Getting The Most From Your Subwoofer
11
4) Play Track 1 and adjust volume and your meter
settings to a suitable level and record this value in the
table provided - this is your reference value.
5) Play tracks 2-11 on the CD in turn. Sitting in the
listening position, record in the table the reading
shown on your meter for each track.
6) If any of the readings are greater than 2dB higher than
the reference value then proceed as follows -
a) Switch the notch filter ON and ensure that the Cut
control is set to its minimum value of 2dB.
b) Repeat the track that shows the highest SPL meter reading.
c) Adjust the frequency control of the notch filter until
the reading on the SPL meter reaches its lowest
value. Remember to leave the SPL meter in your
listening position - this may require an assistant.
d) If this is still not enough to reduce the peak to the
level of the reference value, increase the cut
control - a maximum of 16dB of cut is available.
7) Repeat step 5 to confirm the problem frequency has
been satisfactorily reduced. If it hasn't then repeat step 6.
8) If there is more than one peak that registers more
than 2 dB above the reference value, always pick the
larger peak. If more than one peak is present with the
same value (e.g. 2 peaks of 4dB) then experiment
with notching out each peak in turn - one will have a
more noticeable effect when the whole system is
playing music.
Test
Tone
Freq
(Hz)
SPL Meter
Readings
1
2
3
4
5
6
7
8
9
10
Ref.
25-27
27-29
29-32
32-36
36-42
42-48
48-57
57-71
71-92
92-11011
