It is an actively driven two-way bass-reflex design housing three long excursion neodymium 21" drivers of which two face to the front while the other radiates to the rear of the cabinet. The two forward facing drivers are housed together in a bass reflex chamber and are driven from a single channel of the D12 amplifier. The backward facing driver is in a second chamber and is driven by the other D12 channel.
Through this driver setup its cardioid dispersion pattern avoids unwanted energy behind the system and greatly reduces the reverberant field at low frequencies providing highest accuracy in low frequency reproduction. The hypercardioid mode in the D12 amplifier optimizes the tuning of front and rear channels for a maximum rejection at the left and right sides behind the cabinet.
J-INFRA cabinets can only be used in ground stacked configurations in conventional left/right setups as well as arranged in an Infra subwoofer array. One J-INFRA subwoofer provides additional very low frequency energy for two J subwoofers.
(Jim Evans)
