Dolby Laboratories DA20, Руководство по установке

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2-64
When the backplane wiring is done as shown in the figure, the operation of the Cat.
No.517s for the S, P (left surround), and Q (right surround) channels is as follows:
The optical surround trim (the upper pot on the left-hand Cat. No.517) now functions as
a surround trim governing all three surround outputs at once when an analog optical
format with surround (formats 04 or 05) is selected. A range of + 10 dB around the
nominal setting is provided. In all other formats, this pot is disabled.
If Cat. No. 64 EQ cards are being installed in the accessory unit for the first time, the
surrounds must be equalized. Refer to the CP200 Installation Manual, page 47.
2.5.3.4 Equalization of the Subwoofer Channel
Refer to the Cat. No.441 alignment instructions on the following pages (from the CP65
Manual).
Remove the Cat. No.141 from slot 23 (fourth slot in from the left), insert the Cat. No.85 in
its place. If Le and Re speakers are also installed, remove the Cat. No.141 from slot 35
(third slot in from the right). Select format 42 (Dolby Stereo 70 mm). Select Le on the Cat.
No.85 to send pink noise to the subwoofer. Use a calibrated microphone and a RTA to
EQ the subwoofer channel according to the instructions. After completing this step,
reinstall the two Cat. No.141s into slots 23 and 35.