Absorbers
Absorbers; Melamine Foam, Polyurethane Foam, Low Density Fiberglass Batt, and High-Density Fiberglass Board are used in the room to absorb reflective energy where walls and ceilings create acoustical mirrors. Absorbers keep noise from reflecting from surfaces in a room and returning to the listening position as a delayed signal causing inaccurate noise levels. Absorption will lower the volume in the room to some degree because reflective noise is reduced therefore volume is reduced.
Diffusers and Reflectors
Diffusers and reflectors; Barrel/Pyramid are used to reshape reflective energy where walls and ceilings create acoustical mirrors. Diffusers and reflectors keep volume the same as untreated walls and ceilings while changing the shape of the noise. Diffusers and reflectors break up the sound wave patterns to eliminate spikes and dips in frequencies at the listening position.
Sealers
Sealers; Door Seals, Automatic Door Bottoms, Thresholds, and Acoustical Caulk are used to close gaps in openings, such as doors & windows and penetrations, such as outlets, switch boxes, HVAC openings, and anywhere building materials meet. Sealers are very cost effective yet often the most overlooked step in noise control solutions.
Isolation and Vibration Control
Isolation and vibration control; Pad Type Mountings, Resilient Sound Isolation Clips, Isolation Mountings, Resilient Channels, Damping Compound, and
are used to eliminate structure borne noise where materials meet or vibrate. Isolators and vibration control materials keep noise from traveling through materials such as pipes, ducts, studs, drywall, plywood, concrete, glass or sheet metal.
Barriers
Barriers; Non-Reinforced Flexible Vinyl, Reinforced Flexible Barrier, Barrier/Absorber Blankets, and Barrier/Absorber Composites are used to keep noise from transmitting from one space to another. Noise barriers are always high density, massive, heavy materials. Flexible barriers work better because they "flex" with sound pressure. Rigid barriers such as drywall, concrete, plywood and like materials need to be isolated to keep them from transmitting noise structurally. Barriers are essential for eliminating noise transmission.