INPUT ATTENUATORS
Each power amplifier channel has a input signal attenuator, gauged. The
calibration is measured between ±0.5 dBu.
The input attenuators are independent for each channel in STEREO
mode. In the models MF16 and MF24 in mode MONO it is selectable the control
of the input attenuators over the channels (independent or both channels depen-
dent on the CH1 input attenuator) (for more information see section SPECIAL OPERATIONS -
INPUT ATTENUATION CONFIGURATION IN MONO MODE).
In the models MF8 and MF12 in mode MONO, the input attenuators are independent for
each channel. In mode BRIDGE both channels depend on the CH1 input attenuator.
BRIDGE MODE INDICATOR
The red BRIDGE LED
illuminates when the power amplifier is working in BRIDGE
mode.
CLIP INDICATORS (INPUT SIGNAL OVERLOAD)
The CLIP red LED
, illuminates when the power amplifier starts to saturate,
moreover, if the limiter is ON, this LED indicates that the circuit limiter starts to work (for more
information see section SPECIAL OPERATIONS- LIMITER CONFIGURATION). The CLIP indicators
are independent in each channel, and indicates a real saturation, by comparing
input and output continuously, and are independent of the mains voltage.
The CLIP indicators
also illuminates when there is a output short-circuit or
when a protection (DC or thermal) of the power amplifier disconnects the input, whenever
one input signal is being introduced to the power amplifier.
To make the loudspeakers life longer, avoid this situation of overload during for ex-
tended periods of time.
If the input signal level is too high, don't turn the power amplifier limiter off, because it is
an efficient protection for the loudspeakers.
In general, the loudspeakers resist high peaks of instantaneous power, but when
exposed power to extended saturations they lose any guarantee of good operation.
The saturation measuring circuit is sensitive to peaks, it has a quick attack time and a
slow release time.
SIGNAL INDICATORS
The SIGNAL green LEDs
illuminates when the output signal of the corre-
sponding channel reaches 25 dBu before saturation.
These LEDs indicate signal presence in the power amplifier input.
This SIGNAL
measurement circuit is sensitive to peaks, it has a quick attack
time and a slow release time to indicate the average power.
ALTAiR
PROFESSIONAL POWER AMPLIFIERS MF SERIES
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