FOR-A ADA+205A Operation Manual

OPERATION
MANUAL

ADA-205A

Audio Distribution Amplifier

nd

Edition - Rev.2

2

Precautions

Important Safety Warnings
[Power]

Caution

Stop

[Grounding]

Operate unit only on the specified supply voltage.

Disconnect power cord by connector only. Do not pull on cable portion.

Do not place or drop heavy or sharp-edged objects on power cord. A damaged cord

can cause fire or electrical shock hazards. Regularly check power cord for
excessive wear or damage to avoid possible fire / electrical hazards.

Caution

Hazard

Caution

Ensure unit is properly grounded at all times to prevent electrical shock hazard.

Do not ground the unit to gas lines, units, or fixtures of an explosive or dangerous
nature.

Ensure power cord is firmly plugged into AC outlet.

[Operation]

Hazard

Hazard

Do not operate unit in hazardous or potentially explosive atmospheres. Doing so

could result in fire, explosion, or other dangerous results.

Do not allow liquids, metal pieces, or other foreign materials to enter the unit. Doing

so could result in fire, other hazards, or unit malfunction.

If foreign material does enter the unit, turn power off and disconnect power cord

immediately. Remove material and contact authorized service representative if
damage has occurred.

[Transportation]

Caution

Handle with care to avoid shocks in transit. Shocks may cause malfunction. When

you need to transport the unit, use the original packing materials or alternate
adequate packing.

[Circuitry Access]

Stop

Hazard

Do not remove covers, panels, casing, or access circuitry with power applied to the

unit! Turn power off and disconnect power cord prior to removal. Internal servicing /
adjustment of unit should only be performed by qualified personnel.

Do not touch any parts / circuitry with a high heat factor.

Capacitors can retain enough electric charge to cause mild to serious shock, even
after power is disconnected. Capacitors associated with the power supply are
especially hazardous. Avoid contact with any capacitors.

Unit should not be operated or stored with cover, panels, and / or casing removed.

Operating unit with circuitry exposed could result in electric shock / fire hazards or
unit malfunction.

[Potential Hazards]

Caution

If abnormal smells or noises are noticed coming from the unit, turn power off
immediately and disconnect power cord to avoid potentially hazardous conditions. If

problems similar to above occur, contact authorized service representative before

attempting to again operate unit.

[Consumables]

Caution

The consumables used in unit must be replaced periodically. For further details on
which parts are consumables and when they should be replaced, refer to the
specifications at the end of the Operation Manual. Since the service life of the
consumables varies greatly depending on the environment in which they are used,
they should be replaced at an early date. For details on replacing the consumables,
contact your dealer.

[Rubber Feet]

Caution

If this product has come with rubber feet attached by screws, do not insert the
screws again without rubber feet after removing the rubber feet and screws. It may
cause damage to the internal circuits or components of the unit. To install the rubber
feet again to the unit, do not use other than the supplied rubber feet and screws.

General Considerations

Power Supply

Verify your unit has the correct voltage specifications for your power source prior to applying
power by reading the voltage range on the rear panel near the AC connector. The ADA-205A
normally operates on 100/117VAC or 220-240VAC ±10%; 50/60Hz. Do not attempt to operate
the ADA-205A using a source having different specifications.

Location

Avoid using the ADA-205A in areas having high humidity, high temperature, or excessive dust.
Adequate ventilation is also required for optimum performance. As a result of this consideration,
ensure no other equipment is located, or installed, closer than 5cm to any unit.

Desk or Tabletop Use

Unit baseplate is fitted at the factory with rubber feet to allow immediate usage as a desk or
tabletop unit.

Rack Mounting

The ADA-205A unit can be mounted to EIA standard rack units. When rack mounting a unit,
remove the rubber feet and use the accessory rack mount brackets (rack ears).

Upon Receipt

Unpacking

ADA-205A unit and their accessories are fully inspected and adjusted prior to shipment.
Operation can be performed immediately upon completing all required connections and
operational settings.

Check your received items against the packing lists below.

ITEM QTY REMARKS

ADA-205A 1

AC Cord 1

Rack Mount Brackets 1 pr. EIA standard type

Operation Manual 1

Select the voltage range between 200 V or
100 V AC before purchasing

Check

Check to ensure no damage has occurred during shipment. If damage has occurred, or items
are missing, inform your supplier immediately.

IMPORTANT

To change the voltage range from 200 V to 100 V, or vice versa, after purchasing
products, consult your FOR-A reseller.

Components need to be replaced in the FOR-A factory.

Table of Contents

1. Prior to Starting ....................................................................................................... 1

1-1. Welcome .......................................................................................................... 1

1-2. About the ADA-205A ........................................................................................ 1

1-3. About This Manual ............................................................................................ 1

2. Panel Descriptions .................................................................................................. 2

2-1. Front Panel ....................................................................................................... 2

2-2. Rear Panel ....................................................................................................... 3

3. Setup and Connection ............................................................................................ 4

3-1. Stereo Audio Input ............................................................................................ 4

3-2. Monaural Audio Input ....................................................................................... 5

3-3. XLR Connector Pin Assignment ....................................................................... 6

4. Specifications and Dimensions ............................................................................... 7

4-1. Unit Specifications ............................................................................................ 7

5. External Dimensions ............................................................................................... 8

1. Prior to Starting

1-1. Welcome

Congratulations! By purchasing ADA-205A Audio Distribution Amplifier you have entered the
world of FOR-A and its many innovative products. Thank you for your patronage and we hope
you will turn to FOR-A products again and again to satisfy your video and audio needs.
FOR-A provides a wide range of products, from basic support units to complex system
controllers, which have been increasingly joined by products for computer video based systems.
Whatever your needs, talk to your FOR-A representative. We will do our best to be of continuing
service to you.

1-2. About the ADA-205A

The ADA-205A is a high performance balanced audio distribution amplifier capable of producing
up to five stereo outputs from one stereo input and up to ten monaural outputs from one
monaural input.

Features

 Front panel audio level control.

 Convenient audio output level indicator located on front panel.

 Compact and convenient EIA 1 RU size

1-3. About This Manual

This manual is intended to help the user easily operate the ADA-205A and make full use of its
functions during operations. Before connecting or operating your unit, read this operation
manual thoroughly to ensure you understand the product. After reading, it is important to keep
this manual in a safe place and available for reference.

1

2. Panel Descriptions

2-1. Front Panel

Indicators and switches located on the front panel of the ADA-205A are as shown and described
in the figure and text below.

ON

OFF

POWER

L CH LEVEL R CH LEVEL

OUTPUT

GAIN GAIN

LEVEL

①② ③ ④ ⑤ ⑥

Where:

① Power indicator

Power indicator will be lit green whenever power switch is set to ON and power applied to the
unit.

② Power switch

Used to turn unit power ON / OFF.

③ L CH LEVEL indicator

Used to show either left channel audio level during stereo operation or output (6, 7, 8, 9, 10)
audio level during monaural operation.

④ L CH LEVEL control

Used to adjust either left channel audio gain during stereo operation or output (6, 7, 8, 9, 10)
audio gain during monaural operation.

⑤ R CH LEVEL indicator

Used to show either right channel audio level during stereo operation or output (1, 2, 3, 4, 5)
audio level during monaural operation.

⑥ R CH LEVEL control

Used to adjust either right channel audio gain during stereo operation or output (1, 2, 3, 4, 5)
audio gain during monaural operation.

ADA-205A

AUDIO DISTRIBUTION AMPLIFIER

2

2-2. Rear Panel

Connectors and items located on the rear panel of the ADA-205A are as shown and described in
the figure and text below.

R-INPUT/MONO L-OUTP UT

R-OUTPUT L-INPUT

① ② ③ ④ ⑤ ⑨ ⑧

Where:

① R-INPUT/MONO

Used to input right channel stereo audio signals when MODE switch is set to STEREO or
monaural signals when MODE switch is set to MONO. XLR connector (female).

② R-OUTPUT

Used to output audio signals distributed from input connector ① above. Outputs either 5
right channel stereo signals or 5 monaural signals. XLR connectors (male).

