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发表于 2020-7-16 21:29
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来自 上海市浦东新区
我再告诉你一遍,你说的是错的。简单的道理,比如5寸下潜是55hz,一般是指-3db55hz,那么54hz就不响了吗?
50hz不响了吗?
不是,还是会响,只是声压不够高而已.
小房间或者靠墙,都能靠反射混响增加低频声压,达到-3db标准,变相增加下潜.
我的音箱,官方参数-3db38hz,实测能-3db25hz,靠的就是小房间的混响.
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音箱放到墙角能增加低频是不准确的。原理是这样的:当声源靠近硬质表面时,相当于有了一个镜像声源,+6dB,而频率是不会变的。不管如何,频率是不会变的,你记牢。
反射跟混响并不是一码事。
“达到-3dB”并没有你这种说法?
唯一的可能就是,稍高频率的能量增加,你的声级计的带通滤波器阻带抑制效果不够,被算进去成为更低频率的成分了。
你不要跟我争了,我看到你们乱说又要去找资料跟你们科普我也很累的。
One way this can occur in buildings is when a source is placed close to a hard surface
such as a concrete floor or wall. The surface acts like an acoustic mirror and the original
source energy is reflected, as if the source were displaced by a distance d/2 behind the surface
of the mirror. If the distances are small enough and the frequency low enough, the pressure
radiates from the original and reflected source in phase in all directions. When sound level
measurements are made very close to a reflecting surface, a 6 dB increase in level can be
expected due to pressure doubling.
ARCHITECTURAL ACOUSTICS,Marshall Long,Elsevier Academic Press,2006.
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