiento de este equipo, ya que al abrir o extraer las tapas puede quedar expuesto a voltajes
peligrosos u otros riesgos.
Ranuras y aberturas • Si el equipo posee ranuras o orificios en su caja/alojamiento, es para evitar el
sobrecalientamiento de componentes internos sensibles. Estas aberturas nunca se deben obstruir con otros
objetos.
Batería de litio • Existe riesgo de explosión si esta batería se coloca en la posición incorrecta. Cambiar esta batería
únicamente con el mismo tipo (o su equivalente) recomendado por el fabricante. Desachar las baterías usadas
This equipment has been tested and found to comply with the limits for a Class A digital
device, pursuant to part 15 of the FCC rules. The Class A limits 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 not installed and used in accordance with the instruction manual, may cause harmful
interference to radio communications. Operation of this equipment in a residential area is
likely to cause interference; the user must correct the interference at his own expense.
NOTE: This unit was tested with shielded I/O cables on the peripheral devices. Shielded
cables must be used to ensure compliance with FCC emissions limits.
For more information on safety guidelines, regulatory compliances,
EMI/EMF compatibility, accessibility, and related topics, see the “Extron Safety
and Regulatory Compliance Guide” on the Extron website.
Conventions Used in this Guide
Notications
ATTENTION: Attention indicates a situation that may damage or destroy the product
or associated equipment.
NOTE: A note draws attention to important information.
TIP: A tip provides a suggestion to make working with the application easier.
This user guide contains information about the Extron MLA VC10 Plus volume control
module with instructions for experienced installers on how to install, configure, and
operate the equipment.
Unless otherwise specied, references in this guide to the “MLA” relate to the features or
operation of the MLA VC10 Plus.
References to the “control processor” or “controller” refer to the Extron or third-party
controller that provides RS-232 commands to the MLA VC10 Plus.
References to “amplier” relate to any amplier and mixer under the control of the MLA.
MLA VC10 Plus Description
The MLA VC10 Plus is a MediaLink® accessory volume control module. It converts RS-232
commands from a control system into voltage or impedance changes to control audio
ampliers with volume and mute control ports. It can be used with Extron or third-party
controllers and audio amplifiers that have remote volume control capability.
The MLA VC10 Plus is compatible with the following control devices:
zExtron MediaLink controllerszExtron IP Link
zThird party control systems capable of RS-232 serial control
®
control processors
The MLA VC10 Plus is compatible with Extron ampliers, including:
zMPA 152 and MPA 401
zXPA 1002 and XPA 2001
zMP 101
MLA VC10 Plus Features
Volume and mute control — The MLA VC10 provides volume and mute control for the
Extron MPA or XPA half-rack series ampliers and many third-party ampliers.
High resolution volume control range — Provides smooth volume changes without
audible level jumps.
Compatible with multiple control systems — The volume control module uses an
RS-232 protocol that is compatible with Extron and third-party serial-capable controllers.
Adjustable maximum limit on variable voltage or resistance control — The
amplier volume level is adjusted using voltage (0 - 10 VDC) or resistance (0 - 10 kilohm
potentiometer) control. The maximum control voltage or resistance range can be reduced
to avoid damage to third party amplifiers that need a lower control range or to limit the
maximum audio output of the amplifier.
Linear or logarithmic taper modes — These modes are available for both voltage and
resistance control and provide a choice between consistent linear or natural logarithmic
volume changes.
MLA VC10 Plus • Introduction1
Inverse mode — In normal mode, 0 is mute and 10 VDC or 10 kilohm is the maximum
volume. In inverse mode, this reverses the output to 0 (maximum volume) to 10 VDC or
10 kilohm (minimum volume).
Relay switch — This switch has a Normally Open (NO) pin and a Normally Closed (NC)
pin. This relay can be used to mute audio on an amplifier or mixer.
Auto Mute — When the volume level is at 0, this feature allows the MLA VC10 Plus to
trigger this relay to mute the amplifier, via mute contact closure terminals on the amplifier.
By default this feature is enabled.
Soft Start — The audio level is gently ramped to restore volume to its previous level after
a mute or a power cycle to prevent loud bursts of sound and to protect the amplifier and
speakers from possible damage.
Isolation — Isolated digital circuitry prevents noise in the signal path. All control ports are
isolated from each other to eliminate induced noise.
RS-232 serial control — The MLA VC10 Plus can be controlled by Extron Simple
Instruction Set (SIS™) commands either via the controller or directly from a PC using the
front panel USB port or the rear panel 3-pole captive screw connector.
Optional ENERGY STAR® qualified power supply — This external universal power
supply (PS 1210 C, part number 70-775-01) provides worldwide compatibility, low power
consumption, and reduced operating costs.
RELAY
Extron
CONTROL
OUTPUT
REMOTE
RS-232
POWER
12V
0.3A MAX
Tx Rx G GGV C
1
VCR
CONFIG
MLC 104 IP PLUS
2
DVD
3
PC
4
DISPLAY
Extron
MLC 104 IP Plus
MediaLink
Controller
ON
VOLUME
OFF
RS-232
1 2
LIMITER/PROTECT
SIGNAL
OVER
TEMP
MLA VC10 Plus
NO NCC
R
Volume Control Module
V-DC
Variable
Impedance
Output
XPA 1002
Extron
SI 26
Surface-mount
Speakers
Figure 1. MLA VC10 Plus Application Diagram
Extron
XPA 1002
Power
Amplier
MLA VC10 Plus • Introduction2
Panels and
Connections
This section describes the features and connectors for the MLA VC10 Plus:
zFront Panel Connections and Features
zRear Panel Connections
Front Panel Connections and Features
MLA VC10 Plus
a
b
MUTE
RELAY
CONFIG
R
e
d
c
Figure 2. MLA VC10 Plus Front Panel
a Power and Activity LED —
zIs off when the unit is not receiving power
zLights solid green when the unit is receiving power
zContinuously flashes green while SIS commands are received.
b Audio Mute LED — lights solid green when volume level is at 0 or is muted.
c Relay LED —
zLights solid green when the relay is triggered or toggled on.
zPulses when the relay is momentarily triggered
dConfig port — A USB cable can be connected to this mini B USB female port when
using a PC to connect to the MLA VC10 Plus.
NOTE: During configuration, the host PC provides power through the USB cable.
This is sufficient to power the unit during configuration only. For normal
use, the unit must receive power from a 12 VDC power supply.
e Reset Button — used to reset to the factory-installed firmware (see page 19).
MLA VC10 Plus • Panels and Connections3
Rear Panel Connections
fgjih
CONTROL
OUTPUT
POWER
REMOTE
12V
0.3A MAX
RS-232
Tx Rx GG GVC
V-DC
RELAY
NONCC
R
Figure 3. MLA VC10 Plus Rear Panel
fPower — Connect a 12 VDC power supply to this two pole captive screw connector.
The MLA VC10 Plus can be wired to share the power supply with other products
(see “Sharing a Power Supply with an Extron Controller” page 12 for more
information). The Extron power supply (part number 70-775-01) is optional.
ATTENTION: Before connecting power, see “Connections to a Power Supply”
on page 11 for important information about using the power
supply.
g RS-232 control — The MLA VC10 Plus is controlled by RS-232 instructions from
a MediaLink, IP Link, or third-party controller or a PC. Connect the RS-232 control
cables, from the controller or PC to this 3.5 mm, 3-pole captive screw connector.
hV-DC control — To use variable DC voltage output to control the volume of an
amplier, connect the MLA VC10 Plus to the amplier using this 3.5 mm, 2-pole
captive screw connector.
