Mordaunt-Short MS909W - Manual (Page 11)

Getting The Most From Your Subwoofer
11
4) Play each track on the CD in turn. Sitting in the
listening position and using the table provided, record
the reading shown on your SPL meter for each tone.
5) If any of the readings show a peak of more than 6dB
in a particular frequency range then:
a) Switch the notch filter ON
b) Repeat the track for that particular frequency
c) Turn the 'cut' control to -6dB
d) Turn the 'frequency' control until the SPL Meter
reads 6dB lower than its previous reading
(remember to take the SPL reading from the
same position - this may require an assistant).
6) Repeat step four to confirm the problem frequency
has been satisfactorily reduced. If it hasn't then repeat
step five. If more than 6dB of cut is required then up
to 18dB is available.
Test
Tone
Freq
(Hz) SPL M Meter
Readings
1
2
3
4
5
6
7
8
9
10
12
13
14
15
16
17
19
21
24
27
30
34
38
42
47
53
60
67
75
84
11
95