TEMPLATE DESIGN 2007 www.PosterPresentations.com Sound
Reflectors and the Projection of Sound Kaegan Gregory Joseph Kim
Rockdale Magnet School for Science and Technology Introduction
Background Information Methods Data Analysis Data
Analysis/Conclusion Literature Cited Acknowledgements Fold or cut
poster here The graph above shows the differences in balance by
showing the average standard deviations. The graph also shows that
the plastic reflector had the lowest differences in balance meaning
that it was the closest to the ideal balance which is a difference
of 0. Acoustic spaces (concert halls, auditoriums, theaters) are
often acoustically unbalanced. In order to achieve optimum
listening quality of music, acoustic adjustments must be
individually made for auditoriums, including acoustic shells and
sound reflectors. Since sound shells are expensive, unwieldy, and
not really feasible for this project, sound reflectors will be used
because they are relatively inexpensive, and easily made. The
reflectors made for this project were scale to suit a fairly small
amplifier that projects sound into the auditorium. However, through
the use of sound localization in this scaled model, a larger set of
reflectors can be built for performance ensembles that also
corrects the auditoriums acoustics. A performance center that is
used for an orchestral performance should have 1.9 seconds of
resonance, or the time it takes for a sound to dissipate (Long,
2006). To achieve this, the natural acoustics of a space must be
edited using plasters, changing the shape of the hall, or by using
on stage mechanisms for balance. Another problem with performance
halls is that they have spots in which they are acoustically
unbalanced, have low resonance, or are otherwise acoustically dead.
Many acoustical engineers address these issues by implementing the
acoustic tools known as sound reflectors (Precision fabrics group
Inc., 2012). Key concepts in this project were the optimum
reverberation of sound, the identification of acoustically
undesirable places in the hall (Long, 2006), and the localization
of frequencies (Chen et al., 2003). Reverberation of sound is
important because it creates a certain color to the sound that
otherwise is lost. The identification of acoustically undesirable
places in a hall was extraordinarily important to this project,
because it will be at those locations that frequency levels will be
tested. The localization of frequencies is the testing of different
frequency levels, and will be how balance is tested in a hall.
Citation Na, Y., Lancaster, J., Casali, J., & Cho, G. (2007).
Sound absorption coefficients of micro-fiber fabrics by
reverberation room method. Textile Research Journal, 77 (5),
330-335. Retrieved from
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Bocox, J. C., Hasselwander, G. B., Hargis, J. M., & Ford, J. S.
(2002). The inside story. Civil Engineering, 72 (7), 56-61.
Retrieved from
http://search.proquest.com/docview/228497050?accountid=50 132
Moffat, A. S. (1989). New graphics program debuts in concert hall.
Science, 245 (4925), 1452-1452. Retrieved from
http://search.proquest.com/docview/213535009?accountid=50 132 I
would like to thank the following people for their help in the
process of performing this experiment. Mr. Scott Bolen for
assisting in the research and construction of the sound reflectors.
Mr. Christopher Coleman for allowing the researchers to use the
auditorium. The Magnet School fund for providing necessary
supplies. From the overall experimentation, it was observed by the
researchers that the plastic reflectors balanced the acoustics of
the auditorium better than the wood reflectors did. This is the
case because the plastic reflectors reflected the different
pitches, while the wood reflectors absorbed more of the sound.
There was not a real trend in the frequencies with the reflectors
of the different locations in the auditorium tested whether in the
front, middle, or back row or stage left, stage right, or center
stage because of how the auditorium was designed and because of how
the reflectors were placed. The raw acoustics however, showed a
trend in the frequencies because there were no reflectors. With the
reflectors, in terms of balance, the trend was going on and off
possibly because of how the reflectors were placed. The overall
goal was to balance the acoustics in the auditorium, and that was
mostly achieved. Acoustics in an auditorium are extremely variable,
and though the inferential statistics showed that no one reflector
was significantly better, it was shown that all reflectors were
significantly better than an auditorium without reflectors. This is
just testament to the great craftsmanship of all reflectors rather
than just one good set.. The acoustics of the auditorium will be
tested without the sound panels. The control was to test the
auditorium by projecting frequencies from the amplifier with no
acoustical treatments applied. Create the sound reflection panels
Create 4, 2 legged stands Create 4, 3x2 panels from ply wood Screw
the panels to the stands Create 4 more stands Cut 6, 3 foot and 6,
2 foot strips of ply wood Create 3, 3x2 frames from them Staple 3,
3x2 section of construction sheeting to the frames Use sound level
meter and composition software to test for different positions and
materials to find optimum acoustic position Materials Plytanium 1/4
x 4 x 8 Pine Sanded Plywood Blue Hawk 10-ft x 100-ft Construction
Film Sound Level Meter Auditorium Speaker Ableton Live 8.2.2 (or
other composition software) These graphs represent balance created
by the sound reflectors. They are shown on a standard X and Y axis.
The graph with the lowest bars created the best balance, therefore,
it can be said that the plastic reflectors were much more effective
in balancing the auditorium. Wood reflectors position 1 Wood
reflectors position 2 Plastic reflectors position 2 Close up of
Plastic reflectors position 2 Plastic Reflectors Position 1
Revisions: