Atlas IED AF140 Data Sheet

AF140

4.125"

140 Watt Autoformer

Specications

Frequency Response 30Hz – 15kHz (±1dB)

Insertion Loss .3dB

Terminations 6" (152mm) Color Coded Leads

3

Core Size 1

Power Rating 140 Watts

Weight 6.25 lbs (2.8kg)

⁄8" Square (35mm)

3.4375"

(87mm)

1.375"

(35mm)

AF140

Features

• Serves as a Method for Matching Loudspeaker Loads to Amplifier
Outputs

• Suitable for Professional and Commercial Sound Applications

General Description

Model AF140 consists of a single coil autoformer with multiple taps for

maximum flexibility in match ing a wide variety of loud speak er loads to

power amplifier outputs. A single AF140 will handle loads up to 150 Watts

and by connecting two units in series, power handling capacity can be

increased to 300 Watts.

Green

5

Yellow

4

+

Com

3

2

1

Brown

Red

Black

2.75"

(70mm)

2.375"

(60mm)

Architect & Engineer Specications

Auto transformer shall be Atlas Sound Model AF140 or approved equal. It

shall be capable of handling 140 Watts of audio power with a frequency

response of 30Hz – 15kHz (±1dB).

1

Dimensions shall be 4

shall be via color-coded wire leads.

⁄8" H x 37⁄16" W x 13⁄8" D. External con nec tions

Note: The wire colors are for

©2011 Atlas Sound L.P. All rights reserved. Atlas Sound and Strategy Series are trademarks of Atlas Sound L.P. All other trademarks are the property of their respective owners. ATS0 04034 RevA 7/11

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TELEPHONE: [phone]
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identification purposes only.

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1 Black

2 Red

3 Brown

4 Yellow

5 Green

Amplifier Rating:

50 - 80 Watts

70.7V Line

+

Common

8Ω

+

Common

1 Black

2 Red

3 Brown

4 Yellow

5 Green

Amplifier Rating:

85 - 100 Watts

8Ω

+

Common

1 Black

2 Red

3 Brown

4 Yellow

5 Green

Amplifier Rating:

115 - 150 Watts

++

Common

8Ω

Common

70.7V Line

Amplifier Rating:

(70.7V Line)

Input

(8Ω)

Output

(70.7V Line)

1 Black

2 Red

3 Brown

4 Yellow

5 Green

1 Green

2 Yellow

3 Brown

4 Red

5 Black

Amplifier Rating:

200 - 260 Watts

N.C. N.C. N.C. N.C.

“A” “B”

1 Green

2 Yellow

3 Brown

4 Red

N.C. N.C. N.C. N.C.

“A” “B”

2 Red

3 Brown

4 Yellow

5 Green

+

Common

70.7V Line

1 Black

2 Red

3 Brown

4 Yellow

5 Green

Amplifier Rating:

50 - 80 Watts

70.7V Line

+

Common

8Ω

+

Common

1 Black

2 Red

3 Brown

4 Yellow

5 Green

Amplifier Rating:

85 - 100 Watts

70.7V Line

+

Common

8Ω

+

Common

(70.7V Line)

Amplifier Rating:

1 Black

2 Red

3 Brown

4 Yellow

5 Green

Amplifier Rating:

115 - 150 Watts

++

Common

8Ω

Common

70.7V Line

70.7V Line

+

Common

(70.7V Line)

Input

(8Ω)

Output

(70.7V Line)

Amplifier Rating:

1 Green

2 Yellow

3 Brown

4 Red

5 Black

1 Black

2 Red

3 Brown

4 Yellow

5 Green

Amplifier Rating:

270 - 300 Watts

N.C. N.C. N.C. N.C.

“A” “B”

1 Black

2 Red

3 Brown

4 Yellow

5 Green

Amplifier Rating:

115 - 150 Watts

++

Common

8Ω

Common

70.7V Line

5 Green

70.7V Line

+

Common

1 Black

2 Red

3 Brown

4 Yellow

5 Green

Amplifier Rating:

85 - 100 Watts

70.7V Line

+

Common

8Ω

+

Common

1 Black

2 Red

3 Brown

4 Yellow

5 Green

Amplifier Rating:

115 - 150 Watts

8Ω

Common

1 Black

2 Red

3 Brown

4 Yellow

5 Green

Amplifier Rating:

85 - 100 Watts

70.7V Line

+

Common

8Ω

+

Common

Using the AF140 Autoformer to Convert 8Ω Output to 70.7V Lines

Step 1: Determine the wattage rating of the amplifier.

