Why Acoustic Panels Don’t Block Noise

Echo Control vs Transmission Loss

Isolating one room’s noise from the next is a common soundproofing goal.   Noise bleeding through a common wall, ceiling or floor surface will threaten the privacy of each room and lower the level of confidentiality.   When working to protect room B from room A’s noise levels, care must be given to applying proper techniques for sound isolation.

Sound panels that are wall or ceiling mounted inside a room are there for a purpose. And that purpose is to capture and convert echoes from the interior of that room.   Think of a loud restaurant, for example. The echoes will bounce off all the hard perimeter surfaces in the dining area, forcing table top conversation to elevate. The resulting strain in conversation begins to compete with the ambient background noise, which in turn, combines to raise the decibel levels even further.   But when sound panels are introduced into the room, those echoes are captured and converted.   This reduces the level of background noise, restores the restaurant to premium sound quality, and affords the dining patrons to relax and converse in normal conversational tones.   Sound panels reduce echo.

What sound panels do NOT do is block noise that will bleed through perimeter wall, ceiling or flooring surfaces.   Sound waves that radiate throughout a room will spread like a pebble wave in a pond, traveling at speeds in excess of 760 miles per hour.   Once those sound waves hit the perimeter surface, a portion of that energy will pass structurally through the common surface, to become air borne in the next room over.   Essentially, the framing inside a wall, floor or ceiling assembly is connecting rooms together, and allowing the structural vibrations to pass noise back and forth between rooms much like a string pulled tight between two cans.   The energy transfer is not blocked by the sound panel, the sound panel is there to only reduce the energy that attempts to reflect back into the room.   Sound panels make room A less loud, the room where the original noise is generated in, but do not make room B less loud, which is the room the noise is filtering into.

Sound panels in today’s marketplace are typically made of either melamine foam or compressed fiberglass.   In either case, these panels offer excellent absorption coefficients for capturing and converting excessive noise levels inside a room.   But their intended purpose is NOT to protect adjoining spaces from noise that wants to leak next door.   With one exception.   There is a hybrid sound panel that serves a dual purpose, which is to both “block” the noise from bleeding through the wall it is attached to, and “absorb” the echoes that would otherwise rebound off the wall and return to the room in the form of echo. This hybrid product layers a thin dense membrane between two layers of compressed fiberglass and gets wrapped in 60 different cloth colors to serve as a finished wall sound panel.   With this panel system, the coverage needs to be 100% of the common wall you seek to protect against noise bleed.   This product is called a FabricBloc Panel and can be found online at https://www.controlnoise.com/product/fabricbloc-panels/

What does block noise is density.   Rather than anchoring a set of standard sound panels to a common surface and expecting any kind of transmission loss, there are layering techniques that you can apply to a finished common wall, ceiling or flooring surface that will combat sound bleed and knock up to 90% of the transmitting noise out.   The messaging with this blog is to help you understand that it is NOT the sound panels you see all over the internet that can perform the room isolation you are seeking, but instead, a layering system using Mass Loaded Vinyl that can layer up to the surface and help deaden the transmission of sound.   For more information on combating your sound bleed issues, reach back to NetWell Noise Control’s help desk at 1-800-638-9355.

The bottom line, do not buy sound panels to block noise.   Buy sound panels to absorb echo.