Acoustic Room Treatment is mostly referred to treating echo and reflections in a room.  But building a acoustically treated room cannot be done without blocking external sounds and noise.

We grouped this products as NOISE CONTROL products, such as Soundabsorption products and Sound Blocking products, such as Mass Loaded Vinyl, soundproof panels, soundproof wall covers and so on.

Soundproofing and acoustic room treatment require different approach and different products.

NOISE CONTROL Products.  Noise Control Products are products that reduce the sound pressure level (also referred to as “NOISE”) by absorbing sound energy. Sound absorption materials do not reflect sound waves m but rather absorb them as a sponge. Good example of sound absorption material is Acoustic blanket Producer’s choice. As sound reaches the blanket it is not reflected, but instead goes through the blanket and spends its energy on vibrating the fibers of inside the blanket. The energy is converted into small amounts of heat. Sound Absorption products have to be porous so the sound can get in, such as foam, fibers, porous stone etc.
Noise Control Products are used to cancel sound reflections and echo.  Efficiency of different materials at sound absorption is measured by using a single value number, known as NRC = Noise reduction coefficient.  NRC 1.0 means 100% sound absorption.  NRC 0.8 means 80% Sound absorption.
Factors that affect Sound Absorption efficacy of a material:  Thickness, Density, Porosity.

SOUND BLOCKING Products.  Sound Blocking Products are products that stop the sound from going through it.   Sound Blocking material reflect the sound, instead of absorbing it. The sound bounces off the soundblocking barrier kind of like a tennis ball bounces off a wall.  Sound Blocking materials do not reduce sound energy, but rather work as a barrier on the way of a sound wave.  This process is known as Sound Transmission Loss.  (STL) Sound blocking Products are used to stop sound from going from one room to another.  Sound Blocking material are usually solid, like brick, steel, concrete wall.
SoundBlocking efficiency of different materials is measured by using a single number coefficient, STC = Sound Transmission Class.  STC 33 means 33dB sound transmission loss.
Factors that affect Sound Blocking efficacy of a material:  Mass.