Dolby Laboratories DA20, Руководство по установке

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2-50
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.
When no accessory unit is installed the surround EQ sections of the Cat. No.560 are used
to equalize the P and Q channels (the S channel will not be equalized). Select format 40
(70 mm mag, no NR). Remove the Cat. No.141 from slot 37 of the CP200 processor unit
(first slot in from the right) and insert the Cat. No.85 Pink Noise Generator in its place.
Be sure to mute the processor when removing or inserting a card.
Note: the Center
switch on the Cat. No.85 will send pink noise to P (left surround) and the Surround
switch will send it to Q (right surround).
Use a calibrated microphone and a real time analyzer (RTA) to equalize the surround
channels according to the following instructions (from the CP65 manual). The
instructions explain the alignment of a Cat. No.441 card, however the Cat. No.560 EQ
section
is identical. References to gain settings (on Cat. No.242) should be interpreted to
be Cat. No.517 gain settings.
After completing these steps, reinstall the Cat. No.141 into slot 37 and proceed to the
section Equalization of the Subwoofer Channel (Section 2.4.3.4).