NOTES: The amplifier audio level can be controlled by either voltage or by
resistance but, at any time, only one can be active, see “Modes” in the
SIS commands on page 35.
i Resistance Control (default setting) — To use the digital potentiometer to control
an amplier, connect the MLA VC10 Plus to the amplier using this 3.5 mm, 3-pole
captive screw connector.
j Relay Switch — To use the relay for mute control or other purposes, determine
whether the amplifier needs a Normally Closed (NC) or Normally Open (NO) relay.
Connect the common (C) pole and either the NO or the NC pole of the captive screw
connector to the amplifier.
MLA VC10 Plus • Panels and Connections4
Installation
and Cabling
This section describes
zInstallation Overview
zConnections for Volume Control
zConnections to a Power Supply
zRS-232 Connections
zRelay
Installation Overview
This section provides a brief overview of how to install and set up the MLA VC10 Plus.
1. Decide where the MLA VC10 Plus will be placed and, if necessary, any mounting
requirements (see page 37).
NOTE: To avoid picking up background noise in the cable, use shielded cable
(for example Extron STP 22 cable) and place the MLA VC10 Plus as close
as possible to the amplifier. Extron recommends that the maximum cable
length between the MLA VC10 Plus and the amplifier should be six feet.
2. Read the user guide for the amplifier or mixer. Determine the remote volume control
requirements of the unit.
Potentiometer mode (default) — connect the potentiometer terminals on the
MLA VC10 Plus to the amplifier (see pages 6 and 7).
NOTE: The majority of amplifiers researched and tested by Extron work with the
MLA VC10 Plus straight from the box, using 10 kilohm resistance control,
without further configuration.
Voltage mode — The unit needs configuration, using SIS commands. Determine the
control voltage of the amplifier (see ”Volume Control by Variable DC Voltage,” on
page 8) and connect the voltage terminals on the MLA VC10 Plus to the amplifier
(see page 9).
If necessary, connect a PC to the front panel USB port and configure the
MLA VC10 Plus using SIS commands.
3. After conguring the unit, disconnect the front panel USB connection.
4. Connect the three RS-232 terminals of the MLA VC10 Plus to an Extron control
processor (see page 13) or a third party control device (see page 14).
5. To use the relay control, connect the relay terminals of the MLA VC10 Plus to the
amplifier (see page 15).
MLA VC10 Plus • Installation and Cabling5
6. Connect a power supply (see page 11).
Extron
ATTENTION: Read the attention points on page 11 before connecting the
power supply.
If the MLA VC10 Plus is being used with Extron MLC or IP Link control processors, the
units can share a power supply (see the wiring diagram shown on page 12). If the
volume control module is used with any other control device, it requires a separate
12 VDC power supply. Extron provides a 12 VDC, 1 A power supply (part number
70-775-01), which must be purchased separately.
Connections for Volume Control
The MLA VC10 Plus controls the remote volume control port of an amplier. All Extron
MPA and half-rack XPA amplifiers and most third-party models can be controlled by a
potentiometer, which is the default setting for the MLA VC10 Plus. Other third-party
amplifiers may require a variable DC voltage signal to control the audio volume.
Consult the user guide for the amplifier to find out the specific requirements of your
equipment before connecting it to the MLA VC10 Plus. Additionally, the audio can be
muted by connecting the captive screw relay connections to the contact closure mute
terminals of the amplifier, if they are available.
Volume Control by Potentiometer
The following examples show how to wire the resistance control terminals of the
MLA VC10 Plus to the Extron MPA and half-rack XPA ampliers, or some common
third-party amplifiers.
When using three-pin potentiometer control, RS-232 commands control the variable
resistance across the signal (wiper) pin (C) to the ground pin (G). Across the reference (V)
and ground (G) will always be xed at 10 kilohm. Other controllers and ampliers not
shown here require similar connections, but you must read the appropriate user guides to
ensure the wiring is correct.
Extron Amplier
This example shows how to connect the MLA VC10 Plus to an Extron amplier. All Extron
amplifiers can be controlled by a potentiometer, using three pins.
NOTES:• By default, the MLA VC10 Plus control mode is set to potentiomenter and
the maximum resistance output range is set to 10 kilohm. These are the
settings required by all Extron amplifiers.
• Volume control pins may be labeled as V, C, and G (see the half-rack
XPA Series Amplifier) or 10V, Vol/Mute, and G (see the MPA Amplifier). The
wiring and function are the same, whichever way your product is labeled.
1. If necessary, use SIS commands to set
the control mode (see page 35) to
potentiometer and set the maximum
potentiometer output range (see
page 35).
Extron
MLA VC10 Plus
R
GVC
Extron MPA
Amplifier
10V50mA
VOL/MUTE
REMOTE
OR
Half-rack
XPA Series
Amplifier
10V 50mA
GVC
G
STANDBY
2. Connect the reference voltage pin (V) from
the MLA VC10 Plus to the reference voltage
terminal (10V on the MPA; V on the XPA).
Ground
G
Control (variable)
C
Reference
V
MLA VC10 Plus • Installation and Cabling6
G
C
V
3. Connect the ground pin (G) from the MLA VC10 Plus to the ground terminal ( on the
MPA; G on the XPA).
4. Connect the signal (wiper) pin (C) from the MLA VC10 Plus to the signal terminal
(VOL/MUTE on the MPA; C on the XPA).
Third-party amplier (three terminals)
ATTENTION: For third-party amplifiers, consult the user guide for the amplifier to see
how the manufacturer has labeled the different connectors and whether
two or three terminals are used for potentiometer control.
This example shows the MLA VC10 Plus connected
to an Ashly NE series amplier, which requires
a maximum potentiometer output range of
10 kilohms.
Extron MLA VC10 Plus
R
GVC
Ashly NE series
CH 4
CH 3
CH 2
GND
+5V
CH 1
1. Connect the reference voltage pin (V) from
the MLA VC10 Plus to the reference voltage
terminal (+5V) on the amplier.
2. Connect the ground wire (G) from the
MLA VC10 Plus to the ground terminal ( ) on
the amplifier.
G
Ground
Control (variable)
C
Reference
V
3. Connect the signal (wiper) wire (C) from the
MLA VC10 Plus to the signal terminal (CH 1)
on the amplifier.
Third-party amplier (two terminals)
This example shows the MLA VC10 Plus connected
to a TOA 900 Series amplifier, which requires a
potentiometer output range of 10 kilohms.
1. Connect the ground wire (G) from the
MLA VC10 Plus to the left REMT VOL terminal on
the amplifier.
2. Connect both the reference wire (V) and the signal
wire (C) from the MLA VC10 Plus to the right
REMT VOL terminal on the amplier.
This can be achieved by connecting the signal
terminal (C) of the MLA VC10 Plus to both the
right REMT VOL terminal on the amplifier and the
reference terminal (V) of the MLA VC10 Plus.
Extron MLA VC10 Plus
R
TOA 900 Series
GVC
G Ground
Connect the signal (C) and reference (V)
terminals of the MLA VC10 Plus.
Connect the signal (C) terminal to the amplifier.
C Control (variable)
Amplifier
MUTE
GND
2
MUTE
REMT
VOL
1
MLA VC10 Plus • Installation and Cabling7
Volume Control by Variable DC Voltage
When volume is being controlled by variable voltage, serial SIS commands sent from the
controller to the MLA VC10 Plus control the voltage output across the signal (+) and
ground (G) pins. This in turn, controls the audio level of the amplier.
