Test Set Up And Procedure; Equipment Needed; Initial Control Settings; General Unit Function (Uut = Unit Under Test) - JBL Cinema Sound CSS10 Service Manual

CSS10

Equipment needed:

• Function/signal generator/sweep generator
• Integrated Amplifier
• Multimeter
• Speaker cables

Initial Control Settings:

• Power Switch OFF
• Level MIN (Full CCW)
• Phase, Auto/On switches do not matter

General Unit Function (UUT = Unit Under Test)

1) From the signal generator, connect one line level (RCA) cable to the Subwoofer Line Level In jacks L/R on
the UUT. Use a Y-cable from a mono source if necessary to connect to both inputs. Do not connect to the
single, purple LFE input.
2) Turn on generator; adjust to 75mV, 50 Hz.
3) Plug in UUT; turn the power switch ON. Turn LEVEL control full clockwise (MAX)
4) LED should turn from Red to Green; immediate and vigorous bass response should be heard and felt from
port tube opening.
5) Turn off generator, turn LEVEL control full counterclockwise (MIN), and disconnect RCA cable.
Sweep Function
1) Follow steps 1-5 above, using a sweep generator as a signal source.
2) Sweep generator from 20Hz to 300Hz. Listen to the cabinet and drivers for any rattles, clicks, buzzes or
any other noises. If any unusual noises are heard, remove woofer and test.
Driver Function
1) Remove woofer from cabinet; detach + and - wire clips.
2) Check DC resistance of woofer; it should be 3.5 ohms ±10%
3) Connect a pair of speaker cables to driver terminals. Cables should be connected to an integrated amplifier
fed by a signal generator. Turn on generator and adjust so that speaker level output is 5.0V.
4) Sweep generator from 20Hz to 1kHz. Listen to driver for any rubbing, buzzing, or other unusual noises.
5) Caution: Observe correct polarity when re-attaching speaker wires as terminals are identical in size..

Test Set Up and Procedure

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Cinema Sound