RCF MQ50, Руководство пользователя, Страница: 9 / 16

9
ENGLISH
CONNECTIONS
To prevent the risk of electric shock, do not connect the speaker with the amplifier switched on.
Before using the speaker, carefully check that all the connections have been made correctly to make
sure there are no accidental short circuits that could cause electrical sparks. The speaker can be
connected to constant voltage audio lines at 70 V or 100 V or to constant impedance lines (rotary
switch positioned to 16 Ohm).
1.
Turn the rotary switch (Fig. 1) and select the voltage of the line and the power to be delivered.
2.
Connect the black conductor of the speaker to the “negative” (-) of the audio line, that leads from
the amplifier terminal marked -, 0 or COM tap of the amplifier
3.
Connect the other conductor of the speaker to the “positive” (+) conductor of the audio line.
4.
When making the connections, keep the following indications in mind (Fig. 2, costant voltage).
• The input voltage selected on the speaker must correspond with the voltage selected on the
amplifier.
• The sum of the operating power values of all the speakers connected to the audio line must not
exceed that of the amplifier.
• To ensure correct audio reproduction, the connections should be made “in phase”, where the
+/- polarities of the amplifier output correspond with the +/- polarities of the speaker input.
When two speakers reproduce the same frequencies but with phase differences, these frequencies
may be annulled. In sound systems, speakers are often situated in adjacent positions and the sound
waves produced interact with each other. If a speaker is connected incorrectly; i.e. the polarity of the
audio line conductors is inverted, the audio signals are transmitted with differences in phase and
correct reproduction is therefore jeopardized.
INPUT CABLES
For connecting the speaker use cables with an adequate cross-section. The greater the distance
between the amplifier and the speaker, the larger the connection cable cross-section should be to
limit the voltage loss along the line.
To prevent inductive phenomena from giving rise to humming or disturbance that jeopardize the
effective operation of the audio system, the speaker cables should not be run together with electrical
energy conductors, microphone cables, or low level audio lines (e.g. LINE level).
To facilitate the ‘’in phase’’ connection of the speaker, use bipolar cables that have markings to
distinguish the polarity (e.g. insulation of different colours, conductors of different colours, ect.).
To minimize the inductive effects (hum) due to coupling with surrounding electrical fields, use cables
with conductors braided together.
Pa
= Amplifier power
Pd
= Speaker power
n
= Number of speakers
Vd
= Speaker input voltage
Va
= Amplifier output voltage
Amplifier
Pa > Pd x n Va
Vd = Va
+
-
-
+ - +
Vd = Va
Fig. 2
-
+
Vd = Va
Fig. 1