The upper two thirds of the cabinet should be filled with damping material (green).
It is quite OK when the damping material is close to the bass driver. However,
the damping fleece should be packed loosely to ensure that the air reaches
the bass reflex tube unhindered.
The lower parts of the bass reflex tubes remain uncovered; otherwise, the sound will not leave the cabinet without disturbance.
The crossover may be placed either behind the upper or lower AC 8 HE. This ensures easy access.
It's also possible to place the cabinet on 6 cm high base that will then
accommodate the crossover.
Both bass reflex tubes should be built-in without shortening.
The terminal should be attached on the rear side of the cabinet, i.e. behind the bass reflex tubes.
To achieve the required high efficiency, it was necessary to cut-off the bass driver at a relatively high frequency; the AC 8 HE midrange driver alone cannot realise the 92 dB efficiency.
With the exception of the coil in the bass driver path, all capacitors are of high quality foil or air core type.
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