Re: Complaint about DAB upheld by ASA

In article <87uhk1l7u300g69ltn7a98kopigscvhb1g@xxxxxxx>, Alan White
<alan.lesley@xxxxxxxxxxxxx> wrote:
> On Sun, 09 Oct 2005 09:27:55 +0100, Jim Lesurf <jcgl@xxxxxxxxxxxxxxxxxx>
> wrote:

> >Although if you are interested, you might like to look at the work
> >carried out by Oohashi and others.

[snip]

> This is very interesting.

> I (aged 68) had my hearing tested two years ago and the response was way
> down at 5kHz. In fact my hearing is now so bad that I have to use
> subtitles for TV drama.

Although the most well-known effect of 'age/damage related deafness' is the
loss of high frequencies, there are some less well known effects. These
tend to make it harder to hear 'details' in some complex sounds, and can
have a particular effect on making speech difficult to understand. IIUC
some 'hearing aids' may be able to dynamically modify the response and help
overcome this - although the result may not help with music.

> However, I can still listen to reproduced orchestral music and make a
> fair judgment on the audio quality.

Most of the musical notes from 'acoustic' instruments tend to have the
fundamentals and lower harmonics below a few kHz. And the need to be able
to 'recognise' speech isn't a factor, so I suspect what you describe isn't
unusual, and your speech recogniton problems may be as I describe above.


FWIW some of these things are discussed on the 'hearing' webpages which
are linked from the 'Audio Misc' homepage whose URL is in my sig, below.


> Indeed, I've commented here on the audio quality of some of the Prom
> broadcasts. What I have noticed is that this is far easier for music
> with which I'm familiar (I'm told that I have an excellent musical
> memory) whereas unfamiliar music can become quite difficult and even
> irritating.

That is quite interesting. The human mind tends to use 'cues' from the
senses to produce a 'mental model' and then fit it to the sensory input.
So, in effect, with familiar sounds and patterns we can combine what the
actual sensations are with what our brain is 'producing' as a recognised
pattern. I wonder if the problems I described above prompt the brain to
intensify this and 'fill in' what it misses to keep the perception as
'expected'?...

> As an aside, my 'cocktail party' effect has gone completely and I find
> large gatherings of people in a reverberant environment so irritating
> that I have to leave rather than put up with the 'noise'.

I also have that problem. But TBH I've had it for years. I find
following conversations at a party difficult. Yet I can hear when one of
the violins is out of tune. This is probably also consistent with the
above, I think...

TBH to a large extent, my personal reaction to the 'quality' of something
like DTTV tends to be strongly influenced by the sound. I have always
seemed to be more 'attuned' to sound than vision. This may be because my
eyesight has always been mediocre, and I could not see well for many years.

In my case I spent the first few years at primary school with no glasses,
not realising I needed them. It was when I was 8 years old, I was tested
along with the rest of my class. The nurse asked me "Read the lines on the
chart". I replied "what chart?" :-)

Until I got glasses, I assumed that the reason that good work caused you to
be 'promoted' towards the back of the classroom was that if you were bright
you did not need to see the blackboard so clearly. I assumed that everyone
had the same sight problems as myself... :-)

I suppose this may have been a reason why I became more interested in
music, and then in hifi, than in TV...

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html
.