Audio Developments AD114 - Manual (Page 16)

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The Microphone/Line input module functions are as follows: Switch (1) selects 48V
phantom power for condenser microphones. Powering may be selected before or
after connecting the microphone, but switch off all powering on unterminated
modules to ensure unconditional stability of the mixer. For complete safety of
external equipment, switch off microphone power before connecting a line-level
signal.
Phase change (4) is pre transformer and operates on microphone and line inputs.
∅
1
is the normal position.
The high-pass filter is pre transformer and, similarly, operates on microphone and
line inputs. In this position the filter protects the transformer from low-frequency
saturation caused by wind, traffic, air conditioning etc. Operating frequencies are to
be found in the TECHNICAL SPECIFICATION. The high-pass filter operates
independently of the equaliser.
The input gain of the microphone amplifier is set by the 6-position switch (3). The
range of this control is 50dB in 10dB steps. For line-level signals, an input attenuator
is inserted via switch (2).
Following the microphone amplifier is the simple, but effective, equaliser as used in
the AD245 - selector switch (6). Amplitude controls are HF (11) MF (12) and LF
(13).
Two push-button switches - (7) routes the module’s signal proportionately between
the left and right mix busses.
Pre-fader listen (8) with its LED indicator (9) routes the module’s signal to the
monitor/PFL mix buss for auditioning on headphones.
An overload LED (10) illuminates 3dB before clipping at the input to the fader.
The Penny & Giles fader (14) is calibrated at the fully open position. Faders on
adjacent modules can be coupled for stereo operation by the use of standard
ganging clips.
Line input module - The facilities incorporated in this module are identical to that of
the Microphone/Line module except there is no microphone powering, no
microphone/line select and input switched gain control. The latter is replaced by a
rotary potentiometer with a gain variation range of +/- 6dB