UK_AutoMixers_V2.doc
Rev 2.0
7
For a good system working
•
Keep channel and master volume at about 80%.
•
Adjust the GAIN (1 of Fig. 1) to have, in normal working conditions, maximum output power
(out meter = 0dB 16 of FIG.1a e 1b).
•
Optimise intelligibility with channel and main equalizer.
•
Reduce MASTER volume (15 of Fig. 1a e 1b) in order to obtain the required power.
•
Be sure that mass commutator (29 of Fig. 1) is in mass-connected position.
LOUDSPEAKER CONNECTIONS (AMA 3150 and AMA 3250 only)
The device is provided with an output terminal board (35 of Fig.1a) where there are all impedances
available, for connection to constant impedance and constant voltage lines.
Moreover is provided with another multi-way output terminal board (36 of Fig.1a) with the chance
of subdivide total power on independent 4 zone selected by push buttons (19 of Fig.1a).
So could select to the outside the better loudspeakers type for the system to realize.
In Fig.3 there are any loudspeakers connections system example.
Constant voltage lines (50V, 70V, 100V)
In order to achieve the maximum efficiency of the system and to take precautions from amplifier
bad working, it is necessary to check the effective total power handling of the loudspeakers that
has to be equal or lower than the RMS power value of used amplifier. It’s a good rule arranging a
10-20% safety margin on the amplifier power capability. (equal bigger power)
Constant impedance lines (4ohm)
In order to achieve the maximum efficiency of the system and to take precautions from amplifier
bad working, it is necessary to check the effective loading impedance of the lines. The total
speakers impedance should be equal or higher than pre-selected value for connection.
To get that, each loudspeaker should be without transformer and should be connected in series or
in series-parallel groups; In any case loudspeakers should also have the same power handling.
