Biamp A4 - Manual (Page 25)

Introduction
Channel Failure (CF) Alarm indicates that a hardware failure of the amplifier module
has occurred. Audio will be stopped on that channel and channel or device failover will
occur, if enabled.
Excessive Clipping (EC) Warning indicates that amplifier output clipping has occurred
(or would have occurred if the Clip Limiter had not been enabled) and is affected by the
Clip Count Threshold parameter (see Clip Count Threshold below).
Low Impedance (LZ) Warning indicates that the impedance monitoring circuit (if
enabled) has detected an impedance that is lower than the minimum allowed by the
current setting of the Tolerance parameter (see Band Setup below).
High Impedance (HZ) Warning indicates that the impedance monitoring circuit (if
enabled) has detected an impedance that is higher than the maximum allowed by the
current setting of the Tolerance parameter (see Band Setup below).
Other Control Dialog Parameters
HS Temp % Max indicates the temperature of the heat sink located on the amplifier module,
given as a percentage of maximum cooling capacity. If the heat sink temperature rises to 92%, a
Heat Sink (HS) Warning will occur and the amplifier module will attenuate its output by 3 dB to
attempt to reduce the temperature of the heat sink. If the heat sink temperature rises to 100%, a
Heat Sink (HS) Alarm will occur and audio on that channel will be stopped.
Clip Count Threshold is the number of consecutive 100 ms segments of audio containing at
least one clipped sample that are needed to illuminate the Excessive Clipping (EC) Warning
indicator. The Clip Count Threshold affects the response of the EC Warning indicator; if the Clip
Count Threshold is set to 1, the Excessive Clipping (EC) Warning indicator becomes a “standard”
or instantaneous clip indicator, rather than an “excessive” or long-term clip indicator.
Mute Out is used to mute the audio on that channel. Gain Out (dB) is used to set the amplifier
sensitivity. This control ranges from 0 dB (unity gain) to 24 dB (default is 12 dB). Invert Out is
used to reverse the polarity of the output signal. Clip Limiter Out is used to control whether the
analog clip limiting circuit on the amplifier module is enabled or not. When enabled, this limiter
attenuates any signal peaks that would otherwise cause the amplifier’s output to clip. Peak Out
is a signal peak indicator that illuminates when the output signal is within 3 dB of clipping the
amplifier.
Impedance Parameters
Load is a setting that allows the user to select the intended speaker load (4, 6, or 8 Ohm) for all
channels controlled by that block. Choosing Auto Detect will allow the AM600 amplifier module to
automatically set the load impedance based upon the amplifier output current. This setting is only
available if the Amplifier Mode has been designated as Low Impedance. (See Amplifier Mode
above)
Band Setup produces a control dialog window that allows the Impedance Monitoring algorithm to
be configured. The text on the button control will indicate the number of frequency bands that
have been defined for impedance monitoring.
Impedance Monitoring Active (IMA) is an indicator that illuminates when impedance monitoring
is active.
Frequency Band Setup
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