Interesting Audio Illusions
Gareth Magennis
particularly striking. (must wear headphones though)
Gareth.
Alan
wrote:
> Check out these audio illusions. The Binaural Head recording is
> particularly striking. (must wear headphones though)
>
>
> Gareth.
Thanks for this Gareth really interesting.
daz.diamond
misleading - e.g. 4 Scale illusion : 'Two major scales are played: one
ascending, one descending' - the advertised effect is of the _same_
scale being played from opposite directions, not different scales, and
the score images even show this on the site ... and afaikt no 2 Phantom
words : 'overlapping sequences of repeating words or phrases, located in
different regions of stereo space' - a loop panned hard left and right
but delayed in one channel - seems a little ambiguous to me ... besides,
I'm not sure these theoretical examples using e.g. pure sine waves, with
no attack or decay, or other changes in dynamic between 'notes' reflect
much relevance to the way we hear the sounds and noises that constitute
our daily lives. Maybe it would work better if the assertions about what
will happen to the listener weren't such a strong suggestion - both me
and my partner experienced different effects to the ones described,
maybe due to the language, maybe not - either way it wasn't _that_ helpful.
anyway, enough pedantry already - shoot me down :)
daz
Gareth Magennis
"daz.diamond" <sp...@spam.com> wrote in message
news:6Vbwj.36520$os2....@newsfe3-win.ntli.net...
I too found the scale descriptions a little confusing, due to the inherent
ambiguity. It perhaps may have been clearer to say that actually 2 scales
are not being played at all - the right ear hears an ascending and
descending sequence, the left hears a similar one, yet the brain
reconstructs this into 2 distinct scales that aren't really there. (The
ambiguity being that you could also state that there are actually 2 scales
playing, but they have been panned around, and the brain ignores the
panning).
I was intereseted to read that left handed people perceived the panning
differently. I hear the first high C in my right ear and the first low one
in my left, and suspect this obvious cue determines my perception of the
descending scale right, ascending left. Why would left handers do things
differently?
I would also suspect that musical people do things differently to non
musical. I get a very clear visualisation of the right hand playing one
scale and the left playing another, but thats because I was trained as a
pianist. Surely. I don't know how non musical people visualise scales.
Sorry for a little more pedantry!
Gareth.
daz.diamond
> ambiguity. It perhaps may have been clearer to say that actually 2 scales
> are not being played at all - the right ear hears an ascending and
> descending sequence, the left hears a similar one, yet the brain
> reconstructs this into 2 distinct scales that aren't really there. (The
> ambiguity being that you could also state that there are actually 2 scales
> playing, but they have been panned around, and the brain ignores the
> panning).
and I get the impression [maybe its just me] that the author maybe
thinks that only sound from the right speaker is heard in the right ear,
and so on - on at least one listen, I experienced the notes panning
between 5 positions l, lc, c rc, r, which maybe due to the metrics of my
head, thickness of bones, spacing of eardrums etc let alone any further
perceptual effects going on
> I would also suspect that musical people do things differently to non
> musical. I get a very clear visualisation of the right hand playing one
> scale and the left playing another, but thats because I was trained as a
> pianist. Surely. I don't know how non musical people visualise scales.
the phenomenon of synæsthesia - a weird one to everyday joe, but a given
to most half-decent musicians, right ?
daz
Gareth Magennis
I guess so. When I was younger I used to have Perfect Pitch - now I am
often fooled by tones. But anyway, I still find that music in different
keys has a different feel. The key of C has a very round, open, innocent
feel to it, quite possibly because this is the first key I learned to play a
piano in, and has been associated with childhood innocence etc. D has a
bold, kind of military feel to it, F is very warming, like a friendy smile.
To me, playing a classical piece in a different key completely changes the
whole feeling of it - maybe this is why those old dead composers chose the
keys they did.
Yes, I'm sure musicians have a lot of concious or subconcious associations
between sounds and other senses, its that translating music into emotions
thing they do so well. The best thing is they are able somehow to convey
this to their less musical audience . Which is nice.
Gareth.
William Sommerwerck
go "tick tick", not "tick tock". If anyone would like a description (I don't
know the psychacoustic reason), I'd be happy to to give it.
daz.diamond
hickery dickery tick ... doesn't it depend on the mechanism :?
philicorda
Wouldn't this depend on the type of escapement?
A recoil escapement should sound different to a Graham escapement for
example, and have an audible change between the 'tick' and the 'tock'.
William Sommerwerck
wrote in message news:83gwj.456$Z_2...@newsfe4-win.ntli.net...
> On Sun, 24 Feb 2008 07:11:24 -0800, William Sommerwerck wrote:
>> I'm probably the only person in the world who's aware that clocks
>> actually go "tick tick", not "tick tock". If anyone would like a
>> description (I don't know the psychacoustic reason), I'd be happy
>> to give it.
> Wouldn't this depend on the type of escapement?
> A recoil escapement should sound different to a Graham escapement for
> example, and have an audible change between the 'tick' and the 'tock'.
The thought has crossed my mind; you and daz.diamond might be right. Listen
to this and see what you think.
Back in 1980 I attended the SCES and heard a demo from Peter Moncrief which
purported to show the audibility of absolute phase by playing a 0.5 Hz
square wave through an LS3/5a. There was an obvious difference in timbre
between the B110 going in and coming out.
