Adjusting the R.A.B.O.S. Equalizer

1.Select a new test position: Cue the test track corresponding to the center frequency of the dip. In the example in Figure 29 you would play Tracks 14 (52Hz) and 18 (40Hz). Press Play ›. You will see a reading very close to what you had before. Now, slowly move the RSLM around the area, if possible remaining within about a foot of the original test point. As you move the RSLM, watch the bar graph. You will observe large level fluctuations. Find a location for the subwoofer or a test location that raises the response at these frequencies. You may find it helpful to move the RSLM vertically. Dips can be oriented in any axis. The position that restores the level to about that of the adjacent test points is your new test position.

2.Reset the test level: Return to the section “Setting the Subwoofer Test Level”on page 11. Perform the procedure as described.

3.Repeat the measurements: Now that you are familiar with the measurement process, you can go much faster by using Tracks 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 dips. However, the peak will still be evident. Without the influence of the response dips, the amplitude and center of the peak may have changed.

4.Interpret the new data: 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 6. Ideal Response:

Ideal response, no EQ needed

FIGURE 30

If your test data looks similar to the example in Figure 30, you have a very favorable setup. Skip to the “Final System Balance” section, page 19.

Now that you have performed the measurements and interpreted the data, you have the information needed to adjust the subwoofer’s equalizer.

There is a R.A.B.O.S. On/Off Switch ¡ located in the top right corner of the Modulus subwoofer’s rear. This switch must be set to the “On” position in order for the equalizer controls to take effect. You can defeat all equalizer controls by setting the switch to the “Off” position.

There are three equalizer adjustments on the Modulus II subwoofer. Top to bottom, they are marked “Freq,” “Width” and “Level.” Each control has 21 positions. These are numbered from left to right. Therefore, Position 1 is the full counter- clockwise position.

R.A.B.O.S.™ Freq.

Controls

Width

Level

The table below illustrates all switch positions.

Position	F (Hz)	L (dB)	W

1 CCW	20	–14.1	4.5%
2	20	–13.9	5%
3	20	–13.5	7.5%
4	21	–13.1	10%
5	22	–12.7	12.5%
6	24	–11.7	16.5%
7	26	–11.0	20.5%
8	30	–10.2	23%
9	35	–9.5	26%
10	38	–8.9	28%
11	40	–8.3	29.5%
12	43	–7.9	31%
13	46	–6.4	34%
14	49	–4.4	39%
15	52	–2.9	41.5%
16	56	–1.9	43.5%
17	63	–1.1	45%
18	66	–0.5	46.5%
19	72	0.0	48%
20	77	0.0	49%
21 CW	80	0.0	49.5%

Harman-Kardon II manual Adjusting the R.A.B.O.S. Equalizer