Operation - Adastra V-122 User Manual

There is an option on each zone for either a 4Ω or 8Ω speaker output to determine the minimum impedance.
It is essential to select the correct output terminal when opting for low impedance speakers.
For a single 8Ω speaker, connect the positive (+) wire to the "8Ω" terminal and the negative (-) wire to "COM"
For a single 4Ω speaker or for 2 x 8Ω speakers connected in parallel, connect the positive (+) wire to the "4Ω"
terminal and the negative (-) wire to "COM"
To drive multiple low impedance speakers from a single 4Ω or 8Ω output, these can be connected in series or
parallel to achieve the correct impedance, which should be no less than 4Ω or 8Ω, depending which is used.
3 examples: 2 x 8Ω speakers wired in parallel will present 4Ω to the output.
2 x 8Ω speakers wired in series will present 16Ω to the output.
2 pairs of series-wired 8Ω speakers (i.e. 2 x 16Ω) wired in parallel will present 8Ω to the output.
Most importantly, check total the combined impedance on the speaker wire to the amplifier before connecting
it to the output. It is important to ensure that the total combined speaker load is no less than 4Ω or 8Ω
(depending which output is used) and that the power handling of the speakers is equal to or greater than the
output power of the amplifier.
When all other connections are made, connect the rear IEC inlet (13) to the mains using the supplied mains
lead (or an equivalent approved type).
Ensure the POWER (12) is switched off until all input and speaker connections are in place.

Operation

When all connections are made, turn down both MASTER controls (10) and switch on the power (12).
The backlight on the media player display will light (1) confirming that power is on.
Turn BASS and TREBLE controls (8, 9) to the 12 o'clock position (pointing straight up) and turn MASTER
rotary controls up part way for testing.
To check the system using one of the mic/line inputs 1, 2 or 3, ensure a signal or microphone is connected
and gradually increase the volume for that channel until the output is heard through the speakers. Turn up
the MASTER control to the maximum required volume level and adjust the individual volume as required.
LINE inputs A or B or the AUX input can also be used for the initial check, or even the internal MEDIA player.
When checking audio through LINE A, LINE B or Aux, ensure that its level control is not turned fully down.
See below for further information about music playback source selection and operation of the media player.
LED indicators for each channel (11) show when the signal is present (-20dB) or at maximum (0dB).
If the 0dB LED is lighting constantly rather than briefly on the loudest peaks in the sound, reduce the output
level to where this lights only instantaneously to help avoid any damage to the system.
If the amplifier detects overload or a fault, the amplifier will enter Protect mode and the PROT LED will light.
If this happens, power the amp down, check the speaker wiring for faults and re-start after a few minutes.
If the amplifier stays in Protect mode permanently, have the unit checked by a qualified service technician.
Once initial system checks are complete, repeat the process for any other mic/line/aux inputs, playing a signal
through each and gradually increasing the volume for each to the required level (3, 4, 5).
Note: Mic/Line 1 input also has a PRIORITY switch (21), which when pressed in, overrides (mutes) output of
the other channels when a signal is present on Mic/Line 1. If there is no sound from any other channels, it is
worth checking if this button is pressed in, which could cause the other channels to mute.
Music playback is served by a rotary source selector (6) for each zone, which can switch between AUX,
MEDIA, LINE A or LINE B. This offers each zone to be able to "hear" the same or different music playback
(which can equally be any line level input type).
953.251UK, 953.252UK User Manual