When I got back home, I attempted to duplicate the experiment, using Audio
Technica electret headphones. (They were selected not only for their
quality, but because their step-up transformers were electrically isolated,
making it easy to reverse polarity.) A Heathkit generator provided the 0.5Hz
square wave.
In the process of experimentation I discovered that the square wave _always_
sounded like "tick tock". Always. I attached a 'scope and confirmed that the
polarity didn't matter -- the first pulse I heard had a different timbre
from the second.
Using the 'scope to show the polarity, I found I could mentally "flop" the
"tick" and "tock", and the inversion was stable with time. It was sort of
the audio equivalent of the Necker Cube.
Although some escapements might very well "sound different", this isn't
required to hear "tick tock". The ear & brain seem to do it by themselves.
daz.diamond
> sounded like "tick tock". Always. I attached a 'scope and confirmed that the
> polarity didn't matter -- the first pulse I heard had a different timbre
> from the second.
>
> Using the 'scope to show the polarity, I found I could mentally "flop" the
> "tick" and "tock", and the inversion was stable with time. It was sort of
> the audio equivalent of the Necker Cube.
>
> Although some escapements might very well "sound different", this isn't
> required to hear "tick tock". The ear & brain seem to do it by themselves.
>
any ideas as to why this may be ?
is it something to do with modulated blood pressure in the ears / brain
- the body naturally _expects_ [and therefore perceives] a difference
in phase from 2 or more consequtive pulses [as normally provided by the
heart] ???
- most interesting, I'm gonna try your experiment later ...
William Sommerwerck
>> In the process of experimentation I discovered that the square wave
_always_
>> sounded like "tick tock". Always. I attached a 'scope and confirmed that
the
>> polarity didn't matter -- the first pulse I heard had a different timbre
>> from the second.
>> Using the 'scope to show the polarity, I found I could mentally "flop"
the
>> "tick" and "tock", and the inversion was stable with time. It was sort of
>> the audio equivalent of the Necker Cube.
>> Although some escapements might very well "sound different", this isn't
>> required to hear "tick tock". The ear & brain seem to do it by
themselves.
> any ideas as to why this may be?
None.
> is it something to do with modulated blood pressure in the ears / brain
> - the body naturally _expects_ [and therefore perceives] a difference
> in phase from 2 or more consequtive pulses [as normally provided by the
> heart] ???
> - most interesting, I'm gonna try your experiment later ...
Please let us know what you find out...
Ron Capik
>
> < .......snip.. >
>
> In the process of experimentation I discovered that the square wave _always_
> sounded like "tick tock". Always. I attached a 'scope and confirmed that the
> polarity didn't matter -- the first pulse I heard had a different timbre
> from the second.
>
> Using the 'scope to show the polarity, I found I could mentally "flop" the
> "tick" and "tock", and the inversion was stable with time. It was sort of
> the audio equivalent of the Necker Cube.
>
> Although some escapements might very well "sound different", this isn't
> required to hear "tick tock". The ear & brain seem to do it by themselves.
One of my groups had a similar discussion about left or right brain
dominance. The url below has an optical illusion of a spinning dancer.
Conjecture is that the direction first perceived relates to brain dominance.
< http://delicategeniusblog.com/?p=552 >
Training seems to have a large impact on perceptions. From my experience
playing an instrument had a large effect on my musical perceptions. Studies
have also shown that your native language (and perhaps dialect) also has
an effect on musical perception for things like dissonance.
[YMMV]
Later...
Ron Capik
--
Gareth Magennis
"Ron Capik" <r.c...@worldnet.att.net> wrote in message
news:47C1CAED...@worldnet.att.net...
> William Sommerwerck wrote:
>
>>
>> < .......snip.. >
>>
>> In the process of experimentation I discovered that the square wave
>> _always_
>> sounded like "tick tock". Always. I attached a 'scope and confirmed that
>> the
>> polarity didn't matter -- the first pulse I heard had a different timbre
>> from the second.
>>
>> Using the 'scope to show the polarity, I found I could mentally "flop"
>> the
>> "tick" and "tock", and the inversion was stable with time. It was sort of
>> the audio equivalent of the Necker Cube.
>>
>> Although some escapements might very well "sound different", this isn't
>> required to hear "tick tock". The ear & brain seem to do it by
>> themselves.
>
> One of my groups had a similar discussion about left or right brain
> dominance. The url below has an optical illusion of a spinning dancer.
> Conjecture is that the direction first perceived relates to brain
> dominance.
>
> < http://delicategeniusblog.com/?p=552 >
>
This fellow disagrees with the left/right brain explanation:
http://www.michaelbach.de/ot/sze_silhouette/index.html
There is rather a neat collection of other optical illusions on his page
though:
http://www.michaelbach.de/ot/
Gareth.
daz.diamond
>
>
Nothing conclusive yet, that's what !!
I can switch sides of a basic rythm fairly easily, and am used to a
metronomic 120 bpm [and therefore 60 bpm ], and did feel some notion of
up, down, up, down, but then, the 'flipping of the beat' goes against :
<snip>
> There was an obvious difference in timbre between the B110 going in
> and coming out.
</snip>
Is that not just some kind of bad speaker design that makes a speaker
sound different when it moved in each direction ...
I put the wav files and a few response links on my website, and a few
notes in my blog. do the mini survey here :
http://daz.roughdiamondproductions.com/2008/02/24/65
If y'all want to have a listen and click a few links we'll find out if
we're all mad or whether its just me and william ...
I really should get out more :)