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Disconnect all loudspeakers from the subwoofer outputs.
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Select the loudspeaker to be used as the reference for the phase alignment. Typically, this is the
Front Center loudspeaker in a 5.1 multi-channel system.
•
Connect this loudspeaker to subwoofer’s AES/EBU OUTPUT 1 connector.
•
Select subframe A for reproduction on the reference loudspeaker.
•
The test tone is played simultaneously from the subwoofer and loudspeaker.
•
Listen to the tone and adjust both “PHASE” control switches to find the setting that gives the
minimum tone level at the listening position.
•
After having found this minimum level setting, set the “-180 DEG” switch to the opposite setting to
complete the setup. This puts the subwoofer in phase with the reference loudspeaker and
completes the phase calibration.
•
Finally, reconnect all loudspeakers to the subwoofer outputs.
In a system with multiple daisy-chained subwoofers, the Phase and Bass Roll-Off adjustments should be
performed individually for each subwoofer in the system.
•
Set the “MODE” switch on all subwoofers to the ”NORMAL” position and disconnect the cables
from the outputs of all the subwoofers.
•
Follow the phase alignment process detailed above by connecting the reference loudspeaker to
each subwoofer in turn and adjust the “PHASE” control switches.
•
Finally, set the “MODE” switches on all subwoofers to a setting appropriate for their position in the
daisy-chain - all subwoofers set to “PASS THROUGH” mode except the last which is set to
“NORMAL”.
Subwoofer level
The level of the subwoofer relative to the loudspeakers can be adjusted with the “SUBWOOFER LEVEL”
rotary control. This control allows matching the subwoofer level to the levels of the other loudspeakers.
When two subwoofers are daisy-chained together in the same system, the in-room sound pressure
level increases by 6 dB, three subwoofers gives an increase of 9.5 dB and four subwoofers gives an
increase of 1 dB compared to a single subwoofer. To compensate for this increase in bass level, adjust
“SUBWOOFER LEVEL” in all the subwoofers in the daisy-chain to the same level to match the sound
level to the loudspeaker sound level.
System level
All digital audio inputs and outputs are referenced to 0 dBFS (digital Full Scale, the largest possible signal
that can be represented by an AES/EBU signal). Genelec DSP loudspeakers produce a sound pressure
level of 100 dB (at one meter distance in free space) for a digital input signal of –0 dBFS.
