EM Acoustics HALO bi-amplified line array system - Manual (Page 31)

Page 31 of 39
HALO system User Manual
V2.2 August 2010
4. Lie the enclosure on its side, and remove the screws holding the side grille in
place. Place this to one side. Gently ease the HF drive unit out of its chamber,
being aware to ease the cables through the connection hole as they are delicate.
Note the three acoustic absorption foam blocks behind the drive unit.
5. To re-instate the HF drive unit, position the drive unit above the chamber and
thread the cables through the holes.
6. Compress the three foam blocks which sit behind the HF drive unit. As you ease
the HF drive unit into its housing, ensure that the absorption blocks are also
moving into the chamber. You may find a flat piece of plastic or thin plywood such
as a ruler may help to keep the foam compressed as you are sliding it into position.
NOTE: Under no circumstances use a metal ruler – the magnet system in the HF
drive unit is extremely powerful and you may accidentally damage the ribbon
membrane.
7. Once the drive unit is properly seated in the chamber, replace the side grille and
reinstate the screws holding it in place.
8. Inspect the front of the HF drive unit diaphragm for any metal fragments – the
conductors are exposed and as such small conductive fragments can cause the unit
to short-circuit.
9. Replace the steel bars compressing the diffraction blocks on the front of the drive
unit, ensuring they sit correctly at the edges of the drive unit aperture.
10. Use a silicone sealing compound around the hole in the MF chamber wall to make
sure the cable hole is airtight. Then reconnect the HF drive unit cables to the
terminal block, ensuring the correct polarity.
11. Replace the MF drive unit as described above.
HALO-S Subwoofer – LF drive unit removal
1. Remove the four countersunk screws on each side of the enclosure retaining the
grille. Remove the grille and set to one side.
2. Remove the flying pins on the side of the enclosure with the drive unit you want to
remove. The enclosure can then be stood on this side (so the drive unit to be
removed is facing upwards), ensuring that the pins are not trapped underneath.
3. Using an Allen key, remove the six bolts securing the drive unit. Carefully lift the
drive unit out of its mounting hole, being careful to avoid damaging the drive unit
above. Disconnect the cables (noting polarity) and remove the drive unit fully.