The below is from Genelec at genelec.com:
Subwoofer Configuration & Positioning
HOW AND WHERE TO PLACE
By positioning the subwoofer close to a wall, it's radiation efficiency
can be maximized and simultaneously adverse room effects
minimised. Placed on the wall, the effective subwoofer output will
double and any interference dips in the frequency response are
eliminated. Genelec subwoofers have been designed so that they
may also be recessed flush into the wall whilst allowing access to the
amplifier connections and controls.
Due to their omnidirectional dispersion, the subwoofers may be
positioned free standing with the ports and the amplifier facing the
wall. Then, great care must be taken to ensure that interferences with
any nearby walls do not deteriorate the frequency response.
HOW ABOUT SURROUND SOUND REPRODUCTION?
Due to the versatile 3 channel input to the crossover filters, both
stereo and three channel L/C/R (left, centre, right) surround systems
may be easily configured. The Genelec subwoofers with the Genelec
Two Way Systems will produce the ultimate surround sound system:
easy to install and balance, accurate in reproduction, and full of
dynamic power.
End Genelec.com text
Note that placement against the wall is recommended above, so that you
can take advantage of the half-space 3dB gain in sub output. Placement
in a corner would be a quarter-space, and the corner makes a nice horn
which is the basis of the corner Klipschorn design.
Bonnie *:>
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