During a recent study (1999-2001) for the National Park Service, the
folks at Wyle Labs and HMMH measured SPLs in box canyons on the floor
of the Grand Canyon at well below 10dBA, Walter. Wanna hear the blood
flow thru your capilaries? I know a few places in the desert
southwest that'll put the anechoic chambers at Harmon Industries
(JBL) to shame.
Bernie
>From: Dan Dugan <>
>
>>
>> Maybe somebody can help this guy out.
>>
>> -Dan Dugan
>>
>>
>>>>From: "Davenny, Ben" <>
>>>>Hello,
>>>>
>>>>Do you have overall A-weighted sound level data (in dBA) corresponding =
to
>>>>various natural soundscapes (like rainforests, beaches, parks, etc.)? =
I'm
>>>>working on a report about acoustics in healthcare facilities, and I'm
>>>>interested in the use of appropriate sound levels of nature sounds to m=
ask
>>>>undesirable noises.
>
>I've measured sound levels all over the place. But I'm not sure I'd say
>there is, for instance, a typical sound level for a beach. Or any other
>type of location. Each site is it's own thing on this.
>
>It is rare to find a site that goes below 20 dBA for a average. Though
>I've measured a few, and short silent times can be much quieter. Typical
>of my nature recording sites where I can get a good recording is 20-40
>dBA on slow averaging on the meter. But, I have no average level for
>such sites.
>
>After all, frogs have been measured at above 125 dBA for their calls.
>And it's frogs I'm recording.
>
>Walt
>
>
>
>
>
>"Microphones are not ears,
>Loudspeakers are not birds,
>A listening room is not nature."
>Klas Strandberg
>Yahoo! Groups Links
>
>
>
>
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Wild Sanctuary, Inc.
P. O. Box 536
Glen Ellen, California 95442-0536
Tel: (707) 996-6677
Fax: (707) 996-0280
http://www.wildsanctuary.com
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