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TEST PROCEDURES
2. Woofer Phase Test
2.1 Momentarily apply a positive 5 volt DC
level to the 1+ and 1- terminals of one of the
Neutrik NL4 connectors.
2.2 While applying the DC level, ensure that
the woofers move outward, away from the
cabinet. If they move inward, remove the
driver and correct the wiring connections.
3. Woofer Rub and Tick Test
Test Signal: Shaped Sine Wave Sweep
10-1khz with 400 Hz 2nd order Butterworth
LP, 600 Hz first order Butterworth LP filters.
3.1 Remove the bass grilles using disas-
sembly procedure 2.
3.2 Apply a 20Vrms, test signal to the 1+ and
1- terminals of one of the Neutrik NL4 con-
nectors.
3.3 Listen to the woofers for any rubbing,
ticking or other extraneous noise. Replace
any defective woofer. Small ticks are accept-
able if they cannot be heard at a distance of
one foot.
Note: There is a normal suspension noise.
To distinguish between a rub or a tick and
suspension noise, displace the cone slightly
with your finger. If the rubbing can be made
to go away or get worse, it is a rub or a tick.
If the noise stays the same, it is suspension
noise.
4. System High Frequency Sweep Test
CAUTION: Hearing protection is required to
prevent potential hearing loss duing this test.
Test Signal: Shaped Sine Wave Sweep
300-2khz with 300 Hz 1st order Butterworth
LP, 900 Hz second order Butterworth LP
filters.
4.1 Apply a 20Vrms (maximum), test signal
to the 2+ and 2- terminals of one of the
Neutrik NL4 connectors.
4.2 Sweep the loudspeaker from 50Hz to
16kHz. Listen to the drivers for any rubbing,
ticking or other extraneous noise. Replace
any defective driver. Small ticks are accept-
able if they cannot be heard at a distance of
one foot.
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