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Positioning the subwoofer in the room
The placement of the subwoofer in the room affects the overall frequency response and sound level of
the system dramatically, as at low frequencies the effects of the room are strong. Even a slight change in
the subwoofer's location can make a marked difference in the frequency balance and often patient and
methodical experimentation and testing is needed to find the optimum placement.
The placement will affect the phase difference between the main loudspeakers and the subwoofer, and
also the bass roll-off rate. These effects can be compensated by the use of the Tone and Phase controls
on the subwoofer; but we recommend that at first you leave the controls untouched and concentrate on
finding the position where the subwoofer gives the smoothest response, and only then use them to fine-
tune the balance and phase alignment between the subwoofer and the main loudspeakers.
To begin, place the subwoofer at the front wall slightly offset from the center. The recommended distance
to the wall is less than 60 cm / 4" measured from the subwoofer's driver. This position gives increased
acoustic loading (and SPL) due to the proximity of the front wall and floor. Cancellations from the front wall
and floor are also avoided. Front wall cancellation for the 85 Hz high pass filtered main loudspeakers can
be eliminated by placing them at least 110 cm / 4" away from the front wall. In a multichannel system the
main loudspeakers should ideally be positioned symmetrically and at an equal distance from the listening
position.
