JBL Arc Sub 8 Manual

SERVICE MANUAL
JBL Consumer Products Inc.
250 Crossways Park Drive
Woodbury, N.Y. 11797
A Harman International Company
1112-ARCSUB8 Rev A 10/98
SERVICE MANUAL
ARC SUB 8
Discrete Output, High Current
8 Powered Subwoofer 

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Powered SubwooferARC SUB 8
TABLE OF CONTENTS
SPECIFICATIONS..........................................................1
WARRANTY ...................................................................2
SAFETY SYMBOLS .......................................................2
CONTROLS AND THEIR FUNCTION ...........................3
TEST PROCEDURES ....................................................4
TROUBLESHOOTING ...................................................5
ARC SUB 8 AMPLIFIER BLOCK DIAGRAM...

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Powered SubwooferARC SUB 8
WARRANTY
This amplifier is warranted against defects in material and
workmanship for a period of 90 days from date of shipment,
when installed in accordance with the owner’s manual in a
clean, dry, interior home environment. THIS AMPLIFIER IS
NOT SUITABLE FOR OPERATION OUTSIDE OR IN HARSH
ENVIRONMENTS. During the warranty period, the
manufacturer will, at its option, either repair of replace products
which prove to be defective.
For warranty service or repair, this product...

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Powered SubwooferARC SUB 8
CONTROLS AND THEIR FUNCTION
1.Output Level- The Output Level adjustment
determines volume level strength.
2.Crossover Frequency- The Crossover Frequency
adjustment determines the highest frequency the
ARC SUB 8 will reproduce. It allows a seamless
transition from the subwoofer to the satellite
speakers.
3.On (LED)- This LED will light green when the unit is
plugged in and is receiving signal. When in
standby mode the LED is red.4.Low Level Input- These left and right Line...

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Powered SubwooferARC SUB 8
TEST PROCEDURES
General Function
UUT = Unit Under Test
1. Connect both right and left line level inputs (RCA) to signal generator and UUT. Use Y-cable if necessary from
mono source. VOLUME control should be full counterclockwise.
2. Turn on generator, adjust to50mV, 50 Hz.
3. Plug in UUT; red LED should be ON. Turn VOLUME control full clockwise.
4. LED should turn Green; immediate bass response should be heard and felt from port tube opening.
5. Turn off generator, turn...

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Powered SubwooferARC SUB 8
1. TROUBLE SHOOTING BEFORE OPENING
Check connections, control settings, driver and other possible
external problems. If there is Output, determine if all controls
and Inputs function properly. Rotate Pots over full range while
applying lateral and vertical oscillating forces to locate possible
intermittent function. High Level Inputs should be tested
individually both differentially (signal from - to + with normal
output) and in common mode (signal from low level ground to...

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Powered SubwooferARC SUB 8
H.If signal present at pin 8, but still no sound, check
for cold solder joints on all power resistors, R4a and
R4b and the the power amp module. If C24 is
blown, C6 is not soldered or is defective. Check the
signal at R2. On the down signal side, the voltage
signal should be very small. If signal is similar on
both sides of R2, the amp module is likely defective.
I.If you hear a mechanical clicking noise from the amp
module, this indicates that the short circuit protection...

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Powered SubwooferARC SUB 8
ARC SUB 8 AMPLIFIER BLOCK DIAGRAM 

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Powered SubwooferARC SUB 8
CABINET EXPLODED VIEW 

Ref # Part # Description Qty.
Capacitors
C1, 2 30701 3300mF 50V +/-20% 2
ELECTROLYTIC RADIAL
C3 30501 .1mF 50V +/-20% 1
MONO-CERAMIC AXIAL
C4, 5, 9, 17, 24 30502 .1mF 50V +/-20% BIPOLAR 5
MONO-CERAMIC
C6 30705 10mF 50V +/-20% BIPOLAR 1
ELECTROLYTIC RADIAL
C7, 25 30503 .0022mF 50V +/-10% 2
MONO-CERAMIC
C7A, 7B 30505 .1mF 100V +/-20% 2
METAL POLYESTER RADIAL
C8, 10, 14, 18, 30504 .1mF 50V +/-10% 6
19, 20 MONO-CERAMIC
C11 30702 100mF 35V +/-20% 1
ELECTROLYTIC RADIAL
C12 30703 4.7mF 35V +/-20% 1
ELECTROLYTIC...