③ MODE selection switch

Used to select either MONO/10-OUTPUT or STEREO distribution.
MONO setting distributes 10 monaural inputs from connector ① , STEREO setting
distributes 5 right channel stereo outputs from connector ① and 5 left channel stereo outputs
form connector ④.

④ L INPUT

Used to input left channel stereo audio signal when MODE switch is set to STEREO.

DO NOT connect this input when the MODE switch is set to MONO.

⑤ L-OUTPUT

Used to output audio signals distributed from input connector ① or ④ above. Outputs either
5 left channel stereo signals ④ or 5 monaural signals ① depending on MODE switch setting.

⑥ R/L INPUT 600Ω switch

Used to select either 600Ωtermination (ON) of R/L input or no termination (OFF).

⑦ FUSE holder

A fuse is installed.
100 / 117VAC 125V 0.3A (slow blow)
220 - 240VAC 250V 0.2A (slow blow)

⑧ Ground Terminal

Used to ground unit and protect operator from electrical shock.

⑨ AC IN

Used for connection to AC power source via supplied accessory cord.

⑥ ⑦



R/L INPUT 600

MONO
10-OUT

ONOFF

MODE

STEREO

1 51 2345

234

678910

0.3A

3

3. Setup and Connection

3-1. Stereo Audio Input

Setups of stereo audio input/output signal and connection example are as below.

1) Input right and left stereo channel signal to R-INPUT/MONO and L INPUT connectors,
respectively.

2) Set MODE selection switch to STEREO.

3) Stereo audio signal inputs are distributed to R-OUTPUT (1, 2, 3, 4, 5) and L-OUTPUT (1, 2,
3, 4, 5). Connect the output stereo audio signals to other audio equipment.

4) After all input and output connections are complete, turn unit power ON.

5) Adjust overall output levels using the L CH LEVEL and R CH LEVEL gain controls on the
front panel. (Factory gain setting is 0dB.)

 Connection Example

R-INPUT/MONO L-OUTPUT

R ch

R ch

CD

LINE OUT

L ch

MONO
10-OUT

R/L INPUT 600

MODE



ONOFF

STEREO

R-OUTPUT L-INPUT

L ch

LINE IN

CASSETTE

234

1 51 2345

678910

0.3A

L chR ch

AUX IN

AUDIO AMP.

4

3-2. Monaural Audio Input

Setups of monaural audio input/output signal and connection example are as below.

1) Input monaural audio signal to R-INPUT/MONO connector. (Do not input an audio signal to L
input.)

2) Set MODE selection switch to MONO/10-OUT.

3) Monaural audio signal input is distributed to R-OUTPUT (1, 2, 3, 4, 5) and L-OUTPUT (6, 7,
8, 9, 10). Connect the output monaural audio signals to other audio equipment.

4) After all input and output connections are complete, turn unit power ON.

5) Adjust overall output levels using the L CH LEVEL and R CH LEVEL gain controls on the
front panel. (Factory gain setting is 0dB.)

 Connection Example

R-INPUT/MONO L-OUTPU T

LINE IN

CASSETTE

CD

LINE OUT

R-OUTPUT L-INPUT

MONO
10-OUT

R/L INPUT 600

MODE



ONOFF

STEREO

AUX IN

AUDIO AMP.

234

1 51 2345

678910

0.3A

5

3-3. XLR Connector Pin Assignment

Connector appearance and pin assignments are as follows.

＜Input connector＞
XLR 3-pin (female)

Pin No. Signal

2 1

＜Output connector＞
XLR 3-pin (male)

1

3

3

2

2 HOT

3 COLD

1 SHIELD

Pin No. Signal

2 HOT

3 COLD

1 SHIELD

6

4. Specifications and Dimensions

4-1. Unit Specifications

Audio Input 0 dB (*1) Balanced 600Ω or 10kΩ (selectable)

Stereo L/R or Monaural x 1 (selectable), XLR 3-pin connector

Audio Output 0 dB (*1) ±0.5 dB within Balanced 600Ω

Stereo L/R x 5 or Monaural x 10 (selectable), XLR 3-pin connector

Max. I/O Level +18 dB

Gain Range Approx. ±8 dB (for input signal)

