Norsonic Nor275, Пользовательская документация

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Power Amplifier
Nor280
The Nor280 is a rugged, lightweight and powerful class
D amplifier. It is specially designed for building acous-
tics applications.
The amplifier comes with a built in noise generator as
standard and as an option it can be fitted with a wireless
remote control for switching the signal on/off.
To optimise the power where it is needed a unique
built in equalization network compensates for the
falling frequency response of the speaker system in
both the low and high frequency areas. A part of the
amplifiers input stage is a high pass filter that removes
low frequency signals that lie below the required
frequency range for building acoustic measurements
and a low pass filter that removes all frequencies above
12kHz. This feature protects the speakers from distortion
and concentrates power into the frequency bands
where it is needed.
The output of the amplifier is short circuit protected
and an automatic system will guard against overheating
and high signal voltages through the input. The built
in cooling fan is normally not required but will run at
high room temperatures or during prolonged use of the
amplifier at full power. It will however, immediately switch
off when the input signal goes off; this feature makes
the unit well suited to reverberation measurements in
areas of low background noise.
Front panel layout
The front panel consist of a source selector, a level
attenuator, a switch selecting the equaliser on/off, input
and output connectors, mains connector, mains fuse
and switch, an error indicator and a remote indicator.
Source selector
The Source selector has four positions:
• Line. Selects the input signal connector and discon-
nects the internal noise generator. This allows the
use of an external signal source. Input sensitivity is
1 Vrms for full power output when using Norsonic
speakers.
• Pink. Selects pink noise from the internal noise
generator.
• Red/White. Selects Red/White noise from the internal
noise generator.
• White. Selects White noise from the internal noise
generator.
12 User documentation