Optimus AM-30 Installation And Operating Instructions Manual page 15

AM-30 / AM-60
Amplifier
Turn the correspondent front control knob clockwise or counter-clockwise to increase or decrease
the volume of this input.
4.3. Manual priority contact
Closing this contact, inputs MIC2 and AUX/CD will be mute.
4.4. Loudspeakers connection
This equipment has different loudspeakers outputs such as 100 V, 70 V and low impedance. It's
only possible to use one output at the same time, connecting more than one may damage internal
parts of the amplifier.
4.4.1. 100 V line
These loudspeakers are most commonly used in Europe for PA distribution. When the amplifier is
at full output 100 V RMS will be present at the output terminals. Only use 100 V line loudspeakers
with this output. All loudspeakers are wired in parallel and the sum of their power must not exceed
the rated output power of the amplifier. It is advisable not to load the amplifier at more than 70% of
its rated output power when using music sources.
4.4.2. 70 V line (inner PCB selectable)
This system is common in the USA, it operates on the same principles as 100 V line except that at
rated output power the amplifier has 70 V RMS on its output terminals.
The switch from 100 to 70 V has to be carried out inside the amplifier by changing the connection
of output transformer taps.
4.4.3. Low impedance (4 Ω, 8 Ω, 16 Ω)
This output allows connection of standard low impedance loudspeakers, the minimum load
impedance is 4 Ω. When two or more loudspeakers are used ensure that they are wired in such a
way that load impedance remains between 4 Ω and 16 Ω.
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AM-30 / AM-60 Version 1.0