Connections; Choosing An Appropriate Pa Amplifier - Omnitronic LI-204 I Bedienungsanleitung

Operate the speaker system only after having familiarized with its functions. Do not permit operation by
persons not qualified for operating the speaker system. Most damages are the result of unprofessional
operation!
Never use solvents or aggressive detergents in order to clean the speaker system! Rather use a soft and
damp cloth.
Please consider that unauthorized modifications on the speaker system are forbidden due to safety reasons!
If this speaker system will be operated in any way different to the one described in this manual, the product
may suffer damages and the guarantee becomes void. Furthermore, any other operation may lead to
dangers like crashes, hearing loss etc.
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CONNECTIONS

Choosing an Appropriate PA Amplifier

This speaker system must only be connected to an appropriate power amplifier. The amplifier power must
correspond with the speaker system power. An amplifier with too little power can also destroy a speaker
system with a higher power range.
Before starting with the installation, you must clarify how many speaker systems you would like to install in
the room. In order to increase the sound pressure level two speaker system pairs should be connected with
the power amplifier. Please note that the impedance is only half the value when you connect two speaker
systems with one channel of the power amplifier. Please make sure that the power amplifier is qualified for
this operation mode.
When connecting further speaker system pairs (e.g. 3 pairs) to the same power amplifier, the impedance
lowers even further. You must always make sure that the power amplifier is qualified for the new impedance.
If the impedance of the speaker system is lower than the lowest allowed amplifier impedance, the amplifier
and the speaker systems may be damaged. Furthermore, you must define the operation mode for your
system. If the power amplifier is to be used in stereo mode, the power is lower as in e.g. mono bridged
mode. The following descriptions refer to OMNITRONIC power amplifiers. You may also use other
appropriate power amplifiers.
Example for the Calculation Number of Speakers/Impedance
Number of speakers
1 speaker at 8 Ω
2 speakers at 8 Ω each
2 speakers at 8 Ω each
3 speakers at 8 Ω each
3 speakers at 8 Ω each
4 speakers at 8 Ω each
The input impedance of the speaker systems should at least be the same or even higher than the output
impedance of the amplifier.
Operating Modes
The most frequently used operating mode of a power amplifier is stereo operation, where both channels are
operated independent of each other. In parallel operation the power amplifier can be operated in mono
mode, i.e. via one input channel. The voltage remains the same, the current is doubled. Consequently, the
output impedance is limited to the minimum value of one individual channel. In bridge operation the power
amplifier can be operated in mono mode, i.e. via one input channel. The voltage is doubled and
subsequently also the output impedance. For stereo operation two amplifiers are needed. Always make sure
the power amplifier's selector switch for the operating mode is set accordingly.
≙ ≙ ≙ ≙ Impedance
8 Ω
4 Ω (parallel)
16 Ω (in line)
2.66 Ω (parallel), only for amplifiers capable of handling 2 Ω
24 Ω (in line)
2 Ω (parallel), only for amplifiers capable of handling 2 Ω
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