Frequency Response 20 Hz to 20 kHz: ±0.5 dB (1 kHz 0 dB base)

Distortion Less than 0.02% (at 1 kHz, 0 dB input)

S/N Ratio Better than 75 dB (at 1 kHz 0 dB input)

Temperature 0ºC to 40ºC

Humidity 30% to 90% (no condensation)

Power 100 V AC to 117 V AC or 220 V AC to 240 V AC ±10%, 50/60 Hz

(*2)

Consumption 12 VA (10 W) at 100 VAC, 11 VA (9 W) at 220 V AC

Dimensions 430 (W) x 44 (H) x 105 (D) mm

Weight 2 kg

(*1) 0dB=0.775V(rms)
(*2) To change the voltage range from 200 V to 100 V, or vice versa, after purchasing products,

consult your FOR-A reseller. Components need to be replaced in the FOR-A factory.

7

5. External Dimensions

0.3A

678910

1 51 2345

234

430

ON

OFF

POWER

L CH LEVEL R CH LEVEL

GAIN GAIN

39020

462

480

10-OUT

STEREO

MONO

MODE

ONOFF

R/L INPUT 600



OUTPUT
LEVEL

R-OUTPU T L-INPUT

ADA-205A

AUDIO DISTRIBUTION AMPLIFIER

Ø15

(20)

(All dimensions in mm.)

R-INPUT/ MON O L-OUTP UT

5
0
1

2

t

6

4

2

4

3

6
8

2x2-6.4x12

2
1

9
7

4
1

8

Warning

This equipment has been tested and found to comply with the limits for a
Class A digital device, pursuant to Part 15 of FCC Rules. These limits are
designed to provide reasonable protection against harmful interference
when the equipment is operated in a commercial environment. This
equipment generates, uses, and can radiate radio frequency energy and,
if 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 harmful interference, in
which case the user will be required to correct the interference at his own
expense.

01/06/2012 Printed in Japan

FOR-A COMPANY LIMITED

Head Office 3-8-1 Ebisu, Shibuya-ku, Tokyo 150-0013, Japan
Overseas Division Phone: [phone], Fax: [phone]
Japan Branch Offices Osaka/Okinawa/Fukuoka/Hiroshima/Nagoya/Sendai/Sapporo
R&D/Production Sakura Center/Sapporo Center

FOR-A America Corporate Office

11155 Knott Ave., Suite G&H, Cypress, CA 90630, USA
Phone: [phone] Fax: [phone]

FOR-A America East Coast Office

2 Executive Drive, Suite 670, Fort Lee Executive Park, Fort Lee, NJ 07024, USA
Phone: [phone] Fax : [phone]

FOR-A America Distribution & Service Center

2400 N.E. Waldo Road, Gainesville, FL 32609, USA
Phone: [phone] Fax: [phone]

FOR-A Corporation of Canada

346A Queen Street West, Toronto, Ontario M5V 2A2, Canada
Phone: [phone] Fax: [phone]

FOR-A Latin America & the Caribbean

5200 Blue Lagoon Drive, Suite 760, Miami, FL 33126, USA
Phone: [phone] Fax: [phone]

FOR-A UK Limited

UNIT C71, Barwell Business Park, Leatherhead Road, Chessington Surrey, KT9 2NY, UK
Phone: [phone] Fax: [phone]

FOR-A Italia S.r.l.

Via Volturno 37, 20047 Brugherio MB, Italy
Phone: [phone] Fax: [phone]

FOR-A Corporation of Korea

1007, 57-5,Yangsan-ro,Yeongdeungpo-gu, Seoul 150-103, Korea
Phone: [phone] Fax: [phone]

FOR-A China Limited

708B Huateng Bldg., No. 302, 3 District, Jinsong, Chaoyang, Beijing 100021, China
Phone: [phone] Fax: [phone]

FOR-A Middle East-Africa Office

Jebel Ali Free Zone, LOB-16, Office 619, P. O. Box: 261914 Dubai, UAE
Phone: [phone] Fax: [phone]

*The contents of this manual are subject to change without notice.