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a bs o l u t e f i d e l i t y
floor or the ceiling. No deleterious interference from these surfaces
is created (as in virtually all other kinds of speakers).
Another advantage of the line source is that the vertical spectral
content of music is virtually the same throughout the length of the
line source. Hence, the seating height does not matter with this
speaker; unlike point source speakers where it is important for the
ears to be aligned in relationship with the tweeter.
A third important advantage of a line source is that it attenuates at
–3dB with a doubling of distance whereas a point source
attenuates at –6dB with a doubling of distance.
For example, with a sensitivity of 91dB/watt at 1m, the Genesis 2 is
about average for large loudspeakers. At 2m, the G2 line source
can deliver 89dB/watt, at 4m 86dB/watt, and at 8m 83dB/watt. For
the equivalent point source loudspeaker, it will be 85dB/watt at 2m,
79dB/watt at 4m, and 73dB/watt at 8m. Hence, for a listening
distance of 4m (about 12ft) the line source will appear to be almost
twice as loud as a point source loudspeaker. This is the great
advantage that a line source loudspeaker will have over a point
source loudspeaker in a large room – particularly when the seating
distance is over 4m from the loudspeaker.
The second great advantage of the line source over the point
source is that the change in loudness is much less over a small
change in distance. Hence, it results in a much larger sweet spot
as small side to side changes in seating position result in less of a
sonic change than with the point source loudspeaker.
The Genesis 2.2 is also a dipole radiator. The midrange and
tweeter drivers are mounted on a rigid acrylic panel with no
enclosure. This has two advantages: firstly, it eliminates any
enclosure or boxy colorations caused by cabinet vibrations or
resonance.
Secondly, the dipole creates a cardioid radiation pattern (like a
figure-eight), which has its maximum output at the listening position
and behind the speaker itself, and minimum output to the sides in
the plane of the loudspeakers. This very effectively minimizes the
bounce from the sidewalls.
Hence, in conjunction with the line source, the G2.2 has no first
reflection from the floor, ceiling or sidewalls. The net result is that
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