Formula Sound AVC2, User Manual

GENERAL DETAIL

The AVC2 is a stereo unit and performs as an intelligent volume control.  The operation is
very simple.  If the average operating level is kept below the internally set threshold the AVC2
has no effect.  If the average programme level exceeds the threshold AVC2 will reduce its
output level.  The level is reduced in discreet steps indicated by the led bargraph meter on
the front panel of the unit.  The action of the AVC2 is to fade between these steps and is
almost undetectable in use.  The more one tries to increase the volume the more the AVC2
will decrease it so that the system will barely change in perceived level.  If driven to maximum
attenuation the output level will be reduced by more than the increase in input level.  The
mixer or pre-amp feeding the AVC2 will probably be clipping but the system will actually be at
a lower than normal level.  A clip indicator is provided to show when the input stage of the
AVC2 is being over driven.  Reducing the input level will gently release the attenuation pro-
vided by the AVC2.

The AVC2 has no external controls for the operator to worry about - just a bargraph meter
and some indicator led’s to inform the operator of the status of the unit.

An external remote warning indicator may be connected to warn the operator that the operat-
ing level is 3dB away from the threshold at which the AVC2 will start to control level.

A mute relay is fitted which can be operated by an external switch to improve system security
or a fire alarm connection to mute the system in case of fire.

A provision is also included to dim the unit by 20dB.

The AVC2 also has provision to connect an external time switch (not supplied) to switch
between two output levels.

 As local conditions and noise control specifications can vary these  facilities allow the unit to
be used in several ways to comply with regulations.

For more detail see the section on AUXILIARY CONNECTIONS on the next page.

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