The HSA amplifiers are supplied with plastic washers so they can be mounted in a rack without
damaging the mounting flanges.
3.2. Mains connection
The amplifier is powered with alternating current, depending on the country, 110-120, 220-240V
50/60Hz. (see specifications plate on the device), and its maximum power draw is 482VA.
The amplifier must be connected to proper grounding ( resistance, Rg=30 or less).
Avoid intertwining the mains cable with the shielded cables that carry the audio signal, as this could
lead to interference and humming.
In order to protect the unit from an eventual electrical overload or momentary power peaks from the
internal circuits it is fitted with a fuse. Should it ever blow, unplug the unit from mains and replace it with an
identical one. If the new fuse blows again, contact our Authorized Technical Service immediately.
CAUTION: IN NO EVENT SHOULD A FUSE OF HIGHER VALUE THAN THE NOMINAL
VALUE BE INSTALLED.
3.3. Signal input connections
On it rear panel, the HSA300 amplifier has an analogue, balanced and line level input signal.
The signal input connectors are three pin Euroblock connectors (11). The assignment of the
connections is as follows:
Live or direct signal
Cold or inverted signal
Ground
For unbalanced connections short the - terminal to ground.
The input impedance is 22k (balanced) with a nominal sensitivity of 0dBV (1V). This impedance
allows for a large number of amplifiers to be connected in parallel without degrading the sound quality.
3.4. Output connections
The OUTPUT section on the rear panel is fitted with a two pin (10) Euroblock connector. During
the wiring tasks of one or more amplifiers, always respect the relative polarity of the outputs (+ and -
markings on each output connector), cabling and speakers.
3.5. Internal switch for pass-high filters
Inside the amplifier there is a ("jumper") switch to enable / disable the high-pass filter of the
amplifier, with a cut-off frequency set at 70Hz and with a slope of 18dB / octave. It is recommended that
in certain applications the high pass filter should act on the 100V line, especially when the audio
playback content is primarily vocal (paging announcements, for example).
Refer to section 6.5. Block diagram and 6.3. Configuration diagram for further information.
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Terminal +
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Terminal -
Terminal
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