Infinity Modulus MSW-1, Service Manual

MSW-1

12

TEST SETUP and PROCEDURE

SIGNAL

GENERATOR

AMPLIFIER

AC VOLT

METER (10V)

MODULUS MSW-1

UNDER TEST

OUTPUT

FROM

GENERATOR/AMPLIFIER

In

®

®

O

00539

SYSTEM AURAL SWEEP TEST
Equipment needed:
•

Function/signal generator/sweep generator

•

Integrated Amplifier

•

Multimeter

•

Speaker cables

General Unit Function (UUT = Unit Under Test)
Switches/knobs on the amplifier faceplate:
Input Select to "Line"
Low Pass Filter switch to OFF
Bass Optimization switch to OFF
Phase switch - either position

1.

From the signal generator, Connect both right and left line level inputs (RCA) to signal generator and UUT. Use Y-
cable if necessary from mono source.

2.

On the front of the unit, turn the LEVEL control full clockwise (0).

3.

Turn on generator, adjust to 120mV, 30 Hz.

4.

Plug in UUT; turn the power switch ON. LED should be Red. Turn LEVEL control full counterclockwise (10)

5.

LED should now be Green; immediate bass response should be heard and felt from bottom port tube opening.

6.

Turn off generator, turn LEVEL control fully clockwise (0), disconnect RCA cable.

7.  Connect one pair of speaker cables to Speaker Level input terminal on UUT. Cables should be connected to an

integrated amplifier fed by the signal generator.

8.

Change Input selector switch to "Speaker".

9.

Turn on generator and adjust so that speaker level input at the amplifier is 2.2V, 30 Hz.

10. Turn LEVEL control full counterclockwise (10)
11. Green LED should light, immediate bass response should be heard and felt from the port tube opening.

Sweep Function
1.

Follow steps 7-10 above, using a sweep generator as a signal source.

2.

Sweep generator from 20Hz to 1kHz. 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 (Woofer)
1.

Remove woofer from cabinet; and - wire clips. See page 9 for removal instructions.

2.

Check DC resistance of woofer; it should be 3.4 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.