Genesis Advanced Technologies 2JR - Manual (Page 19)

Ver 1.0 Sep 2011
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a bs o l u t e f i d e l i t y ®
A second great 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.
The 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 G2jr is about
average for large loudspeakers. At 2m, the G2jr 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. (And for this reason, the
BASS GAIN for the G2jr has a control range of -3dB/+12dB)
Hence, for a listening distance of 5m (about 15ft) the line source
will appear to be more than 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.
As a result the change in loudness of the line source 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 G2jr 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 G2jr has no first
reflection from the floor, ceiling or sidewalls. The net result is that
there are far fewer detail-robbing room reflections from the room
than other types of loudspeakers. With fewer spurious reflections to