A loudspeaker that is placed near a wall, ceiling or floor will usually be amplified in the lower frequencies in a sometimes not desirable way (since it may lead to an indistinct sound recreation).

• 置于靠近墙、天花板或地板的扬声器其低音频率通常会以一种不良的形式被放大（因为它可能导致不明显的声音再现）。