Step 2: Locate the diagram below that most closely matches the rating of your amplifier and follow the connections shown.

8Ω

Common

8Ω

Common

Amplifier Rating:

30 - 45 Watts

1 Black

2 Red

3 Brown

4 Yellow

5 Green

70.7V Line

8Ω

+

+

Common

+

Common

Amplifier Rating:

85 - 100 Watts

1 Black

2 Red

3 Brown

4 Yellow

5 Green

70.7V Line

8Ω

+

Amplifier Rating:

50 - 80 Watts

1 Black

2 Red

3 Brown

4 Yellow

Amplifier Rating:

115 - 150 Watts

1 Black

2 Red

3 Brown

4 Yellow

5 Green

70.7V Line

+

Common

5 Green

70.7V Line

++

+

Common

Common

Common

©2011 Atlas Sound L.P. All rights reserved. Atlas Sound and Strategy Series are trademarks of Atlas Sound L.P. All other trademarks are the property of their respective owners. ATS0 04034 RevA 7/11

“A” “B”

1 Green

2 Yellow

3 Brown

N.C. N.C.

160 - 190 Watts

4 Red

5 Black

Input

(8Ω)

Output

1 Black

2 Red

3 Brown

4 Yellow

5 Green

N.C. N.C.

270 - 300 Watts

“A” “B”

1 Green

2 Yellow

3 Brown

N.C. N.C. N.C. N.C.

4 Red

5 Black

Input

(8Ω)

Output

1 Black

200 - 260 Watts

“A” “B”

1 Black

2 Red

3 Brown

4 Yellow

5 Green

N.C. N.C. N.C. N.C.

Input

(8Ω)

Output

2 Red

3 Brown

4 Yellow

5 Green

1 Green

2 Yellow

3 Brown

4 Red

5 Black

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Using the AF140 Autoformer

The AF140 autoformer can be used to solve a wide variety of impedance-

matching and voltage step-up/step-down problems. The key to under-

standing how to best utilize the AF140 depends upon being able to

convert both the input and output to the same unit of measure. In other

words, you must know the input voltage in order to determine the output

voltage. Likewise, the input impedance must be known to find the output

impedance. Both of these values can be determined by using simple

Ohm’s Law formulas and the reference chart.

Simply follow these steps:

Step 1: Convert the input and output to the same unit of measure using

the formulas on the circle chart.

Step 2: Calculate the ratio between the input and the desired output

(accomplished by dividing the output by the input).

Example: Converting 100 Watt, 8Ω Amplifier Output to a 70.7V Line

OUTPUT
INPUT

• 70.7 Volts

28.3 Volts

Example: Matching Six 16Ω Loudspeakers Connected in Parallel to an

8Ω Amplifier Output

• 2.66Ω

8Ω

= 2.5 Voltage Ratio

= .332 Impedance Ratio

= RATIO

Step 3: Find the desired ratio (voltage or impedance) on the step-up or

step-down charts on pages 4 and 5 and use the input and output

connections indicated. (If the exact ratio needed is not shown on

the chart, use the closest one available.)

The exact output can be determined by multiplying the input by the ratio

shown on the chart.

Note: the “common” will be shared by both the input and output.

Also, don’t be confused by the color of the wires. They have no

meaning other than to distinguish one from another. The black

wire will not be “common” in every case.

A single AF140 will handle loads up to approximately 150 watts. For

applications requiring more power, two AF140s can be connected in

series.

The diagrams and charts on pages 6 and 7 show the connections and all

the possible step-up and step-down ratios.

One of the more common applications of the AF140 is converting 8Ω

amplifiers to “70V” lines. The handy reference guide on page 2 shows

connections for amplifiers from 30 watts to 300 watts.

©2011 Atlas Sound L.P. All rights reserved. Atlas Sound and Strategy Series are trademarks of Atlas Sound L.P. All other trademarks are the property of their respective owners. ATS0 04034 RevA 7/11

1601 JACK MCKAY BLVD. ENNIS, TEXAS 75119 U.S.A.
TELEPHONE: [phone]
FAX [phone]

AtlasSound.com

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