[LINK] Hearing tests for free by phone (o/t)

Bernard Robertson-Dunn brd at iimetro.com.au
Fri Feb 29 17:57:51 EST 2008


stephen at melbpc.org.au wrote:

>  BRD writes:
>
>
> > Ivan Trundle wrote:
> >
> >> And why just a fixed phone? The acoustic ability of my 'fixed'
> >> phone is no better than that of my mobile - or perhaps someone
> >> who knows can tell us what frequency ranges are possible across
> >> both options
> >
> > The frequency response of POTS is about 400 Hz to 3400 Hz.
>
>
>  I'm not sure that the NAL specifically request that people wanting to
>  do an initial screening-test of their hearing use a fixed-line phone,
>  rather than a mobile phone, because of any differing audio frequency
>  responses ..
>
>  (Quote) A mobile phone's audio quality depends on its audio
>  amplifiers' power output and its speakers' impedance.


A mobile phone cannot deliver an audio signal with a wider frequency 
response than the network can provide.

Mobile phones that have an mp3 player might be able to reproduce a 
better audio quality but if the NAL delivers its signal through the POTS 
then the signal will be limited to 400-3.4khz, no matter how good the 
amplifiers at the end are.

Anyway, I don't want what started off as a joke to descend into blind 
criticism of the NAL so I went searching for some more info on the 
tests. It seems that the test does not assess frequency response but 
speech intelligibility. This makes much more sense and looks like a 
credit to the Laboratory.

http://www.hearing.com.au/ViewPage.action?siteNodeId=235&languageId=1&contentId=1129
<quote>

A new version of the highly successful telephone hearing test, Telscreen 
was launched by Minister for Human Services, Senator the Hon. Joe Ludwig 
on Thursday 17 January at Australian Hearing's National Head Office.

Known as Telscreen II, the phone test has been significantly 
re-engineered to provide a more sophisticated test.

"The test uses a computer generated noise that obscures speech for 
people with a hearing loss," said Professor Dillon, Research Director 
for the National Acoustic Laboratories.

"The test that forms Telscreen II is without a doubt, the most advanced 
telephone hearing test in the world and a credit to Australia's ability 
to stay at the forefront of international research," said Minister Ludwig.

Since its launch in 2007, Telscreen has attracted more than 60,000 
callers. The new telephone test, which uses breakthrough technology, 
will make it even easier for the thousands of Australians who suffer 
from a hearing loss to determine whether or not their loss is severe 
enough to seek further treatment.

James Tregonning, client of Australian Hearing Dee Why, was on hand to 
demonstrate the test. "I did the test from home and have since been 
assessed at Australian Hearing. As a result of taking the phone hearing 
test, I have been fitted with hearing aids," he said.

The service can be accessed by the same toll free number. Phone 1800 826 
500 and follow the voice prompts.

</quote>

-- 
 
Regards
brd

Bernard Robertson-Dunn
Sydney Australia
brd at iimetro.com.au




More information about the Link mailing list