Use a minimum of two coupled, poses on the floor.
The ideal, 8 units per channel.
Directions for use: high-pass filtering 50 Hz, 2 units, or 40 Hz, 8 units, 18dB/octave
Lowpass filtering 250Hz Max, 18 24dB/octave. Au-del there will be a coloring inhrente this type of load.
Use of Hps quality (origin: JBL K151 now deprecated; JBL 2242 usable). Privilgier to loudspeakers strong BL, max 150g moving mass, the magnetic linear circuits. Including the JBL or RCF.
Not at all made for the sub, absolutely avoid the bowls and heavy membranes rsonance low.

In active filter sr well, with quality amp.

Why is this box?

Well when the sound shall be immediately used by seducing his punch and his place in the serious ridicule on the bass RFLEX or other direct radiation ... its flag on the right. At high power it is a slap phnomnale.
A bit like the B115 Martin (descending lower course) or former Turbosound, excellent vintage.
Costing a very lively, which is rediscovering the music!
Setbacks beyond mdaille: they are bulky and not descend very low frequencies.

A well used to obtain the quintessence.