Mener der er lidt brugbar læsning her:
for frequencies below about 700Hz, our sense of hearing measures the phase difference between a sound arriving at each
ear, whereas above this frequency it uses mainly level differences. Out of doors, our ability to determine a sound's direction
remains quite accurate down to remarkably low frequencies, but this ability collapses when listening indoors. Sources
generating low-frequency sounds (below about 100Hz) tend to do so more or less omnidirectionally (the sound wave travels
from the source in all directions) because the wavelength of sound is usually larger than the object itself. When a low-
frequency sound is generated within an enclosed space, the spherical sound waves created will reflect off the boundary
surfaces of the room to arrive back at the ears with a multiplicity of phase variances, due to path-length differences. This
confusion of signals makes it impossible for the ear and brain to extract a reliable phase difference, so normal directional
acuity fails.
So in theory, since you can't tell where the low frequencies are coming from in a room, one subwoofer will be entirely
sufficient. The harmonics of the bass notes will be reproduced by the satellite speakers — which typically start to take over
above about 90Hz — and these will provide plenty of directional information through phase and level differences, in the usual
way. So, although the bass itself is folded down to mono, the impression of stereo imaging is actually preserved perfectly
satisfactorily.
fra http://www.soundonsound.com/sos/apr07/articles/subwoofers.ht m
Spiller selv på samme forstærker & Dali Mentor 6 samt 1 Mentor sub, når jeg kommer i nærheden af det igen skal jeg tjekke
hvilken delefrekvens jeg endte på efter et par eksperimenter..... Det er jo ikke noget større problem at prøve et par
forskellige indstillinger på TDAI'en , og uanset hvad andre kommer op med, kommer du garanteret til "lige at prøve" en
anden variation