Consult the user guide for the amplifier to find out the specific requirements of your
equipment before connecting it to the MLA VC10 Plus. If the amplier requires variable
DC voltage control, you will need to find out the maximum control voltage, to avoid
damaging the equipment. The user guide for the amplifier may list the required voltage.
The table that starts on page 28 shows the voltage requirements of many common
ampliers. However, Extron recommends that you conrm the voltage yourself by reading
the user guide for the amplifier or, if necessary, using a voltmeter.
This section describes how to measure the control voltage for two widely -used amplifiers.
zPeavey UMA 35T II
zBiamp Precedence CMA 60
NOTE: The MLA VC10 Plus is compatible with a wide range of amplifiers. The models
shown in this section are included as examples only. The MLA VC10 Plus is not
limited to working with only the amplifiers shown in this guide.
After describing how to measure the control voltage, the guide describes how to connect
the MLA VC10 Plus to an amplier for volume control by voltage.
Measuring the Peavey UMA 35T II control voltage
In the example shown below, the voltage control pins are labeled “Remote Vol.” Use a
voltmeter, set to VDC, to measure the voltage. Make a record of the measured voltage and
which terminal is ground. If the voltage is negative the meter probes need to be reversed.
Figure 4. Measuring the Peavey UMA 35T II Control Voltage
MLA VC10 Plus • Installation and Cabling8
Measuring the Biamp Precedence CMA 60 control voltage
Several Biamp ampliers have three screw terminals labeled “remote level.” The terminals,
shown in the inset in figure 5, are reference (+10v), ground ( ), and control voltage (C).
Use a voltmeter to measure the voltage between the control terminal and the ground
terminal as shown in figure 5. Record the measured voltage and which terminal is ground.
Figure 5. Biamp Precedence CMA 60
NOTES:• For three-terminal amplifiers, always connect the MLA VC10 Plus to the
control voltage terminal and ground terminal on the control port of the
amplifier. Leave the other terminal (+10V in this example) unconnected.
• The MLA VC10 Plus provides a variable control voltage (supply voltage) of
0 to 10 VDC. The MLA VC10 Plus can control amplifers that use a higher
control voltage. However, in this situation, the maximum volume may not be
reached.
Connections for volume control by variable DC voltage
This example shows an amplier that requires a maximum output voltage of 10 VDC.
ATTENTION: Be certain you know the maximum control voltage for your amplier.
If the voltage from the MLA VC10 Plus exceeds the maximum control
voltage of the amplifier, the amplifier can be damaged.
1. Connect the USB port of the MLA VC10 Plus (d in the Front Panel diagram on
page 3) to a computer with the Extron DataViewer software installed.
NOTES: • See “Software Installation” on page 18 for information about
downloading and installing DataViewer on your computer.
• Whenever possible, Extron recommends configuring the MLA VC10 Plus,
before connecting the unit to the amplifier.
• For a complete description of SIS commands, see page 31.
2. If necessary, use the following SIS command to set the MLA VC10 Plus control mode
to voltage:
EM*1VLCM}
MLA VC10 Plus • Installation and Cabling9
3. Ensure you know the maximum control voltage for your amplier. In this example, the
Extron
Amplifier
maximum voltage output range for the amplier is 10 VDC.
For more information, see the user guide for the amplifier or measure the voltage, as
described in the previous section.
4. If necessary, use an SIS command to set maximum voltage
output. For example, to set the maximum voltage to 7.5 V:
EV*7.50VLCM}
5. Disconnect the USB connection to the computer.
MLA VC10 Plus
V-DC
G
+10V
GNDVc
6. Connect the MLA VC10 Plus Voltage pins to the amplier:
zConnect the ground (G) terminal of the MLA VC10 Plus to
the ground (GND) terminal of the amplier.
zConnect the control signal voltage (+) terminal of the
MLA VC10 Plus to the control signal voltage (Vc) terminal
G to GND
+ to Vc
of the amplifier.
ATTENTION: There is some variation in how manufacturers mark control
terminals. To ensure that connections between the volume control
module and the amplifier are wired correctly, see the user guide for
that device.
NOTES:• See the notes on page 11 for important information about connecting
wires to captive screw connectors.
• The cable between the MLA VC10 Plus and the amplifier should not be
more than 6 feet (1.8 m). Longer cables can pick up background noise
that affects sound quality.
• In some applications the front panel volume control knob of the
amplifier may be disabled when the MLA VC10 Plus is attached to the
control port of the amplifier. In those cases the volume can only be
controlled by the MLA.
MLA VC10 Plus • Installation and Cabling10
Connections to a Power Supply
Rear Panel
NOTE: During configuration, the host PC provides power through the USB cable.
This is sufficient to power the unit during configuration only. During normal
operation, the unit must receive power from a 12 VDC power supply.
Connect a 12 VDC, power supply to this two pole captive screw connector. Ensure the
connections have the correct polarity (see figure 6).
NOTES:• The length of the exposed wires in the stripping process is critical. The ideal
length is 3/16 inches (5 mm). Any longer and the exposed wires may touch,
causing a short circuit between them. Any shorter and the wires can be
easily pulled out even if tightly fastened by the captive screws.
• Do not tin the wires. Tinned wire does not hold its shape and can become
loose over time.
The MLA VC10 Plus can be wired to share power with an Extron MLC or IP Link control
processor (see page 12). If it is used with a third party control processor, it must be
connected to a separate 12 VDC, power supply. Read the attention points below for
important information about connecting the MLA VC10 Plus to a power supply.
Power Receptacle
POWER
12V
0.3A MAX
Smooth
Ridges
AA
POWER
12V
0.3A MAX
SECTION A–A
DC Power Cord
Captive Screw Connector
+12 VDC
AC Power Cord
Power Supply
Output Cord
External
Power Supply
(12 VDC, 1 A )
(5 mm) Max.
Figure 6. Power Supply Connection
ATTENTION:• Always use a power supply supplied by or specied by Extron. Use
of an unauthorized power supply voids all regulatory compliance
certification and may cause damage to the supply and the end
product.
• Unless otherwise stated, the AC/DC adapters are not suitable for
use in air handling spaces or in wall cavities. The power supply is
to be located within the same vicinity as the Extron AV processing
equipment in an ordinary location, Pollution Degree 2, secured to the
equipment rack within the dedicated closet, podium or desk.
• The installation must always be in accordance with the applicable
provisions of National Electrical Code ANSI/NFPA 70, article 75 and the
Canadian Electrical Code part 1, section 16. The power supply shall
not be permanently fixed to building structure or similar structure.
• Do not use the power supply to power a third party controller jointly
with the MLA VC10 Plus. For the power requirements of the third-
party control system, see the appropriate user guide.
3/16"
MLA VC10 Plus • Installation and Cabling11
Sharing a Power Supply with an Extron Controller
Extron MLA VC10 Plus
The MLA VC10 Plus can share a power supply with any Extron MLC or IP Link control
processor.
NOTES:• Power cables must be at least 18 AWG.
• If the cable has a drain wire, it should be grounded at both ends. To avoid
introducing noise and static into audio channels, the chassis of the control
processor (if used), the power supply, the MLA VC10 Plus, and the amplifier
or mixer should all share a common ground.
• The 12 VDC power supply that ships with the MediaLink or IP Link control
processor can provide power for both the MLA VC10 Plus and the Extron
control processor. It is not included with the MLA VC10 Plus.
