1. Select a new test position: Cue the test track corresponding toAlthough it looks as though this system is quite bass-deficient,
the center frequency of the dip. In the first example in Figure 18,this is actually indicative of a single, very narrow peak in excess
you would play Track 13 (56Hz). Press Play? .You will see aof 10dB high.
reading very close to what you had before. Now, slowly move the
RSLM around the area, if possible remaining within about a footApply the Width Selector as described above.Align the center-line
of the original test point.As you move the RSLM, watch the barof the Selector over the center of the peak, as shown in Figure
graph.You will observe large level fluctuations. Find a position13. Now adjust the Selector until you have achieved the Obest fit.�
that restores the level to approximately that of the adjacent testThe slider now points to the correct width setting. In this
points.You may find it helpful to move the RSLM vertically. Dipsexample, the frequency is 40Hz and the best-fit width is 10%. Fill
can be oriented in any axis.The position that restores the level toin the Width and Frequency fields provided on the template.
about that of the adjacent test points is your new test position.
Determine the appropriate level using the technique described
2. Reset the test level: Return to the section OSetting theearlier. In this example, �13dB is indicated. Enter 13 in the field
Subwoofer Test Level�on page 7. Perform the procedure provided.
as described.
Skip to the OAdjusting the R.A.B.O.S.Equalizer�section on page 14.
3. Repeat the measurements: Now that you are familiar with the
measurement process, you can go much faster by using TracksExample 5. One or More Narrow Dips:
27�50.These tracks contain all the test tones necessary for
measurement. However, each test is only about three seconds, and
there is no frequency announcement.The first test is 100Hz. Just
place each test mark in order until finished. Connect the dots.
Your second measurement will no longer exhibit the deep
response dip. However, the peak will still be evident.Without the
influence of the response dip, the amplitude and center of the
peak may have changed. Compare your new data to the examples
given in this section of the manual. Follow the instructions for the
example that most closely matches your new measurement.
Example 4. Narrow Response:
Figure 19.Example of two narrow dips
Response dips can occur at any frequency, sometimes
immediately adjacent to the peak you want to correct. In this
example, there are two such dips on either side of the peak. Deep
response dips such as these are caused by destructive wave
interference. Destructive interference dips occur only in one spot
within the room. It is not uncommon to completely eliminate their
effect by moving the RSLM to a different location. Note that this
does not eliminate the dips.We have simply moved away from
them. Sometimes only a few inches are required. Do not attempt
to correct this condition with equalization. If you encounter dips
like this, take the following steps:
Figure 18.Narrow Response
13CSW-10 |
ACEC
