These have reduced air volume behind part of the sound absorbing wall of the TubeTrap in exchange for increased air volume being located behind the rest of the surface area of the TubeTrap. Part of the trap breaths less deeply while the rest of the trap breaths more deeply.
These reduced air volume behind part of the sound absorbing wall of the TubeTrap, in exchange for an acoustic resonator being introduced into the remaining volume of air inside the Bass Traps. Part of the trap breaths less deeply while the rest of the trap breaths much more deeply at some particular frequency
This design has adjustable Helmholtz bass traps. The elements of the acoustic circuit inside the TubeTrap can be adjusted by the owner or setup technician so that the response of the trap exactly matches the resonance response of the room and location in the room that the trap is being located in.
This model has low frequency resonant traps that are used to change the shape of major mode resonances or standing waves in rooms. They are not used for absorbing bass but for moving the sound cancel zone away from the middle of the room, towards the back end wall of the room. They have very large resonator pipes and volumes with a slight damping factor added so they die out quickly enough to not be heard.