Re:An “acoustic metamaterial” that can cancel 94 percent of ...
by georgn on Monday March 11, 2019 @01:49PM
(#19361055)
By all means, read up on bass traps... but be aware that posts about bass traps imply a fundamental misunderstanding of what they do (perhaps I'm misreading).
The problem: a speaker in a room produces sound, that sound is reflects by the walls. Those reflections will vary WRT phase of the original sound and causing something called comb-filtering (some frequencies will be louder because the reflections are in phase and amplify -- others will be 180º out of phase, resulting in a complete cancellation of those frequencies).
Solutions: sound attenuating material at the edges of a room to interfere with the _reflections_ and this reduce or eliminate comb-filtering. The goal is to improve the listening experience _inside_ the room. Acoustic treatment does almost nothing to help your neighbours.
The problem: a speaker in a room produces sound, that sound is reflects by the walls. Those reflections will vary WRT phase of the original sound and causing something called comb-filtering (some frequencies will be louder because the reflections are in phase and amplify -- others will be 180º out of phase, resulting in a complete cancellation of those frequencies).
Solutions: sound attenuating material at the edges of a room to interfere with the _reflections_ and this reduce or eliminate comb-filtering. The goal is to improve the listening experience _inside_ the room. Acoustic treatment does almost nothing to help your neighbours.