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Several levels of protection to avoid accidential mis-settings (user security levels)
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Remote control and link functions of the monitors via RS 232 or MIDI
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An output for an additional subwoofer is provided. FIR filtering for this output is provided inside
the O 500 C.
Power amplifier:
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The O 500 C is fitted with high-performance, state-of-the-art power amps, which can deliver
clean 400 W RMS for the woofer, 230 W RMS for the midrange dome and 290 W RMS for the
tweeter.
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Stacked power-supply for better amplifier efficiency
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Very low non linear distortions: woofer< -110 dB, midrange < -100 dB, tweeter < -90 dB
1.3 Block Diagram
In Fig. 1.3/1 all modules which are included in the digital active studio monitor O 500 C can be
seen. All modules shown are integrated in the monitor cabinet:
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Digital controller
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Three power amplifiers
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PCB with display, IR-receiver and illuminated logo
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PSU with torrodial transformer, PCB and regulators
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3 drivers
All audio parameters, except for the power amplifiers, are controlled by the internal DSP. An analog
signal, connected to the O 500 C, will be A/D converted and then fed to the DSP, where all parameters
selected are processed in the digital domain. When the signal has passed all stages in the DSP, it
will be D/A converted and then sent to the analog power amplifiers. The analog output signal to the
external, optional subwoofer can be taken from the transformer-balanced XLR output on the rear
of the monitor. The power amplifiers of the O 500 C have been designed in a bipolar topology and
are built onto one PCB. Heavy-duty alloy heatsinks with a large surface allow for high power
performance under „cool“ conditions.
The digital controller consists of a DSP-PCB, which carries the A/D and D/A converters with the
analog input and output stages, plus the powerful DSP. A further PCB carries the microcomputer
which contains the controller software plus the „core of the system“ the 8 Bit microcontroller.
Both PCB’s are shielded in a MU-metal case to avoid hum and side noises.
The VF display of the digital controller, the limit signalling and the IR receiver are mounted at the
top of the front baffle.
The power supply system has separate voltages for the analog and digital signals, as well as for
the power amplifiers. On the DSP and the microcomputer PCB an additional stabilisation is provided,
again separated for the A/D and the D/A signal paths.
