Dolby Laboratories 430 operating instructions Dialog

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In situations where the interference is broadband, both the LF and HF bands can be used in varying amounts. The two expander sections are in series therefore their effects tend to sum. For this reason, it will be found that the amount of processing used can often be reduced when both bands are brought into play since they broadly overlap in the band 200 Hz to 2 kHz.

(+4 dB) 0 VU

 

 

 

Dialog

 

 

 

 

–10

 

 

 

Range

–20

 

 

 

}

–30

 

 

 

 

–40

 

 

 

 

–50

 

 

 

 

–60

 

 

 

 

–70

 

 

 

 

–80 VU

 

 

 

 

20 Hz

100 Hz

1 kHz

10 kHz

20 kHz

For each band, there is an untreated path which is mixed with the treated path in variable amounts determined by the position of two controls on the remote unit in such a way that, for nominal level signals, the change from untreated path to treated path causes no audible change in level. This is useful because it allows the sound engineer to treat the noise rather than having to juggle with the predominant signal. As the amount of untreated signal increases, it progressively dilutes the effect of the processing without changing thresholds, forming a natural progression from processed to linear effect.

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Contents Series Dolby Laboratories Incorporated Dolby Background Noise Suppressor Specifications Table of Contents Introduction Model 430 System Section Unit Configurations430SK1 1 Channel Suppressor KIT AccessoriesControls Section OperationPractical Operation Console Signal Path Insertion GuideMain Control unit and Suppressor Frames Section InstallationMain Channel Number Assignment Console Mounting of RemotesPanel Cut-Out Templates for Cat. No Remotes Style Plugs Regulatory NoticesIEC Notices Important Safety NoticeSection Theory of Operation Dialog Cat. No Voltage Regulation/Smoothing SectionAppendix A1 Plugging Precautions