acoustical materials

1. ACOUSTICAL
MATERIALS
AHANA CHETHAN
DHATHRI KV
ARPITHA S
PRATEEK JAIN
YOGITHA M

2. • acoustical materials are those materials designed and used
for the purpose of absorbing sound that might otherwise
be reflected.
• An open window is an excellent absorber since the sounds
passing through the open window are not reflected back
but makes a poor sound barrier. Painted concrete block is
a good sound barrier but will reflect about 97% if the
incident sound striking it.

3. SOUND ABSORBENTS
FOAM PANELS
• These acoustical foam sound absorbers are used in a wide variety of
applications ranging from Recording and Broadcast Studios to
Commercial and Industrial Facilities. Available in Polyurethane or in
a Class 1 Fire Rated foam. These products can be applied directly to
walls, hung as baffles or used as freestanding absorbers
• This material is cut into various patterns, shapes and sizes. Thicker
foam will absorb more sound, especially in the lower frequency
ranges.

4. large foam wedges are used in a wide variety of acoustic
applications where maximum absorption is required or low
frequency control is desired. Anechoic chambers are used for
loudspeaker and microphone testing, engine noise analysis,
quieting scientific equipment and machinery or any other
application that requires a room with no sound reflections.
Every square is identical, allowing for seamless appearance on
installation.
Prevent destructive specular reflections.
Eliminate room modes, comb filtering, standing waves and
undesirable specular artifacts.
Attenuate sound pressure build-up in rooms.

5. Hanging Baffles are ideal for manufacturing areas and other
high noise interior environments. Baffles are shipped
assembled and ready to hang with eyelets at each of the four
corners.

6. SOUND ABSORBENTS
TONE TILES
• Tile is a white acoustical wall panel with a soft textured appearance.
• Their easily managable sizes provide installers the flexibility to mount acoustical
panels around existing objects.
• In addition to reducing echo and reverberation, these acoustical panels are used to
create unique designs and patterns.
• The glass fiber core is faced with a paintable covering. This allows you to match or
complement existing wall colors by applying a light coat of flat or matte spray
paint.
• local printing companies now have the capability to produce an image directly to
the face of these panels.

8. SOUND ABSORBENTS
FABRIC WRAPPED PANELS
• These panels are manufactured from a rigid high density glass fiber
acoustical board and covered with an acoustically transparent fabric. The
edges on these decorative wall panels are chemically hardened and offer
several edge design choices.
• These absorbers are suitable for all applications including offices,
recording, broadcast, worship facilities, museums, auditoriums, theaters
ETC
• sound panels also make a great alternative to fabric stretch wall systems.
These sound control panels look as good as they sound

10. ACOUSTIC WALL COVERING
• Acoustical wall fabric is a dimensional fabric that offers excellent
acoustical properties, unmatched fade resistance, and a fire/smoke
retardant Class A rating.
• Is resistant to moisture, mildew, rot, bacteria, and is non-allergenic.
• Produced with no VOC’s (volatile organic compounds), ODS’s (ozone
depleting substances), heavy metals or formaldehyde, it's the perfect
acoustic fabric for offices, classrooms, conference centers or any area
where speech intelligibility is a critical factor.

12. SOUND ABSORBRNTS
BAFFLE AND BANNERS
• Baffles are an economical way to reduce sound pressure levels and lower reverberation times
in large spaces such as gymnasiums, theaters, restaurants, health and fitness clubs, etc.
• Reverberation times can be lowered from a RT60 of 4 - 9 seconds down to a RT60 of 0.5 - 2
seconds.
• Speech intelligibility is greatly improved and sound intensity levels can be simultaneously
reduced by 3 to 12 decibels.
• These baffles are easily suspended from existing open truss and pre-engineered suspension
systems. They are designed to hang in a vertical fashion, allowing free flow of air and
integrate exceptionally well with existing sprinklers, lighting and HVAC systems.

14. POROUS MATERIALS
• Examples of porous materials :
Glass fiber
 Mineral wool Mineral wool
Open or partially open cell foams
• SOUND PROPAGATION IS Two phases: Solid (frame) and gas (air)

16. Helmholtz resonance
• Helmholtz resonance or wind throb is the phenomenon of air resonance in a cavity, such as
when one blows across the top of an empty bottle
• There are many kinds of cause, both natural and volitional. There are many kinds of transduction
process that convert energy from some other form into sonic energy, producing a sound wave. There is one
fundamental equation that describes sound wave propagation, the acoustic wave equation, but the
phenomena that emerge from it are varied and often complex. The wave carries energy throughout the
propagating medium. Eventually this energy is transduced again into other forms, in ways that again may
be natural and/or volitionally contrived. The final effect may be purely physical or it may reach far into
the biological or volitional domains