Editing Loudspeaker (section)

===Placement===
In a typical rectangular listening room, the hard, parallel surfaces of the walls, floor and ceiling cause primary [[acoustic resonance]] nodes in each of the three dimensions: left–right, up–down and forward–backward.<ref>{{cite book |last=Beranek |first=Leo |date=1954 |title=Acoustics |chapter=10 |publisher=McGraw Hill }}</ref> Furthermore, there are more complex resonance modes involving up to all six boundary surfaces combining to create [[standing wave]]s. This is called speaker boundary interference response (SBIR).<ref>{{cite web |url=https://arqen.com/acoustics-101/speaker-placement-boundary-interference/ |title=Is Speaker–Boundary Interference Killing Your Bass? |date=November 11, 2014 |access-date=February 15, 2022 }}</ref> Low frequencies excite these modes the most, since long wavelengths are not much affected by furniture compositions or placement. The mode spacing is critical, especially in small and medium-sized rooms like recording studios, home theaters and broadcast studios. The proximity of the loudspeakers to room boundaries affects how strongly the resonances are excited as well as affecting the relative strength at each frequency. The location of the listener is critical, too, as a position near a boundary can have a great effect on the perceived balance of frequencies. This is because standing-wave patterns are most easily heard in these locations and at lower frequencies, below the [[Schroeder frequency]], depending on room size.{{Citation needed|date=April 2024}}