Turbosound ASPECT TA-880 - Manual (Page 42)

user manual
TA-880
TA-880 user manual
Page 42
Bass Enclosure arraying
Aspect bass enclosures are most efficient when ground stacked in a block. Not only do they
benefit from improved coupling when there are no air gaps between them, but they also
couple to the ground. However, some of this energy may be absorbed by nearby obstructions
such as barriers or a tightly-packed standing audience. Sound pressure levels may also be
excessive for members of the audience if they are able to get too close to the enclosures.
When stacking on the stage or on a platform, particularly outdoors, it is preferable to close
the gap between the platform and the floor with sheets of plywood. This results in increased
sound projection into the audience and less leakage backstage.
Aiming - directivity of the stack
The directivity of the bass stack will depend on its dimensions and curvature. A tall thin stack
will disperse a lot in the horizontal plane and become narrow in the vertical plane and
likewise a wide stack will narrow in the horizontal plane. There is usually an optimum
compromise between the two so that a smooth transition can be obtained between the effect
of the coupling of the two stacks down the centre line of the room and the effect of the
individual stacks beaming on their axis. Also adding some curvature to the stack will help to
increase the directivity of the stack especially in the higher frequencies.
Tall, thin bass stacks work best, preferably in blocks of six or eight bins high by two wide.
When space permits use two or three of these blocks, placing the onstage block flush with
and parallel to the stage, with a second and additional identical offstage blocks slightly
separated from the first and angled outwards by 40
°.
Stacking bass cabinets in a line in front of the stage will produce narrower dispersion in the
horizontal plane, while giving wide vertical dispersion.