6. AMI2-70TR 100V/70V LINE INSTALLATIONS
The AMI2-70TR integrates 2 professional audio output transformers within its output allowing the
unit to be directly used for 100V or 70V line applications without needing any additional equipment. The
AMI2-70TR is configured in factory to work in a 100V line network. In order to be used in a 70V line
network it must be internally configured. See set-up diagram.
For the design of a 100V/70V line installation it is important not to lower the load impedance
below the permissible minimum impedance. The usual way to calculate the maximum number of
loudspeakers allowed for each load line is to add each loudspeaker power handling and to verify that the
sum does not exceed the amplifier maximum power.
In order to fulfill the previous principle and for the AMI2-70TR to work without problems,
loudspeakers and transformers quality must be good and calculation and installation must be correct.
7. CONSIDERATIONS
7.1. Starting up
You can power up this unit by pressing the power switch (15). In a complete audio installation, it is
important to start up the equipment in the following sequence: sound sources, mixer, equalizers, active
filters and finally power amplifiers. To turn them off the sequence should follow an inverse pattern.
7.2. Gain
The AMI2-70/TR is equipped with an effective mic input sensitivity adjustment system allowing
precise matching to incoming levels. This system uses an adjustment trimmer (17) located on the back
panel of the unit for each one of the mic channels.
7.3. Equalization
Tone controls (3, 4, 5) provide a gain/attenuation of ±15dB for each of the three bands, which are
centered at 100Hz, 2kHz and 10kHz. Because of the intended applications of this unit, it has a tone control
system that needs a screwdriver to be used in order to perform the adjust, thus avoiding any error during
the normal use procedure.
7.4. SP indicators
The "SP" signal presence indicator (2) warns of the signal presence at the inputs.
7.5. CLIP indicators
"CLlP" indicators (6, 10, 12) are turned on when the incoming signal is nearly really clipping. It is
normal that working at high power levels, the CLIP indicators illuminate at the rhythm of the low
frequencies which are the ones that passes major energetic contents. Make sure these indicators are
not permanently illuminated.
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