HomeMy WebLinkAboutSP201800003 Study 2018-08-08(C(tSTAGESOUND
AUDIO LIGHTING VIDEO ACOUSTICS
Report: Acoustical Sound Transmission Measurements at the property owned by
John and Carter Bryan
Location: 8115 Dick Woods Road, Afton VA
Date of Measurements: 5/10/18
Equipment Used: Apple iPad Pro 9.7 tablet
Studio Six Digital Audio Tools 10. 14.8 measurement software
Studio Six Digital iPrecisionMic2 reference microphone (SN CQ 10 172)
Cirrus Research 511E 1kHz microphone calibrator (SN 038861)
Tests and Surveys Completed:
1. A visual survey was made of the barn building, the rear porch and field behind the building, and
the general surrounding area on all sides of the building. GPS measurements were made from
the center rear edge of the rear porch of the barn, and the estimated nearest distance to Woods
Road in front of the barn was calculated to be 425' away. The distance to the nearest house (to
the left of the lake) was calculated to be 1300' away.
2. A discussion with Walker Richmond (the Bryan's representative) was held regarding the types of
events and music that would be held at this site, and the conclusion was made to arrange any
loudspeakers or amplification equipment to be facing away from the barn and to be as close to
the barn as possible (25' out from the barn if possible) as to direct all amplified sound away from
the street out front as well as to use the barn itself to block or reflect any excess "unwanted
sound " from reaching the street.
3. Ambient noise measurements were made at several locations along the property line adjacent to
Dick Woods Road out in front of the barn building. Multiple 30 -second average readings were
recorded, and the aggregate average SPL reading was calculated to be 38.5dBA (A -weighted
ambient sound level).
4. With the above information, and using the most conservative estimates possible (ignoring the
sound blocking of the building and assuming that any sound reinforcement system is
omnidirectional), I have calculated the maximum allowable amplified sound level (with the
loudspeakers placed 25' out from the rear porch of the barn building) to be 97dBA at a distance
of lm in front of the loudspeaker (if 2 or more loudspeakers are used, reduce this number by
3dBA per loudspeaker).
5. As most professional loudspeaker systems are capable of getting considerably louder than the
above 97dBA level, I strongly encourage you to consider purchasing a set of loudspeakers (and
amplifiers) that have a special design that would provide IOdB of sound rejection from the rear
of the loudspeaker cabinet (to greatly improve the sound rejection back towards the street) as
well as to allow us to "lock down" the system volume so that no matter what the DJ or system
operator tried to do during an event, the sound level would never be able to exceed the pre-
determined maximum sound pressure level. The approximate cost of such a system would be
$14,000, and details can be provided as to how this system would work.
Measurements Taken By:
Brian Taylor, Stage Sound, Inc.
2240 Shenandoah Ave NW, Roanoke, VA 24017
2240 Shenandoah Avenue NW 0 Roanoke, VA 24017 0 www.stagesound.com 0 Phone: 540.342.2040 0 Fax: 540.345.5158 0 installation@stagesound.com