Datasat AP20 Installation And Operating Manual page 25

4. Examine the response on the RTA (whichever RTA the microphone is attached to).
5. Turn on XCurve Display. Try to tune the frequency pattern to the XCurve. If the pattern does
not conform – there is a hole or a peak or other variance – then select the frequency that needs
adjusting, and push it down or pull it up.
6. Select a frequency in the lower panel by touching the yellow bar for the specific frequency.
7. Use the adjustment knob to adjust the frequency up or down.
8. Repeat the above for each channel except the subwoofer (LFE).
2.9.2.1 A note about XCurve
XCurve is the roll-off; it is how theaters are supposed to be tuned. The XCurve is flat all the
way out to 2K, and then there is a 3dB roll-off per octave. The Third Octave EQ screen offers
three ways to look at the XCurve. XCurve is appropriate for both film playback and digital
cinema.
XCurve Off is just the natural display that gives you a flat response.

XCurve Offset adds the 3dB per octave roll off starting at 2K. When in this mode you

should adjust the response flat.
XCurve Display (shown below) shows the guidelines. The two narrow lines are the plus

and minus range of 3dB that is allowable. The heavier center line is the optimal level.
The scale (y-axis) on the left edge of the RTA is adjustable. Touch the scale and it will cycle
through several different scales. You can also adjust the scale by touching the RTA Options
button, which displays a control dialog.
Menu > Formats > EQ Setup > Third Octave EQ > XCurve Display
Figure 18. XCurve Display at +/- 6dB Scale
AP20 Installation & Operating Guide
AP20 Installation and Operating Guide
Document # 9301H39200 Ver. 1.1
Page 39