Sennheiser Digital 9000, Инструкция по эксплуатации

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Using the EM 9046
58 | Digital 9000
The selection of a suitable booster frequency range depends on several
factors:
• Required number of transmission links
• Sufficient number of unused frequency presets
• Sufficient number of transmitters of the correct type (in this example,
transmitters of type B1–B4 or B5–B8, see page 39)
• Recommended transmission mode “ HD ” or “ LR ”:
“ HD (High Definition) ”: Transmission of an audio signal without audio
data compression. As a result, the audio signal remains pure and
unadulterated. In “
HD ” transmission mode, the range can be restricted
compared to “ LR ” transmission mode.
“ LR (Long Range) ”: Transmission of an audio signal whose bit rate is
reduced – before transmission – by an audio data compression tech-
nique (SeDAC, Sennheiser Digital Audio Codec). This compression tech-
nique provides excellent audio quality and a large transmission range.
The sensitivity to interference is reduced compared to “
HD ” transmis-
sion mode.
Let us assume that you want to set up 8 transmission links and transmit
in “
HD ” transmission mode with the maximum possible transmission
range.
Have a look at interference zone “ HD ” (see also above diagram): All
booster frequency ranges except for B6 provide a sufficient number of
unused frequency presets.
Example 1:
8 transmitters of type B1–B4
Let us assume that you have 8 transmitters of type B1–B4:
You can use any of the booster frequency ranges B1–B4 but you should
select the booster frequency range with the highest number of unused fre-
quency presets: B1.
Interference levels of
antenna A/B in
interference zone
“ HD ” “ HD/LR ” “ LR/HD ” “ LR ”
Recommended
transmission mode
“ HD ”
“ HD ”
*
or “ LR ”
“ LR ” or “ HD ”
**
“ LR ”
*
* Transmission mode can be used with a restricted range
**
It might be that the transmission mode can only be used with a severely restricted range
Booster frequency
ranges
B1 B2 B3 B4 B5 B6 B7 B8
Number of unused fre-
quency presets in inter-
ference zone “HD”
40 35 27 36 29 6 26 31
Can the booster fre-
quency range be used?
–
Is there a sufficient
number of transmitters
of the correct type?
– – – –