To connect the MLA VC10 Plus to the power supply and an Extron control processor
follow these instructions and see figure 7, below.
ATTENTION: Read the attention notice on page 11 for important information
about power supplies.
Check the polarity of the wires from the power supply and connect them to the captive
screw power input on the MLA VC10 Plus rear panel. Connect the same captive screw
sockets to the power input on the MLC or IP Link control processor.
NOTE: See the notes on page 11 for important information about wiring captive
screw connectors.
POWER
12V
0.3A MAX
An External
Power Supply
(12 VDC, 1A max.)
Ground all Devices
+12 VDC (+)
(–)
AB
RS-232 12V
MLC 104 IP Plus
Power Input
Tx
Rx
GROUND
GROUND
MLS PWR
+12V IN
OR
(+) 12 VDC
(–)
POWER
12V
.5A MAX
IPL T SFI244
Power Input
Figure 7. Connecting a Power Supply and Controllers to the MLA VC10 Plus
MLA VC10 Plus • Installation and Cabling12
RS-232 Connections
Extron MLA VC10 Plus
Connections to an Extron Control Processor
Control processors issue SIS commands to the MLA VC10 Plus. For a list of SIS commands,
see the “Command and Response Table for SIS Commands,” starting on page 33.
NOTE: For permanent installations, use the RS-232 port, not the front panel USB port.
Serial drivers for Extron control processors are available for free download from the Extron
website. These drivers are used to configure the control processor quickly and efficiently
so that it will work with the MLA VC10 Plus. See the user guide for your control processor,
which is also available on the Extron website.
Connect the MLA VC10 Plus to a MediaLink or IP Link control processor, as follows.
Connecting the MLA VC10 Plus to a MediaLink control processor
TIP: When connecting to a MediaLink control processor, Extron recommends using the
1. Connect the Transmit (Tx) socket on the rear panel of the MLA VC10 Plus to the
Receive (Rx) socket (labeled “A”) on the MediaLink control processor.
2. Connect the Receive (Rx) socket of the MLA VC10 Plus to the Transmit socket (labeled
“B”) on the MediaLink control processor (see gure 8 below).
3. Connect the ground (G) socket of the MLA VC10 Plus to the ground socket of the
MediaLink control processor.
MLS port, as shown in
figure 8, although other serial ports may also be used.
RS-232
Tx Rx G
Ground (G)
Tx - Rx
Rx - Tx
COM1
COM2
Tx
Rx
AB
+12V IN
GROUND
GROUND
MLS PWR
RS-232 12V
MLC 104 IP Plus
Serial Port
OR
TX RX TX RX
IPL T SFI244
Serial Port
Figure 8. Connecting an Extron Control Processor to the MLA VC10 Plus
MLA VC10 Plus • Installation and Cabling13
Connecting the MLA VC10 Plus to an IP Link control processor
Extron MLA VC10 Plus
Figure 8 also shows how to connect the MLA VC10 Plus to COM port 1 of the
IPL T SFI244. Connecting to other IP Link control processors is very similar.
1. Connect the Transmit (Tx) socket on the rear panel of the MLA VC10 Plus to the
Receive (Rx) socket of an IP Link control processor.
2. Connect the Receive (Rx) socket of the MLA VC10 Plus to the Transmit (Tx) socket of
an IP Link control processor.
3. Connect the ground (G) socket of the MLA VC10 Plus to the ground ( ) socket of the
IP Link control processor. If another device is using COM port 2 of the controller, it
may be necessary to splice the ground wires together.
Connections to a Third-party Control System
Third-party control systems issue SIS commands to the MLA VC10 Plus. For a list of SIS
commands, see the “Command and Response Table for SIS Commands” on page 33.
If the MLA VC10 Plus is to be connected to a third-party control device:
1. Connect the transmit socket (Tx) on the rear panel of the MLA VC10 Plus to the
receive socket of the control device.
2. Connect the receive socket (Rx) of the MLA VC10 Plus to the transmit socket of the
control device.
3. Connect the ground socket (G) of the MLA VC10 Plus to the ground socket on the
control device.
RS-232
Tx Rx G
Ground (G)Ground
Receive (Rx)
Transmit (Tx)
Transmit (Tx)
Receive (Rx)
Rx Tx Gnd
RS-232 Port of
Third-Party Control System
Figure 9. Connecting a Third-party Control System to the MLA VC10 Plus
MLA VC10 Plus • Installation and Cabling14
Relay
Extron MLA VC10 Plus
Extron MLA VC10 Plus
Mute Control
1. Consult the user guide for the amplifier to see whether
2. Connect the three-pole, 3.5 mm captive screw Relay
NOTE: By default, the Auto Mute feature of the MLA VC10 Plus automatically triggers
the relay when the volume level reaches 0%. If you use a controller to trigger
the relay instead, this Auto Mute feature must be disabled by SIS command
(see page 35).
mute control is available with the amplifier and whether
RELAY
the mute terminals need to be opened or closed for mute
to be activated. In most cases, amplifiers will require the
NONCC
NO pin to be used.
connector to the amplifier. The examples below show
the MLA VC10 Plus connected to the Paso DMS 3040
amplifier.
Other Uses
ATTENTION: Different manufacturers mark the
connections differently. The amplifier
shown in the figure at the right is
an example. To avoid damage to the
UNMUTE
MIC 1G M2 M1 RV CRVC
amplifier, ensure the wiring is correct
for the amplifier you are using.
Paso DMS 3040 Amplifier
The relay can be used for any general purpose relay control once
the Auto Mute function (enabled by default) has been disabled
by SIS commands.
One common example is to put the amplifier into standby mode,
for conserving power, as shown with the Extron XPA 1002
amplifier in the figure at right.
Connect the RS-232 control processor to the MLA VC10 Plus and
configure the mute function (see the user guide for the control
processor for instructions).
MASTER
REMOTE
10V
VOLUME
MUTE 1
MUTE 2
RELAY
NO NCC
50mA
G
GCV
GROUND
Extron XPA 1002
STANDBY
MLA VC10 Plus • Installation and Cabling15
Software Control
Software is not normally required to operate the MLA VC10 Plus. However, to congure
the unit or update the firmware, this section provides essential information.
zComputer Requirements
zAbout the Software
zAbout the Firmware
Computer Requirements
The minimum requirements for the PC are:
zWindows
zIntelzAt least 64 MB of RAM DevicezAt least 10 MB of Hard Disk spacezThe MLA VC10 Plus must be directly connected to the computer through the rear
panel RS-232 captive screw connectors or the front panel USB port.
®
XP, Service Pack 2, Windows Vista®, Windows 7, or later
®
Pentium® II processor with a 400 MHz clock speed or faster
About the Software
In most cases, the MLA VC10 Plus will work with the factory default settings and will
not require further conguration. If necessary, the MLA VC10 Plus can be controlled and
congured using the Extron SIS commands (see page 31).
To congure the MLA VC10 Plus, using SIS commands, Extron recommends that you install
the DataViewer program on your PC. This is provided on the disc that ships with the unit.
It can also be downloaded, free of charge, from the Extron website (www.extron.com).
For instructions about installing DataViewer, see “Software Installation” on page 18.
MLA VC10 Plus • Software Control16
Activating the USB Port for the First Time
NOTE: When DataViewer is installed on your computer, the Extron USB Driver is
installed at the same time. This driver is required to connect your computer to
any Extron product with a USB port.
When the USB connection is made, the Found New Hardware Wizard opens automatically.
