The biggest reason for boommy bass is that your amplifier is unable to control the woofer movement properly due to poor damping. The best fix is to bump up the impedance of the speakers using a device named autoformer. It essentially multiply the impedance by a factor of 2, 2.75, 3, 4, 8 and so on. Depending on your nominal speaker impedance, the resultant dampling factor will do from under-damped (loose bass) to over damped (dry sound). The optimal setting simply means the system is critically damped and it should give you the best result.
All other fixes that I've tried -- tube trap, RPG skyline, RPG diffusor, cables, drapery, spikes, Aurios --- work marginally at best.
All other fixes that I've tried -- tube trap, RPG skyline, RPG diffusor, cables, drapery, spikes, Aurios --- work marginally at best.