The crossover - open to the rear - should be placed on the rear wall behind the tweeter or midrange driver. Should the crossover also be enclosed a small board of 450 x 172 mm is needed.
Since the cabinet is slim and relatively high a loudspeaker stand of at least 25 cm width should be used.
. For the bass driver compartment no damping material is usually needed. As an improvement two mats of Bitumex - placed on the rear wall - are recommended.
The high frequencies gain in detail and definition when the edges are angled or rounded.
Should further improvements be required, it is suggested to glue 4 mm mats of Bitumex to the left, open inner wall below the bass reflex tube.
Slanted or rounded front edges will improve on high frequency definition.