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• the sound pressure level (SPL) throughout the room is much
more evenly distributed, making it much easier to set the “right”
volume, no matter where the listener is seated.
To achieve this highly desirable line source behavior, it is essential to have a tall
and slim driver. (Simply stacking multiple “cone & dome” high frequency drivers
does not create a proper line source. Instead, it creates a series of point sources
which end up interfering with each other.) With Wisdom Audio’s planar mag-
netic technology, it becomes possible to have drivers that are extremely tall and
slim. In the Insight Series L8i, for example, the active area of the midrange/treble
driver is approximately 1“ wide by 48” tall.
Because of this shape, the sound (even at high frequencies) is distributed uni-
formly across the width of the room from a driver that “looks” only about an
inch wide acoustically. However, the sound is launched in a much more direc-
tional way vertically. By minimizing early reflections from the ceiling and the
floor, the clarity of the system is greatly enhanced. This is heard in both tremen-
dous musical detail and in much-improved dialog intelligibility.
For more detailed information on the loudspeaker drivers in general, and planar
magnetic drivers in particular, please refer to the Planar Magnetic Technology
white paper that can be found on the Wisdom Audio web site, at
www.wisdomaudio.com.
Dynamic woofers
Authoritative, deep bass requires that you move a lot of air. We have chosen to
use dynamic woofers for the bass because they can provide excellent perfor-
mance at lower frequencies.
In order to get comparable bass performance from a planar magnetic design,
you would need to have a huge speaker that would be impractical in most
domestic living spaces. It simply makes more sense to use the best transducer
technology in each area of the reproduced spectrum. One of Wisdom Audio’s
strengths is in seamlessly blending these technologies — particularly important
given the high standards set by our planar magnetic drivers.
Extraordinary drivers
Of course, the dynamic woofers themselves must be rather extraordinary in
order to “keep up” with the planar magnetic drivers right up to the crossover
frequency.
Our woofers are different because they must be in order to do their job. Spe-
cifically, we need highly dynamic, uncompressed bass (to keep up with the
planar magnetic drivers) that does not depend on a critical amount of enclosure
volume (since these speakers are mounted in your wall, and use the space inside
the wall as their “enclosure”). These two design goals require rather extraordi-
nary attention to myriad details.
The motor and suspension system of these woofers therefore includes all the
critical damping required for optimal operation. (In most speakers, the woofers
depend on the air trapped inside their enclosures as an additional “spring” to
help them behave properly.) Technically, this approach is known as an “infinite
baffle” design. In practice, the volume of air behind the speaker does not have
to be infinite, of course. It just needs to be large enough to not act like an acous-
tic “spring.” Recommended and minimum enclosure volumes for the speaker are
listed in the Specifications section, and repeated on the Dimensions page.
