User`s manual

B-Chain Alignment Procedures
Notes
5-3
5.2 Setting Room Equalization
5.2 Room Equalization
Equalization is performed using the real-time analyzer and a calibrated
microphone(s). The adjustment for the full range channels involves setting 7-
band equalizer controls for each of the screen channels (left, center, and right),
and a 3 band equalizer for the surround channel(s). The ideal setting is reached
when the room response readings on the RTA match the standard curves shown
in this manual.
The Left, Center, and Right channel response should extend smoothly from 40
or 50 Hz to significantly beyond 10kHz, and ideally as far as 16kHz. The level
difference between any two locations in the normal seating area of the theater,
measured in 1/3 octaves from 150Hz to 10kHz, should not exceed 3 dB.
Set all the gain controls on all power amplifiers to a known repeatable setting,
but do not turn amplifiers on. The preferred setting for the amplifier gain
controls is maximum. If a different setting is required in order to optimize the
noise performance of the system, the controls should be locked in position or
marked clearly.
Position calibrated microphones in the theatre. Whenever possible use multiple
microphones and a multiplexer.
For a single microphone the recommended position is shown in the diagram —
2/3 of the way from the front speakers to the rear — but off the axis of the center
speaker — 5 feet off the floor level — and angled 45 degrees upward toward the
screen. Connect the microphone to the RTA.
Set the front panel NORMAL/BYPASS switch on the CP45 BYPASS.
Turn power ON to the power amplifiers.