1
1
Figure 10. Hardware Wizard — 1
1. Select No,notthistime and click Next.
The second Hardware Wizard screen opens:
2
2
Figure 11. Hardware Wizard — 2
2. Select Installthesoftwareautomatically and click Next.
Follow the on-screen instructions. The wizard installs the driver necessary to access the
MLA VC10 Plus USB port (this may take a few minutes).
3. Click Finish to exit the wizard.
Using DataViewer
To use DataViewer, see the help le that comes with the program. The help le can be
accessed by opening the program and either press the <F1> key or clicking on Use help in
the Help menu.
MLA VC10 Plus • Software Control17
Conguring the Extron Controller
Extron controllers may need be congured to work with the MLA VC10 Plus. The
appropriate software ships with the controller. For complete configuration instructions, see
the user guide for your Extron controller and the help le for the appropriate software.
An MLA VC10 Plus serial driver is available for easy conguration of Extron control
processors. Follow these instructions to download the driver.
1. On the device drivers page of the Extron website, select the name of your control
processor from the dropdown menu.
2. Select Extron from the Manufacturer dropdown menu.
3. When the page refreshes, select MLA VC10 Plus from the Model dropdown menu.
4. Click on Extron - MLAVC10Plus. Follow the instructions in the user guide for your
control processor to install the driver.
Software Installation
Insert the disc provided into the DVD ROM drive of your computer. If the setup program
does not start automatically, run Launch.exe from the DVD ROM directory in Windows
“My Computer.” Select the Software tab, locate the software you wish to download and
click Install. Follow the on-screen instructions to install the program.
Alternatively, go to the Extron website, click on the Download tab, and click on the
Software option in the left sidebar. Navigate to the software you wish to download and
click Download. Follow the on-screen instructions to install the program.
The Installer program creates a folder to contain the newly installed program. By default, it
is within the C:\Program Files\Extron\ folder to contain the Setup and Control Software. An
icon may also be placed on the Windows desktop.
About the Firmware
Downloading the Firmware
The MLA VC10 Plus ships with factory-installed rmware. The rmware is also available
on the DVD that is shipped with the MLA VC10 Plus. You can use SIS commands to check
which firmware version is installed on your volume control module (see page 36).
Occasionally, upgraded firmware is placed on our website for free download. Check the
Extron website (www.extron.com) periodically to see if upgrades are available.
1. Click on the Download tab at the top of the Extron home page. The Download Center
page opens.
2. Click Firmware in the menu bar on the left of the page.
3. Navigate to the MLA VC10 Plus.
4. Check the firmware version that is available for download.
NOTE: The firmware release notes are a PDF file that provides details about the
changes between different firmware versions. The file can be downloaded
from the same page as the firmware, on the Extron website.
MLA VC10 Plus • Software Control18
5. If the version available for download is more recent than the version on your volume
control module, click Download and follow the on-screen instructions. The file will be
downloaded to your computer. Make a note of the folder where it is saved.
NOTE: Upgrading your firmware requires the Extron Firmware Loader software to
be installed on the computer. The software is available for free download
from the Extron website (see “Software Installation,” on page 18).
Installing the Firmware
1. Open Firmware Loader and establish a connection between the computer and the
MLA VC10 Plus, using the USB or captive screw RS-232 connectors.
2. Follow the instructions in the Firmware Loader help file to install the firmware on the
volume control module.
Resetting to the Factory Installed Firmware
1. Power off the device.
2. Press and hold the reset button (e in figure 2) while applying power.
3. Once the power and activity LED lights (a in figure 2), release the reset button.
NOTE: Firmware reset only restores the factory installed firmware. It does
not alter other configurable settings. These must be reset using SIS
commands.
MLA VC10 Plus • Software Control19
Operation
This section of the guide describes
zOperation
zTroubleshooting
Operation
The Extron MLA VC10 Plus Volume Control Module converts RS-232 commands from a
control system into voltage or impedance changes to control audio amplifiers with volume
and mute control ports. The MLA VC10 Plus is used to mute or make level changes on
an Extron MPA Series or half-rack XTRA™ Series amplifier from a TouchLink™ Touchpanel
system, an RS-232-capable MediaLink® Control Processor, or other third-party control
system. The control module also supports third-party amplifiers that use either voltage or
potentiometer control.
SIS commands from the RS-232 port can also be used to control the relay switch for audio
mute or some other purpose.
Voltage or Resistance Control
The MLA VC10 Plus controls the volume of an audio amplier by regulating either:
zVariable DC voltage (up to a maximum of 10 VDC in 100 increments).
zResistance (up to a maximum 10 kilohm in 100 increments).
The MLA VC10 Plus uses 8-bit resolution to set the volume range, providing 256 available
steps, although only 100 will always be used. If the maximum resistance (or voltage range)
is set to 4 kilohm (or 4 VDC), only 40% of the total possible steps (102) are available.
Below 4 kilohm or 4 VDC, you will no longer have true 100-step resolution as some of
the 100 steps will be repeated. Below 2 kilohms or 2 VDC, you may start to hear audible
jumps in the audio volume. The 100 steps here refer to the 100 SIS volume control
commands
Determine whether the amplifier you are using is controlled by voltage or resistance and
use SIS commands to set the control mode to voltage or resistance (default). Connect the
amplier to the appropriate port (see “Connections for volume control by voltage” on
page 9).
NOTES:• Only one port (voltage or resistance) is active at any one time. By default,
this is the resistance control port. In addition to physically wiring the
amplifier to the correct control port, you must use SIS commands to set the
correct control mode.
• All Extron amplifiers and the majority of third-party amplifiers researched and
tested by Extron work with the MLA VC10 Plus straight from the box, using
10 kilohm resistance control, without further configuration.
MLA VC10 Plus • Operation20
Maximum voltage range limit
Some ampliers use a maximum voltage that is lower than 10 VDC. Using a voltage that
exceeds the requirements of the amplier can damage the equipment. Using a voltage
that is lower than the requirements of the amplifier will limit the maximum audio volume
reached. Determine what the maximum signal requirements are for the amplifier you are
using and use SIS commands to set the maximum control voltage that can be provided by
the MLA VC10 Plus.
ATTENTION: If you are controlling the volume using voltage, be sure that you know
the control voltage range for the amplifier that you are using. Consult
the user guide for the amplifier you are using or measure it, following
the instructions starting on page 8. Setting the control voltage too
high for the amplifier may damage that equipment.
The MLA VC10 Plus can control ampliers that use a maximum control voltage that is
greater than 10 VDC but the maximum volume for the amplier may not be reached.
Maximum resistance range limit
Some amplifiers use a maximum resistance that is lower than 10 kilohms. Determine the
requirements for the amplifier and, if necessary, set the values using SIS commands
(see page 35).
NOTE: All Extron amplifiers use the default 10 kilohms resistance control.
The resistance between the reference (V) and ground (G) pins of the MLA VC10 Plus is
always 10 kilohms. When a maximum range limit is applied to the resistance control, it
only limits the maximum resistance across the wiper (C) and ground (G) pins. This usually
limits the maximum volume output from the amplifier.
If using 3-pin potentiometer control to connect to an amplifier that requires a total
resistance of anything other than 10 kilohms, Extron still recommends that the 10 kilohms
setting be used to ensure full volume range.
Inverse Mode
By default, when the voltage is 0 VDC or the resistance is 0 ohm, the volume is considered
muted. At 10 VDC or the resistance is 10 kilohm, the volume is considered maximum.
