Some background noise kind of like engine noise, which rising from near-DC and silence to a steady running rate, and then falls again to near-DC and silence with reverberation. This is from an Analog Box circuit created for the purpose. This is intended to give you total onset and turn-off as if switching a mechanism on and off. Unlike the others, this one is not a loop, but the steady portion can be replaced with the <a href="http://freesound.org/people/zimbot/sounds/322054/" rel="nofollow">EngineNoiseSteady</a> sound from this pack (which <em>is</em> a loop), such that if you blend the transitions and repeat the EngineNoiseSteady loop, you can get any desired length. Others built from the same circuit include <a href="http://freesound.org/people/zimbot/sounds/322053/" rel="nofollow">EngineRoomThetaRelaxer</a> and <a href="http://freesound.org/people/zimbot/sounds/322052/" rel="nofollow">EngineRoomWaver</a>, but there are also other sounds intended to fill a similar role but with a rather different character in that same <a href="http://freesound.org/people/zimbot/packs/7572/" rel="nofollow">Backgrounds pack</a>.<br/>EngineRoomOnOff.wav<br/>聲道：2<br/>類型：wav<br/>falling、vessel、ambient、background、rising、engage、abox、disengage、noise、engine、synthetic<br/>落下、船隻、周圍、背景、升起、從事、一個盒子、解開、噪聲、發動機、合成的<br/>資料來源：freesound ( https://freesound.org )