Re: 'pressure at the ears' visiting an anechoic chamber

[Jont Allen <jba@xxxxxxxxxxxxxxxx>]

Dear List,
I have been doing some "research" about this pressure effect in the ears,
when you enter the anechoic chamber (AC). I called Cyril Harris, and asked
him for his opinion on this effect. He had to think about it, and didn't
have an answer of the top of his head, but he came up with a reasonable
explanation, I think.

When you have pressure on your ears, there is lots of static (low frequency)
pressure relative to high frequencies. He suggests that when you walk into
the AC, the high frequencies are damped, but not so much for the lows.
Thus the spectral balance is tilted heavily toward the low frequencies.
It is, he argues, the strong low frequency bias towards the low end of
the spectrum that gives the "pressure effect," just as in the case of
normal high frequencies with a static pressure.

What do you think of this explanation?

Jont Allen/Cyril Harris

Nancy Vaughan wrote:
>
> I wonder if this sensation is related in any way to the sensation people
> with binaural hearing loss experience when fitted with a monaural hearing
> aid.  Not routinely, of course, but the ear with a similar hearing loss to
> the aided ear feels is often reported to feel plugged when sound is
> introduced into the opposite ear.  Could the pressure sensation simply be
> related to the absence of sound (at least sound as we are accustomed to
> experiencing it?)
>
> >Malcolm,
> >
> >>>> When visitors enter -for the first time- our (rather large) anechoic
> >>>> chamber, they are always complaining about the strange 'pressure
> >>>> at their ears'. Similar as listening to 'much out of phase' signals in
> >>>...
> >>>
> >>

--
Jont B. Allen, Room E161
AT&T Labs-Research, Shannon Laboratory
180 Park Ave.
Florham Park NJ 07932-0971
973/360-8545voice, x7111fax, http://www.research.att.com/info/jba
To send a fax that I get by email: 973/360-8545 (Experimental)

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