Some amplifiers reverse their voltage or resistance requirements. Maximum volume is at
0 VDC or 0 ohm and the minimum volume (mute) at 10 VDC or 10 kilohm. For these
amplifiers, the volume control knob on the RS-232 control processor works counterintuitively: turning it clockwise decreases the volume and turning it counterclockwise
increases the volume.
Inverse mode reverses the resistance or voltage control signal sent to these amplifiers
so that the volume control knob on the RS-232 control processor works the way the
user expects: clockwise decreases the voltage or resistance, but increases the volume,
counterclockwise increases the voltage or resistance, but decreases the volume.
NOTE: Inverse mode should be disabled (the default setting) for all Extron amplifiers.
The inverse mode can be turned on or off (default), using SIS commands (see page 35).
MLA VC10 Plus • Operation21
Linear or Logarithmic Taper Mode
The MLA VC10 Plus is set to linear taper by default. Each increment or decrement will
change the voltage or resistance by a constant amount. In logarithmic taper mode, the
volume control module modifies the steps to increase or decrease the voltage or resistance
logarithmically.
When the amplier increases the power provided to the speakers in logarithmic
increments, the human ear hears a linear change in sound volume. Some amplifiers
provide this compensation internally and work best if the MLA VC10 Plus uses the linear
taper mode. Amplifiers that do not provide their own compensation will sound better if
the MLA VC10 Plus uses logarithmic taper mode.
NOTE: This feature should be set to linear taper mode (the default setting) for all
Extron amplifiers.
The volume taper can be set to linear (default) or logarithmic mode using SIS commands
(see page 35).
Auto Mute
By default, the relay is used for the Auto Mute function. The relay automatically triggers
on whenever the volume level on the MLA is zero. For a third-party amplifier that has
contact closure terminals, the relay can be used to mute the audio.
To use a RS-232 control device to switch the relay on or off for other purposes, the auto
mute function must be disabled (see the SIS commands on page 35).
Soft Start
Troubleshooting
After a power cycle or unmuting the MLA, the audio level returns to its previous value.
When soft start is enabled (the default setting), the audio level rises slowly after a power
cycle or a mute, to avoid abrupt changes in power to the speakers. This can prevent
damage to equipment and loud bursts of audio. The rate of volume increase can be set by
SIS commands (see page 35).
For example, if the volume is currently at 50%, when the audio is muted or the unit goes
through a power cycle, the volume will decrease to 0% immediately. When the audio is
un-muted, the volume increases slowly from 0 to 50% over a few seconds.
NOTE: If the Auto Mute feature is on (default setting), the relay will also be triggered
when the volume is muted.
The soft start mode can be turned on (default) or off, using SIS commands (see page 35).
If you have problems with the MLA VC10 Plus, try some of these suggestions.
The MLA VC10 Plus is not receiving power
zCheck the Power and Activity LED (a in figure 2) — it is lit when the unit is
receiving power.
zCheck the wiring at the power port of the MLA VC10 Plus for the correct polarity
(see page 11).
zVerify that the power supply has been connected to a functional power outlet.
MLA VC10 Plus • Operation22
The MLA VC10 Plus does not respond to SIS commands
zCheck the Power and Activity LED (a in figure 2) — it flashes green when SIS
commands are received.
zThe MLA VC10 Plus may not be receiving RS-232 commands correctly. Check the
connections between the control device and the MLA VC10 Plus. Ensure the Tx
and Rx wiring is not reversed (see pages 13 and 14).
zCheck the baud rate is 9600 bps, 8 data bits, 1 stop bit, no parity.
There is no audio output
zCheck that the master volume on the amplifier is not set to minimum.zCheck the wiring to the amplier or mixer to make sure the MLA VC10 Plus is
connected to the correct remote volume terminals (see page 6 if using resistance
control or page 8 if using voltage control).
zVerify that all the equipment is powered on.zEnsure the front panel USB connection is removed and recycle power to the 12 VDC
port only (f in the rear panel diagram on page 4).
zCheck the mute LED (b in figure 2). It lights solid green when the volume is set to 0
or muted. Use SIS commands to increase the volume level (see page 33).
zCheck that the correct control mode (voltage or potentiometer) is selected. If
necessary, use SIS commands to change to the correct control mode (see page 35).
zIf the relay is connected to mute control, check the relay LED (c in figure 2) to
see whether the relay is on. Use SIS commands to turn the relay off (page 34) or
increase the volume level (page 33).
The MLA VC10 Plus does not provide a good volume sweep range (cannot reach
maximum volume or there is no volume change in a certain range)
zEnsure the amplier gain is set correctly. If the amplier has a master volume knob,
this must be set to the maximum desired level.
zEnsure that the proper control mode, required by the amplifier, has been set.zEnsure the correct maximum voltage, required by the amplifier, has been set.zWhen a maximum range limit is applied to the resistance control, it only limits the
maximum resistance across the wiper (C) and ground (G) pins. This usually limits the
maximum volume output from the amplier. The resistance between the reference (V)
and ground (G) pins of the MLA VC10 Plus is always xed at 10 kilohms.
Extron recommends that for three-terminal potentiometer control, the maximum
resistance output should remain at 10 kilohm, to provide the optimum volume range.
NOTE: Some amplifiers do not obtain good maximum or minimum volume
control through their remote volume terminals.
The output is noisy or has static
zIt may be necessary to move the amplier or mixer and MLA VC10 Plus away from
sources of electromagnetic interference, such as appliances and large motors.
zIf the voltage control cable is too long, noise may be picked up from many sources.
Use a shielded cable that is no longer than 6 feet between the MLA VC10 Plus and
the amplier. For best results, Extron recommends placing the MLA VC10 Plus as close
as possible to the amplifier.
MLA VC10 Plus • Operation23
zThe ground line may be noisy. Use a different, “clean” grounding source. The chassis
of the MediaLink controller (if used), the power supply, the MLA VC10 Plus, and the
amplifier or mixer should all share a common ground.
The audio output can still be heard when the MLA VC10 Plus has a volume setting
of 0 VDC
zCheck the gain and level settings on the amplifier or mixer. Adjust the gain so that you
do not hear any audio output when the MLA VC10 Plus is set for minimum volume.
zThe variable voltage or resistance ports on the MLA VC10 Plus do not always reach
the absolute minimum or maximum. Therefore, if the audio amplifier has remote mute
capability, use the contact closure relay switches on the MLA VC10 Plus.
NOTE: Some amplifiers do not obtain good maximum or minimum volume
control through their remote volume terminals.
The volume does not change when you change the volume setting via the MLC or
via the RS-232 commands:
zCheck Power and Activity LED (a in figure 2) — it blinks green when commands
are received.
zEnsure the front panel USB connection is removed and recycle power to the 12 VDC
port only (a in the rear panel diagram on page 4).
zThe wiring at the amplifier or mixer terminals may be incorrect.
zCheck that RS-232 settings are 9600 bps, 8 data bits, 1 stop bit, no parity.
zCheck that the correct control mode (voltage or potentiometer) has been set on
the MLA VC10 Plus (see page 35). Only one port can be active at a time.
zThe maximum output voltage or resistance may be set incorrectly. Retest the control
voltage of the amplifier or check the user guide for the amplifier to verify the
maximum voltage. Reset the maximum output voltage or resistance as required
(see page 35).
zThe amplier may accept a higher control voltage than the MLA VC10 Plus provides,
so the amplifier will not reach its highest volume level.
zTest the equipment with another amplifier.
