Справочное Руководство для Crown studio reference i

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Studio Reference 

IIIII & II

  Professional Studio Amplifiers

Each channel’s output level can be adjusted accurately
using the 31-position detented level controls on the front
panel (see Section 4.4).

During normal operation of the amplifier, the 

ODEP

(Output Device Emulation Protection) indicators glow
brightly to show the presence of reserve thermody-
namic energy. They dim proportionally as energy
reserves decrease. In the rare event that energy re-
serves are depleted, the indicators turn off and 

ODEP

proportionally limits the output drive so the amplifier can
safely continue operating even under severe conditions.
These indicators also help to identify more unusual op-
erating conditions (see Figure 4.2).

The 

IOC

 (Input Output Comparator) indicators serve as

sensitive distortion indicators to provide 

proof of

distortion-free performance

. Under normal conditions,

the indicators remain off. They flash if the output
waveform differs from the input by 0.05% or more (see
Section 4.2). If the input signal level is too high, the
indicators will also flash brightly with a half-second hold
delay to show input overload or output clipping. 

Note:

The channel 2 IOC indicator stays on in Parallel-Mono
mode.

 See Section 4.2.

These indicators flash synchronously with the amplifier’s
audio output to show signal presence. 

Note: These indi-

cators may not flash at very low input signal levels.

 See

Section 4.2.

This indicator lights when the amplifier has been “en-
abled” or turned on, and AC power is available.

This push button is used to turn the amplifier on and off.
When turned on, the output is muted for about four sec-
onds to protect your system from start-up transients.
This is why a power sequencer is rarely needed for mul-
tiple units. (The turn-on delay can be changed. Contact
Crown’s Technical Support Group for details.)

The dust filter removes large particles from the air drawn
in by the cooling fan. In most cases, the fan will not run
so the filter will remain clean. If the filter becomes dirty, it
can be removed for easy cleaning (see Section 4.5).

A five-segment output meter is provided for each chan-
nel. The meters are factory-set to show dynamic range
of the signals in dB, which is computed as the ratio of
peak to average output power. Also, the meter can op-
tionally be set to show output levels (see Section 4.4).

❏  Meter Switches

Two switches behind the front panel can be used to
customize the output meters (H). By default, the meters
display dynamic range. To make the meters display sig-
nal levels or to turn them off, see Section 4.4.

®

Fig. 2.1  Front Facilities