The Cyber-Spy.Com Usenet Archive Feeds Directly
From The Open And Publicly Available Newsgroup
This Group And Thousands Of Others Are Available
On Most IS NNTP News Servers On Port 119.
Cyber-Spy.Com Is NOT Responsible For Any Topic,
Opinions Or Content Posted To This Or Any Other
Newsgroup. This Web Archive Of The Newsgroup And
Posts Are For Informational Purposes Only.
Subject: Re: Sound cancellation technology?
Date: Sun, 29 Dec 2002 04:03:22 +0000 (UTC)
NNTP-Posting-Date: Sun, 29 Dec 2002 04:03:22 +0000 (UTC)
User-Agent: tin/1.5.14-20020926 ("Soil") (UNIX) (Linux/2.4.19 (i686))
In sci.electronics.design Phil Allison wrote:
> wrote in message
>> In sci.electronics.design Phil Allison wrote:
>> > "Lady Liberty" wrote in message
>> > news:email@example.com...
>> >> How far along has sound cancelation technology come in the last 10
>> >> Can they use it to completely silence a bedroom area for sleeping, yet?
>> > It is still much cheaper to use sound proofing than electronics
>> > and that DOES cover the whole room.
>> Though soundproofing only the ears is cheaper still.
> ** That, unfortunately does NOT work.
> Sound enters the head via the nose and mouth as well as the ear
> canal, also through the bones of the skull.
> Any sound below a few hundred Hz goes around ear plugs like they are
> not there - in fact ear plugs make low frequency sound seem worse since any
> masking effects from mid and highs are gone.
> Been there, done that with 50 Hz tones caused by compressor motors
> bolted onto a common wall.
Earplugs don't have to be passive, and could get a few more db down,
especially if they don't have to cancel HF, which can be mostly killed by
http://inquisitor.i.am/ | mailto:firstname.lastname@example.org | Ian Stirling.
Windows 2000, software for next millenia. - Ian Stirling.
Go Back To The Cyber-Spy.Com
Usenet Web Archive Index Of
The sci.electronics.design Newsgroup