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5.
Adjustment of magnetic/digital subwoofer level.
a.
Systems with subwoofers but no Le or Re speakers.
Select format 42 (Dolby Stereo 70 mm). Select Center on the Cat. No.85,
using a RTA observe the level of the pink noise from the center channel,
note the amplitude on the display. Note: This is not the same level as
observed in step 4. Shut off Center on the Cat. No.85 and select Le. While
observing the RTA, adjust the Mag/Dig subwoofer level control on the Cat.
No.560 so that the subwoofer inband level is 10 dB higher than the center
channel midrange level previously observed. After completing this step,
proceed to step 6.
b.
Systems with subwoofers and Le Re speakers.
Select format 42 (Dolby Stereo 70 mm). Select Center on the Cat. No.85,
using a RTA observe the level of the pink noise from the center channel,
note the amplitude on the display. Note: This is not the same level as
observed in step 4. Shut off S1 (subwoofer enable) on the Cat. No.560 to
mute the subwoofer output. Shut off Center on the Cat. No.85 and select
Le
. While observing the RTA, adjust the Mag level control on the Cat.
No.142 so that the Le inband level is 10 dB higher than the midrange level
of the center channel that was previously observed. Turn on S1 on the Cat.
No.560 card. Remove the Cat. No.141 switch card from slot 35 (third slot in
from the right) to disable the other stage speakers. While observing the
RTA, adjust the Mag/Dig subwoofer level control on the Cat. No.560 so that
the subwoofer inband level is 10 dB higher than the center channel
midrange level that was previously observed. Note: The Le and Re
speakers are only used in mag formats with the Cat. No.560 and the Opt
control on the Cat. No.142 is not used.
6.
Remove the Cat. No.85 and reinstall all Cat. No.141 cards. The B-chain
adjustments of the new cards are completed.
