The Extron ASA series high-performance audio summing amplifiers convert stereo audio signals into balanced or
unbalanced mono signals. The series consists of the following two models:
• ASA 204 — The ASA 204 has four independent active summing amps with four pairs of RCA connectors for
unbalanced line level stereo audio inputs. The unit has captive screw connectors for four balanced or unbalanced
mono outputs. Because of its input/output configuration, the ASA 204 can also function as an unbalanced to
balanced audio converter.
• ASA 304 — The ASA 304 has four independent active summing amps with four 5-pole captive screw connectors
for balanced or unbalanced line level stereo audio inputs. The unit has captive screw connectors for four balanced or
unbalanced mono outputs.
The ASA 204 and ASA 304 include an external 12V power supply that accepts 100-240VAC input.
Features
• Four, independent active audio summing amplifiers in a single enclosure
• Stereo inputs on RCA connectors, mono output on captive screw connectors
• Converts stereo audio to balanced or unbalanced mono audio
• ±6 dB output gain switch
• Rack-mountable 1U, quarter rack width metal enclosure
• Extron Everlast Power Supply (included) is covered by a 7-year parts and labor warranty
Installation and Operation
Mounting the ASA 204 and ASA 304
The ASA 204 and ASA 304 can be set on a table, or mounted on a rack shelf, under a desk or tabletop, or on a projector
mount.
Tabletop placement
Attach the four provided rubber feet to the bottom of the unit and place it on a convenient tabletop location.
Rack mounting
For optional rack mounting, do not install the rubber feet. Mount the ASA on a 19” 1U rack shelf or a standard universal
1U rack shelf. On the standard rack shelf, the ASA mounts in one of four locations to the rear of the rack or in one of four
locations to the front of the rack.
1. Remove rubber feet if they were previously installed on the
bottom of the ASA.
2. Mount the ASA on the rack shelf, using two 4-40 x 3/16”
screws in opposite (diagonal) corners to secure the amplifier
to the shelf.
3. Install blank panels or other units on the rack shelf (see the
image on the right).
4. Attach the rack shelf to the rack using the supplied bolts.
NOTE: Most 1U rack-mountable Extron products can be
mounted on the standard shelf.
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ASA 204 and ASA 304 • User Guide (Continued)
11
POWER
12V
.2A MAX
STEREO INPUTS
MONO OUTPUTS
BAL
UNBAL
ON
SPARE
3
1
4
2
43
21
L
QUAD AUDIO
SUMMING
AMPLIFIERS
R
ASA
204
L
L
R
R
1122
3
3
4
4
Slee
No Ground Here
Unbalanced Audio InputBalanced Audio Input
Slee
Do not tin the wires!
ASA 204/ASA 304 Front Panel Features
Power LED — Lights to indicate that the ASA is on.
Wire the audio input and output connectors as shown at
right. Use the supplied tie wrap to strap the audio cable
to the extended tail of the connector.
Output gain DIP switch
3
Power connector
4
Tip
Ring
ves
Tip
Ring
Balanced Audio Output
Tip
Ring
ves
Tip
Ring
LR
LR
Tip
Sleeves
Tip
No Ground Here
Unbalanced Audio Output
Tip
Sleeve
Tip
Sleeve
LR
LR
Tip(L)
Ring(R)
Sleeve ( )
RCA Connector
ATTENTION:
• Connect the sleeve to ground (Gnd). Connecting the sleeve to a negative (-) terminal will damage the audio
output circuits.
• Connectez le manchon à la borne de terre (Gnd). Connecter le manchon à une borne négative(-) endommagera
les circuits de la sortie audio.
• For unbalanced outputs, do not connect wires to the “-” poles (see the Extron Audio Wiring Card).
• Pour les sorties asymétriques, ne connectez pas de câbles aux pôles « - » (voir le Audio Wiring Card d’Extron).
• The length of exposed wires is critical. The ideal length is 3/16 inch (5 mm).
2
• La longueur des câbles exposés est primordiale lorsque l’on entreprend de les dénuder. La longueur idéale est
de 5mm (3/16inches).
Page 3
Output gain DIP switch — Use this switch to set the audio output gain level.
Rear Panel
)
3
Gain levels available via the switch vary depending on whether both inputs are receiving signals, and on the output
wiring, as shown in the table below.
