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The myth of "harmful" early reflections - Klaus Rampelmann


Major Contributor
Forum Donor
Feb 5, 2020
Oxford, England
I've just found this interesting piece revising existing literature on the treatment of early reflection areas titled "The myth of "harmful" early reflections" (attached).

I haven't read it yet because it's in German (which I can't read) and I've been "cleaning up" the Google translation (attached), but the author it seems firmly stationed on the Toole side of the argument.

The myth of "harmful" early reflections
Klaus Rampelmann

If you read online discussion forums, audio magazines and manufacturers' websites,
the constant message that early reflections of the first order are fundamental
are bad and must be eliminated or reduced in level, either by strategic
Positioning of speakers and listening position (Theiss 1996b), through acoustic treatment
(Völker 1998, Völker 1999), or by using loudspeakers with high directivity or
by Dipolen (Linkwitz 2007). Often there are listening conditions in studio control rooms
(Keyword: reflection-free zone) or standards or recommendations such as SSF-01 2002
referred to where reflections should be 10 dB quieter than that within the first 15 ms
Direct sound.


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Addicted to Fun and Learning
Forum Donor
Apr 22, 2016
Princeton, Texas
Mind you the author is not an acoustics guy himself, but a diligent literature researcher with sometimes a bit of bias in the literature he chooses.
I had an extensive conversation with Klaus on the topic of early reflections on another forum. He has an enormous amount of information on the topic and is capable of disagreeing without being disagreeable, which was most welcome, because we disagreed a lot. He taught me a few things which I was not aware of, but neither of us changed the other's mind about whether early reflections are generally a net benefit or a net detriment.
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