The vertical axis is the absorption coefficient, which indicates the level of absorption. Zero (0) means that no sound is absorbed, i.e. 100% of all incoming sound towards the material surface is reflected back into the room again. This is typically true for very hard materials. One (1) means that all sound is absorbed in the material, i.e. no sound is reflected back into the room. A value of 0.5 means that 50% of the incoming sound is absorbed (disappears) and 50% is reflected back into the room.
The horizontal axis is the frequency of the sound (HZ). The higher the frequency, the higher the pitch of the sound you hear.
The curve indicates how much sound BAUX Acoustic products absorb for different frequency spans. BAUX Wood Wool is well equipped to absorb human voice frequencies (between 500-4000Hz). NRC (Noise Reduction Coefficient) is an average rating of how much sound an acoustic product can absorb.
The sound graph can be found on specific product pages and in our catalogue for Acoustic Pulp or Acoustic Wood Wool. You can find the catalogue in our Architect Toolkit download section on our website.