Datasat AP20 Installation And Operating Manual page 136

AP20 Installation and Operating Guide
Parametric Filter Setting
The frequency (Freq) select button is used to scroll and select the desired frequency. Press the button and
turn the fader to make the selection.
The Q button is used to select the bandwidth range when making an EQ adjustment. A smaller number
adjusts frequencies closest to the Freq selected whereas a large number will expand the adjustment affect.
Press the button and turn the main fader to make selection.
The Gain button is used to make level adjustments at the filter frequency. Press the gain button and turn
the main fader as needed.
F4.4.6. (OBE) Optical Bass Extension
Items needed: Pink Noise test film (CAT 69P), RTA with Microphone
When Optical Bass Extension is selected, the right half of the screen provides settings for the parameters of
optical bass gain and low pass filter frequency (see Figure 19 below).
Menu (System) → Formats → Format Options → Film Options → Film Setup → Optical Bass
Extension
Figure 19 – Optical Bass Extension
Optical Bass Gain allows you to set the gain for the optical bass. Press the button with the number
displayed and rotate the main fader to adjust for the desired level.
Low Pass Filter allows you to choose the frequency of the filter. Press the button with the number
displayed and rotate the main fader to adjust the desired frequency.
When adjusting the Optical Bass Extension, set up a microphone in the auditorium. It is best to use a single
microphone, or if using a multiplexer select single microphone only, and connect it to the RTA.
Thread (Pink noise) Cat 69P test film into the projector. Turn off all amplifiers except the Center channel.
Select an optical format on the AP20, start the projector and note the level and low frequency roll off
displayed on the RTA. Select the appropriate Low Pass Filter setting by pressing that button and using the
fader knob to make any changes required to match the low pass filter to the roll off measured.
Next turn on the subwoofer channel, then select the Optical Bass Gain by pressing the <Gain> button. Use
the AP20 fader knob, or up and down keys when using a laptop, to adjust the Optical Bass Gain to match
the Center channel level previously noted on the RTA display. The Optical Bass Gain range is 0 to
+10dBc. Don't forget to turn on all amplifiers when adjustment is complete.
Appendix F. H338 Optical Film Card Option F-15
Version 1.2
Document #: 9301H39200 1.2