NOTE: To distinguish between normal suspension noise and rubs or ticks, displace the
cone on the woofer slightly with your fingers. If the noise can be made to go away or get
worse, it is a rub or a tick and the woofer should be replaced. If the noise stays the same, it
is normal suspension noise and the woofer is fine. Suspension noises will not be heard with
program material.
2. Woofer Sweep Test
A. Sweep the oscillator from 10 Hz to 3 kHz using the 8 Vrms signal. There should not be
any loud extraneous sounds. If there are any loud buzzes or distortion, replace the woofer.
NOTE: There should not be any buzzes or rattles from within the speaker cabinet. Redress
any wire or component that buzzes.
3. Tweeter Sweep Test
A. Reduce the amplifier output to 4.0 Vrms and continue sweeping from 3 kHz to 15 kHz.
If one of the tweeters is buzzing or distorting, replace it.
4. Air Leak Test
A. Using the 8 Vrms signal, set the oscillator frequency to 45 Hz. For at least 5 seconds,
listen for air leaks around the woofer,terminal cup and tweeter mounting brackets. If there is
a "whooshing" noise around the woofer, re-position the woofer gasket behind the woofer to
make an airtight seal. If there are any similar noises around either of the tweeter mounting
brackets or the terminal cup, make sure that these items are securely fastened to the
speaker assembly.
2
Test Connections 301 III Speaker
+
-
Audio Signal
Generator
Power Amplifier
Input
Output
Speaker
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-
+
+
-
+
FIGURE 1