This problem can now be solved with the HiFonics ZEUS STREET ZST subwoofers in flat design

SPL applications

5 cm bass-midrange driver with a new basket and the 25 mm fabric neodymium tweeter

1 x 2 Ohm Schwingspule

Included BIAS control

ESX QE80.4 DSP Verstärker Koaxial Helix This problem can now beWith the QUANTUM QE DSP series, ESX skillfully combines Class D power with innovative DSP technology. The three amplifiers offer superior sound performance thanks to the integrated DSP processor, which can be optimally adjusted with the included X CONTROL 2 software. This enables an enormous number of setting options and configurations that leave nothing to be desired even for very complex sound systems and self contained factory systems. Features: 4