The volume level from the amplifier changes in the opposite direction to the knob
on the controller.
zCheck the wiring to ensure that the pins for resistance or voltage control are
connected appropriately (see page 6 if using resistance or page 8 if using voltage).
zCheck the user guide of the amplifier to see whether it should be controlled by
inverse mode. If so, use SIS commands to enable or disable inverse mode on the
MLA VC10 Plus (see page 35).
There is no voltage or resistance change or no output from the MLA VC10 Plus
control ports.
zEnsure the front panel USB connection is removed. Shut off the device and reapply
power to the 12 VDC port only (f in the rear panel diagram on page 4).
zCheck that the correct control mode (voltage or potentiometer) has been set on
the MLA VC10 Plus (see page 35). Only one port can be active at a time.
If you have other problems, or for further advice, contact the Extron support staff (see
the contact information on the back page of this user guide).
MLA VC10 Plus • Operation24
Specications
Control/remote — MLA volume controller
Serial control port ........................... 1 RS-232, 3.5 mm captive screw connector, 3 pole
Baud rate and protocol ................... 9600 baud, 8 data bits, 1 stop bit, no parity
Serial control pin configuration ....... 1 = Tx, 2 = Rx, 3 = GND
USB control ports ........................... 1 front panel female mini USB B
USB standards ................................ USB 2.0, low speed
NOTE: The USB connector provides 5 VDC for configuration purposes only. This port cannot be used to supply
power during normal operation.
Program control ............................. Extron Simple Instruction Set (SIS
Control — variable voltage — amplier
Number/type .................................. 1 control voltage
Connectors .................................... (1) 3.5 mm captive screw connector, 2 pole
MBU 125 under-desk mounting kit70-077-01
MBD 129 through desk mounting kit70-077-02
MLA VC10 Plus • Parts and Accessories27
Reference
Material
Control Resistance and Voltage for Common Amplifiers
The table below shows the control resistance and control voltage requirements for a selection of
common ampliers. The MLA VC10 Plus is compatible with a wide range of ampliers. The models
shown in this table are included as examples only. The MLA VC10 Plus is not limited to working
with only the amplifiers shown in this guide. The majority of amplifiers researched and tested by
Extron work with the MLA VC10 Plus straight from the box, using 10 kilohm resistance control.
ATTENTION: Extron has attempted to ensure that these specications are accurate. However,
they may change without notice. Using a control voltage that is too high will
damage the amplifier. Always verify the control voltage by checking the user
guide for the amplifier or measuring it yourself.
Wiring may use two terminals (A in the Wiring column) or three terminals (B in the Wiring column).
Manufacturer ModelControl Resistance Control VoltageWiring
900 Series (H-21)0 - 10 kilohmA
900 Series (H-22)0 - 10 kilohmA
900 Series (X-21)0 - 10 kilohmA900 Series (V-01S)0 - 10 kilohmA
9000 Series0 - 10 kilohm10 VDCA
MLA VC10 Plus • Reference Material30
SIS Commands
This section provides information about the Extron Simple Instruction Set (SIS) commands
that are used to congure the MLA VC10 Plus:
zIntroduction to SIS
zSymbols Used in this Guide
zError messages
zCommand/Response table for SIS commands
Introduction to SIS
The MLA VC10 Plus accepts SIS commands from a control device connected to the RS-232
3-pin captive screw connector on the rear panel or to the female mini B USB port on the
front panel.
NOTES:• The wiring in the RS-232 cables crosses over so that the Tx of one device
connects to the Rx of the other and vice versa.
• Neither port takes precedence over the other. Commands are always
processed in the order that they are received.
The RS-232 protocol is 9600 baud, 8 data bit, 1 stop bit, and no parity.
SIS commands consist of a string (one or more characters per command eld). Unless
otherwise stated, upper and lower case characters may be used interchangeably.
When a command is valid, the MLA executes that command and sends a response to
the host device. Commands do not require any special characters to begin or end the
command string. Each response from the MLA VC10 Plus ends with a carriage return and
a line feed (CR/LF =
When the MLA VC10 Plus is rst switched on, it sends the message:
X& — Firmware version number (in the format: x.xx)
X* — The unit name is an alphanumeric string of up to 24 characters that allows the user
MLA VC10 Plus • SIS Commands32
Error Messages
to uniquely identify the unit within the system. For example, it could be the room number.
The default name is MLA-VC10-PLUS.
NOTES:• Only letters (A-Z), numbers (0-9), and the hyphen (minus sign) are valid.
• No blank or space characters are permitted.
• No distinction is made between upper and lower case letters.
• The first character must be a letter.
• The final character cannot be a hyphen (minus sign).
X( — Soft start delay in milliseconds per volume step (40 ms to 200 ms). Default is 40,
which is equivalent to 40 ms.
When the MLA receives a valid SIS command, it executes the command and sends a
response to the host device. If the MLA is unable to execute the command because the
command contains invalid parameters, it returns the following error response to the host:
E10 = Invalid commandE14 = Not valid for this config.
E13 = Invalid parameter
If the MLA VC10 Plus does not support or recognize the entered commands, nothing will
happen and no response is issued.
Command and Response Table for SIS Commands
CommandASCII Command
(host to unit)
Volume Adjustment
Setoutputvolume
Example:
Increment
Decrement
View
NOTE: Whenever another SIS command results in a change in volume, the Volume response (VolX!]) will
volume
volume
currentvolume
be given as an unsolicited response.
X! VVolX!]Specifies the volume level (X! 0 to 100).
82V
+V
-V
V
Response
(unit to host)
Vol082
Vol
Vol
Vol
]
X!]
X!]
X!]
Additional Description
Setsthevolumelevelto82
Increment audio volume (+1).
Decrement audio volume (-1).
Show the current audio volume.
MLA VC10 Plus • SIS Commands33
CommandASCII Command
(host to unit)
Response
(unit to host)
Additional Description
Audio Mute
Muteon
Muteoff
View currentaudiomute
status
NOTE: Whenever another SIS command results in a change in mute status, the mute status response
(AmtX@]) will be given as an unsolicited response.
1Z
0Z
Z
]
Amt1
]
Amt0
X@]Show current audio mute setting (X@)
Amt
Mute audio output volume to 0; toggle
relay on if Auto Mute is enabled.
Un-mute audio and return volume to its
previous level; toggle relay off if Auto
Mute is enabled.
0 = Off (Disabled)
1 = On (Enabled)
Relay
NOTE: By default, the relay is set to trigger on automatically when the volume level is set to 0 (mute). To use
the relay for other purposes, the Auto Mute function must be disabled.
on
Relay
off
Relay
relay
Toggle
relay
Pulse
View relay
1*1O
1*0O
1*2O
1*3*X#ORly1*X@]
1O
Rly1*1
Rly1*0
Rly1*
Rly1*X@]
Rly1*
]
]
X@]
X@]
Set relay on.
Set relay off.
Toggle relay.
Set relay pulse time (X# is an integer
multiple of 20 ms increments: if X#
is 12 (the minimum value), this is
equivalent to 12*20 = 240 ms).
This command gets two responses: one
at the start of the pulse, the other at
the end of the pulse.
Reports back the current relay status.
MLA VC10 Plus • SIS Commands34
CommandASCII Command
(host to unit)
Response
(unit to host)
Additional Description
Voltage and Potentiometer Adjustment
Setthemaximumvoltage
outputlevel
NOTE: The device control mode must be set to voltage before this command can be used.