Input ChannelOutputOutput DIP Switch Settings
LeftRightWiringUnbalancedBalanced
signalsignalbalanced+9dB+3dB
signal——balanced+3dB-3dB
——signalbalanced+3dB-3dB
signalsignalunbalanced+3dB-3dB
signal——unbalanced-3dB-9dB
——signalunbalanced-3dB-9dB
Power connector — An external 12 V power supply is included with the unit. Plug it into this 2-pole captive screw
4
connector. Wire the connector as shown below.
Power Receptacle
DC Power Cord
Captive Screw
Connector
Ground
Smooth
all devices.
External
Power Supply
(12 VDC, 0.5 A max.
Ridged
– Return
+12 VDC input
Figure 4. Rear Panel 12 VDC Power Connector
CAUTION: The DC output cables must be kept separate from each other while the power supply is plugged in.
Remove power before wiring
AVERTISSEMENT : Les câbles de sortie CC doivent être séparés les uns des autres tant que la source
d’alimentation est branchée. Coupez l’alimentation avant d’effectuer les raccordements.
ATTENTION:
• Do not connect power to the amplifier until you have read the ATTENTION notifications.
• Ne branchez pas l’alimentation au l’amplificateur avant d’avoir lu les mises en garde « ATTENTION ».
• Always use a power supply supplied or specified by Extron. Use of an unauthorized power supply voids all
regulatory compliance certification and may cause damage to the supply and the end product.
• Utilisez toujours une source d’alimentation fournie ou recommandée par Extron. L’utilisation d’une source
d’alimentation non autorisée annule toute certification de conformité réglementaire et peut endommager la
source d’alimentation et l’unité.
• If not provided with a power supply, this product is intended to be supplied by a power source marked
“Class 2” or “LPS” and rated at 12VDC and a minimum of 0.5A.
• Si le produit n’est pas fourni avec une source d’alimentation, il doit être alimenté par une source
d’alimentation de classe 2 ou LPS, avec une tension nominale 12 Vcc, 0,5 A minimum.
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ATTENTION:
• The installation must always be in accordance with the applicable provisions of National Electrical Code
ANSI/NFPA 70, article 725 and the Canadian Electrical Code part 1, section 16. The power supply shall not
be permanently fixed to building structure or similar structure.
• Cette installation doit toujours être conforme aux dispositions applicables du Code américain de l’électricité
(National Electrical Code) ANSI/NFPA 70, article 725, et du Code canadien de l’électricité, partie1,
section16. La source d’alimentation ne devra pas être fixée de façon permanente à une structure de
bâtiment ou à une structure similaire.
• Power supply voltage polarity is critical. Incorrect voltage polarity can damage the power supply and the unit.
The ridges on the side of the cord (see figure4 on the previous page) identify the power cord negative lead.
• La polarité de la source d’alimentation est primordiale. Une polarité incorrecte pourrait endommager la
source d’alimentation et l’unité. Les stries sur le côté du cordon (voir figure4) permettent de repérer le pôle
négatif du cordon d’alimentation.
• To verify the polarity before connection, plug in the power supply with no load and check the output with a
voltmeter.
• Pour vérifier la polarité avant la connexion, brancher l’alimentation hors charge et mesurer sa sortie avec un
voltmètre.
• The length of the exposed (stripped) wires is important. The ideal length is 3/16inch (5mm). 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.
• La longueur des câbles exposés est primordiale lorsque l’on entreprend de les dénuder. La longueur idéale
est de 5mm (3/16inches). S’ils sont trop longs, les câbles exposés pourraient se toucher et provoquer un
court circuit. S’ils sont trop courts, ils peuvent être tirés facilement, même s’ils sont correctement serrés par
les borniers à vis.
• Unless otherwise stated, the AC/DC adapters are not suitable for use in air handling spaces or in wall
cavities.
• Sauf mention contraire, les adaptateurs CA/CC ne conviennent pas à une utilisation dans les espaces
d’aération ou dans les cavités murales.
• Remote power is intended for indoors use only. No part of a network that uses remote power can be routed
outdoors.
• L’alimentation à distance est exclusivement réservée à un usage en intérieur. Un réseau utilisant une
alimentation à distance ne peut pas être routé en extérieur.
For 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.