Crown IQ-USM 810, Справочное руководство

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IQ-USM 810 IQ Digital Processor / Digital Mixer
IQ-USM 810 Reference Manual
4.2.3 Output Level Meters
Audio level meters are provided for each output. The
meters sense the audio signal immediately after the
audio output processing block, and respond with
1.7-millisecond attack and 350-millisecond release.
Meter range is from –60 to +20 dBu with
1 /
2
-dB
resolution.
4.2.4 Output Dynamic Cut/Boost Meters
Meters are provided for each output to indicate the
overall cut or boost being applied from all signal pro-
cessing features that affect output gain, including Am-
bient-Leveler and Output Limiter. Meter range is from
–60 to +20 dBu with
1 /
2
-dB resolution.
4.2.5 Memory Backup
The IQ-USM 810 settings are stored in high-endurance
flash memory whenever a parameter is changed.
changed settings are updated every few seconds.
4.2.6 Presets
The parameters for all functions within the IQ-USM 810
can be saved as presets and each can be given a
unique 32-character name. A total of 32 user presets
can be stored in the IQ-USM 810’s flash memory. Pre-
sets can be recalled via the front-panel selector but-
tons, IQ for Windows preset selector controls, from
within events, or by an external system controller via
the Multi-Function Control Port.
• • • • • Preset Segue: When a preset is selected, the
Preset Segue feature provides a smooth transition
to the new preset. Preset Segue can be set to ei-
ther a fixed time in seconds or a fixed rate in dB
per second. Range for fixed time in seconds is 1
to 255 seconds. Range for fixed rate in dB per
second is from 0.5 dB to 40 dB.
4.2.7 Real Time Clock
The onboard Real Time Clock tracks day, date, hour,
minute and second, and may be set to any date and
time desired, or to match that of the computer running
IQ for Windows software. The clock is used as a time
reference for the Events Scheduling feature. Internal
capacitor storage allows the clock to run for up to 45
days without power being applied to the IQ-USM 810.
4.2.8 Events
User presets can be scheduled for recall as an Event at
a specific date and time, and also can be set to repeat.
A total of 32 Events can be scheduled, and each Event
can be given a unique 32-character name.
4.3 Input Signal Processing
Note: The following features are controlled and moni-
tored via IQ for Windows software. Refer to Figure
5.2,
IQ-USM 810 Signal Flow Block Diagram for fea-
ture locations in the audio signal chain.
4.3.1 Input Filters
The input signal can be filtered with any combination of
up to eight different filter types. Different filter types
include the following:
Low-Pass Crossover Filter (1st-4th order)
High-Pass Crossover Filter (1st-4th order)
Parametric Equalization Filter (2nd order only)
Low-Pass Equalization Filter (2nd order only)
High-Pass Equalization Filter (2nd order only)
High-Pass Shelving Equalization (1st order only)
All-Pass Filter
32 filters per DSP processor are available for a total of
128 filters within the IQ-USM 810. An indicator in IQ for
Windows software shows how much of the DSP re-
sources are being used by the selected filters.
The chart in Figure 4.2 shows how processing is allo-
cated to each of the four DSP processors.
One 3rd- or 4th-order filter uses the equivalent of two 1st-
or 2nd-order filters.
1st-, 2nd-, 3rd- and 4th-order responses result in 6-,
12-, 18- and 24-dB/octave roll-offs, respectively.
All filters with adjustable Q-factors can be set in frac-
tions of an octave.
All filters have IIR-based topologies to ensure a proper
magnitude/phase relationship for use in professional
audio applications such as equalizer or crossover (di-
viding) networks.
Figure 4.2 DSP Processor Allocation