View
maximumvoltage
outputlevel
Setthepotentiometer
maximumresistance
output
NOTE: The device control mode must be set to potentiometer before this command can be used.
thepotentiometer
View
maximumresistance
output
EV*X$VLCM}Vlcm•VX$]
VolX!]
EVVLCM}Vlcm•VX$]X$ is returned in four digits with no
EP*X$VLCM}Vlcm•PX$]
VolX!]
EPVLCM}Vlcm•PX$]X$ is returned in four digits without a
Set the maximum voltage output level.
(X$ = 0.04 to 10.00 V; default is 10 V.)
The volume status (X!) is reported even
if there is no change in volume.
decimal point.
Sets the maximum resistance output
on the wiper ( ) pin. (X$ = 0.00 to
10.00 kilohm; default is 10 kilohm.)
The volume status (X!) is reported even
if there is no change in volume.
decimal.
Modes
Setcontrolmode
View controlmode
Setinversemode
View inversemode
Setsoftstartmode
View softstartmode
Setsoftstartdelay
View softstartdelay
Setautomutemode
View automutemode
EM*X%VLCM}Vlcm•MX%•]
VolX!]
Control mode status (X%)
0 = potentiometer (default)
1 = voltage
EMVLCM}Vlcm•MX%•]
EI*X@VLCM}Vlcm•IX@•]
VolX!]
EIVLCM}Vlcm•IX@•]
Inverse mode status (X@)
0 = Off (default)
1 = On
If Inverse mode is off, returns 0;
if Inverse mode is on, returns 1.
ES*X@VLCM}Vlcm•SX@•]Soft start mode status (X@)
0 = Off
1 = On (default)
ESVLCM}Vlcm•SX@•]
ED*X(VLCM}Vlcm•DX(]Soft start delay — X( ms per volume
EDVLCM}Vlcm•DX(]
step 40 ms (default) to 200ms
EA*X@VLCM}Vlcm•AX@•]Auto mute mode status (X@)
0 = Off
1 = On (default)
EAVLCM}Vlcm•AX@•]
Setvolumetapermode
View volumetapermode
EL*X^VLCM}Vlcm•LX^•]
VolX!]
ELVLCM}Vlcm•LX^•]
Volume taper mode status (X^)
0 = Linear
1 = Logarithmic
settings to the factory defaults.
Maintains voltage and resistance
outputs and device name.
Resets all configurable settings, device
name, outputs, and flash memory to
factory defaults.
NOTE: This command does not
reset firmware to the
factory default.
Shows firmware version in format x.xx
string of up to 24 characters that allows
the user to uniquely identify the device.
The default name is MLA-VC10-PLUS.
Shows the model name.
Shows the part number.
MLA VC10 Plus • SIS Commands36
Mounting
This section outlines the various mounting options available for the MLA VC10 Plus:
zTabletop Placement
zRack Mounting
zUnder-desk Mounting
zThrough-desk Mounting
Tabletop Placement
Attach the four provided rubber feet to the bottom of the unit and place it in any suitable
location.
Rack Mounting
UL Guidelines for Rack Mounting
The following Underwriters Laboratories (UL) guidelines are relevant to the safe installation
of this product in a rack:
1. Elevated operating ambient temperature — If the unit is installed in a closed or
multi-unit rack assembly, the operating ambient temperature of the rack environment
may be greater than room ambient temperature. Therefore, install the equipment in
an environment compatible with the maximum ambient temperature (TMA: +122 °F,
+50 °C) specied by Extron.
2. Reduced air flow — Install the equipment in the rack so that the equipment gets
adequate air flow for safe operation.
3. Mechanical loading — Mount the equipment in the rack so that uneven mechanical
loading does not create a hazardous condition.
4. Circuit overloading — Connect the equipment to the supply circuit and consider the
effect that circuit overloading might have on overcurrent protection and supply wiring.
Appropriate consideration of the equipment nameplate ratings should be used when
addressing this concern.
5. Reliable earthing (grounding) — Maintain reliable grounding of rack-mounted
equipment. Pay particular attention to supply connections other than direct
connections to the branch circuit (such as the use of power strips).
MLA VC10 Plus • Mounting37
Rack Mounting Procedure
The unit can be mounted on any of these optional Extron rack systems:
zRSF 123 — 3.5 inch deep, 1U universal rack shelf kit (part number 60-190-20)zRSB 123 — 3.5 inch deep, 1U basic rack shelf (part number 60-604-21)zRSU 126 — 6 inch deep, 1U universal rack shelf kit (part number 60-190-10)zRSB 126 — 6 inch deep, 1U basic rack shelf (part number 60-604-11)zRSU 129 — 9.5 inch deep, 1U universal rack shelf kit (part number 60-190-01)zRSB 129 — 9.5 inch deep, 1U basic rack shelf (part number 60-604-02)
To mount the unit on a rack shelf, follow the instructions provided with the shelf
accessories.
Under-desk Mounting
Mount the unit under a desk or podium, using the optional Extron MBU 125 under-desk
mounting kit (part number 70-077-01) by following the instructions provided with the
MBU 125 kit.
Through-desk Mounting
Mount the unit through a desk or podium using the optional Extron MBD 129 through
desk mounting kit (part number 70-077-02) by following the instructions provided with
the MBD 129 kit.
MLA VC10 Plus • Mounting38
Extron Warranty
Extron Electronics warrants this product against defects in materials and workmanship for a period of three years
from the date of purchase. In the event of malfunction during the warranty period attributable directly to faulty
workmanship, materials or both, Extron Electronics will, at its option, repair or replace said products or components,
to whatever extent it shall deem necessary to restore said product to proper operating condition, provided that it is
returned within the warranty period, with proof of purchase and description of malfunction to:
USA, Canada, South America,
and Central America:
Extron Electronics
1001 East Ball Road
Anaheim, CA 92805
U.S.A.
Europe and Africa:
Extron Europe
Hanzeboulevard 10
3825 PH Amersfoort
The Netherlands
Japan:
Extron Electronics, Japan
Kyodo Building, 16 Ichibancho
Chiyoda-ku, Tokyo 102-0082
Japan
China:
Extron China
686 Ronghua Road
Songjiang District
Shanghai 201611
China
Asia:
Extron Asia
135 Joo Seng Road, #04-01
PM Industrial Bldg.
Singapore 368363
Middle East:
Extron Middle East
Dubai Airport Free Zone
F12, PO Box 293666
United Arab Emirates, Dubai
Singapore
This Limited Warranty does not apply if the fault has been caused by misuse, improper handling care, electrical or
mechanical abuse, abnormal operating conditions, or if modifications were made to the product that were not
authorized by Extron.
NOTE: If a product is defective, please call Extron and ask for an Application Engineer to receive an RA (Return
Authorization) number. This will begin the repair process.
USA: 714.491.1500 or 800.633.9876 Europe: 31.33.453.4040
Asia: 65.6383.4400 Japan: 81.3.3511.7655
Units must be returned insured, with shipping charges prepaid. If not insured, you assume the risk of loss or damage
during shipment. Returned units must include the serial number and a description of the problem, as well as the
name of the person to contact in case there are any questions.
Extron Electronics makes no further warranties either expressed or implied with respect to the product and its quality,
performance, merchantability, or fitness for any particular use. In no event will Extron Electronics be liable for direct,
indirect, or consequential damages resulting from any defect in this product even if Extron Electronics has been
advised of such damage.
Please note that laws vary from state to state and country to country, and that some provisions of this warranty may
not apply to you.
Extron Headquarters
+1.800.633.9876 (Inside USA/Canada Only)
Extron USA - West Extron USA - East