声音的产生当你拨动琴弦的时候,你会看见琴弦在快速地来回振动;一旦振动停止了,声音也消失了。没错儿,声音就是振动产生的。例如敲击大鼓,鼓皮急速下陷,紧贴鼓皮的空气填补空位,使附近的空气变稀薄,密度减小。这里的空气变稀疏,成为“疏”的部分。在紧接着的下一瞬间,具有弹性的鼓皮急速回弹,向外隆起,压缩附近的空气,密度增大。这里的空气变浓密,成为“密”的部分。大鼓的鼓皮每次下陷和隆起都会使附近的空气变“疏”和变 Sounds When you dial the strings, you see the strings vibrating back and forth quickly; once the vibration stops, the sound disappears. No problem, the sound is vibration. For example, percussion bass drum, drum skin rapid subsidence, close to the skin of the air to fill the vacancy, the nearby air thinning, reducing density. The air here becomes sparse, becoming “sparse” part. Immediately after the next moment, the resilient drum skin rapidly rebounds, bulging outward, compressing nearby air and increasing density. The air here is thicker and becomes the “secret” part. Drum drum skin every time the subsidence and uplift will make the air around the “sparse ” and change