AP20 Installation and Operating Guide
Page 37
AP20 Installation & Operating Guide
Document # 9301H39200 Ver. 1.1
2.9.1
Set levels to establish a baseline
In the auditorium, confirm that all amplifiers are ON, mute is OFF, and masking and
curtains are opened.
Use a high-quality, calibrated SPL meter in the auditorium.
Menu > Format > Channel Profile > Analog Output Levels
Set the Fader to 7.0. That’s the standard reference level.
Run Pink Noise on each channel, one by one.
First, by adjusting the amplifiers, try to achieve the baseline levels. Set the SPL levels
according to the chart below.
Note that SPL readings for screen and surroundings should be measured un-weighted, or C-
weighted, with the meter set to slow.
Use an RTA to calibrate the proper level setting of the subwoofer.
Table 10: SPL levels
Channel Description
SPL
1
Left
85 dB
2
Right
85 dB
3
Center
85 dB
4
Sub bass
91 dB*
5
Left Surround
82 dB
6
Right Surround
82 dB
7
Back Surround
82 dB
8
Left Center
85 dB
9
Right Center
85 dB
* Subwoofer should be set to 10 dB of in-band gain
(see SMPTE RP-200), which equates to approximately 91 dBC (slow).
If not possible to achieve the baseline, use the AP20 (Analog Output Levels) to make minor
adjustments.
