Kurt Hamster wrote:
On Wed, 17 Nov 2004 22:45:20 +0000, Ian Molton used
to say...


Kurt Hamster wrote:

On Wed, 17 Nov 2004 22:28:15 +0000, Ian Molton used
to say...



IOW, the ear introduces the same distortion all the time, so introducing
more distortion wont help.


Why won't it help? Ever heard of noise cancellation technology?

Yes I have - but thats about cancelling *unwanted* noise.

If distortion isn't noise then what is it?

micks claim was that there have been measurements with a sensor in the
inner ear showing that the ear itself distorts sound. thats not noise,
however since its part of our perceptual systems. Im reluctant to say
the brain compensates for it, but it will clearly expect the distortion
caused by the ears mechanisms to be present.

the distortion applied by your ears is present even when you hear the
music *live*, first hand.

The ears don't apply any distortion. YOu really don't understand
psycho-acoustics do you?

I wasnt talking about psychoacoustics. neither was micks only point
about psychoacoustics.

Im not going to argue this further with you [Kurt] as you have been
misrepresenting what I've said each time in your replies. this is the
last comment from me on this subject (in reply to you).

mick - if you wish to continue discussing this Im happy to respond to you.

On Wed, 17 Nov 2004 23:35:44 +0000, Ian Molton wrote:

snip

mick - if you wish to continue discussing this Im happy to respond to you.

Cheers, Ian.

This is all just playing with ideas. I don't profess to be an expert on
hearing, recording or amplification or anything remotely connected with
them! Somebody, somewhere *must* have written books on this stuff, but I
probably wouldn't understand them... grin

I can see where you are coming from: "If listening to a live performance,
for the sake of argument, from a point source instrument, our 'inherent
distortion' is the only thing impacting on the signal."

But our ears don't perceive an instrument as a point source. We hear
positional information - possibly phase and/or frequency shift sensing -
which must include reflected sound and, possibly, THD inherrent in any
frequency shift detection. There are no point source sounds that we can
detect in isolation - except maybe in an anechoical chamber!

Even stereo point sources with perfect reproduction *may* be insufficient
to reproduce all the necessary information as much of it must be at very
low level (where it could be detectable with logarithmic hearing but not
with linear amplification - the source information would be lost at the
microphone).

"If we now make a recording of the signal, again, for the sake of argument,
with a perfect microphone, and played it back from a single speaker in
place of the musician, with a perfect speaker, we should expect the
speaker to produce the same waveform as the musical instrument."

You are quite right - providing that the listener is comparing a point
source live instrument to an isolated single driver speaker in an anechoic
chamber. Another perfect microphone at the original listener's location
should give an exact copy of the source (although if you used a human
listener he/she should only have one ear, with the outer bit (pinnae? not
sure...) cut off!).

In real life we would be producing a point-source representation of the
original, with all the location information stripped from it. It would
measure perfectly, but information would be missing. It would be analagous
to a painting, which is a 2D represdentation of a 3D space.

"If we can agree on the above, this suggests that in order to hear
something that is true to the original sound, we need to have distortion
free reproduction."

IMHO that doesn't necessarily follow. Unless you can be sure of recreating
*all* reflected sound from the original source's surroundings the
infinitely low distortion of a perfect reproduction system will still be
missing information.

I just have a hunch that the THD produced by a valve amp is doing more
than just giving a "warm" and "easy" feeling to the sound. I am wondering
if it is fooling the ear/brain combination in some way. That deception is
translated by some people into a feeling that the sound is more lifelike,
giving rise to their almost unanimous descriptions. This could be going
further than simple addition of even harmonics being used to "fill out"
musical sound to make it feel "bigger".

I don't know. Someone must have done, or be doing, research on this.

--
Mick
(no M$ software on here... :-) )
Web: http://www.nascom.info
Web: http://projectedsound.tk

"mick" wrote in message
news

This is all just playing with ideas.

It's worse than that, its mangling ideas with bad logic.

I don't profess to be an expert
on hearing, recording or amplification or anything remotely connected
with them! Somebody, somewhere *must* have written books on this
stuff, but I probably wouldn't understand them... grin

First study up on basic logic. This seems to be lacking from your ideas.

I can see where you are coming from: "If listening to a live
performance, for the sake of argument, from a point source
instrument, our 'inherent distortion' is the only thing impacting on
the signal."

No, the words "point source" are gratuitous, and an obvious attempt to
introduce either a straw man or a red herring.

Do try to think logically and do try to stay on topic.

Arny Krueger wrote:

No, the words "point source" are gratuitous, and an obvious attempt to
introduce either a straw man or a red herring.

Do try to think logically and do try to stay on topic.

To be fair, the point source was originally introduced by me.

mick wrote:
On Wed, 17 Nov 2004 23:35:44 +0000, Ian Molton wrote:

snip

mick - if you wish to continue discussing this Im happy to respond to you.


Cheers, Ian.

Np. Im happy to natter when things are kept civil.

But our ears don't perceive an instrument as a point source. We hear
positional information

Nothing about a point source says it cant be somewher eother than
directly in front of you (although I had assumed that in my previous
example)

Even stereo point sources with perfect reproduction *may* be insufficient
to reproduce all the necessary information as much of it must be at very
low level

I dont think the level matters. But I agree that a stereo speaker setup
wont be able to reproduce a given scenario as it was originally, even in
a perfect room.

You are quite right - providing that the listener is comparing a point
source live instrument to an isolated single driver speaker in an anechoic
chamber. Another perfect microphone at the original listener's location
should give an exact copy of the source (although if you used a human
listener he/she should only have one ear, with the outer bit (pinnae? not
sure...) cut off!).

I think your logic is flawed there. the human wouldnt need to cut off
their outer ear.

I just have a hunch that the THD produced by a valve amp is doing more
than just giving a "warm" and "easy" feeling to the sound. I am wondering
if it is fooling the ear/brain combination in some way. That deception is
translated by some people into a feeling that the sound is more lifelike,
giving rise to their almost unanimous descriptions. This could be going
further than simple addition of even harmonics being used to "fill out"
musical sound to make it feel "bigger".

Its not *im*possible, but I dont think that adding information is
inherently better than simply accurately reproducing the original.

I don't know. Someone must have done, or be doing, research on this.

Probably.

In article , mick
wrote:
On Wed, 17 Nov 2004 23:35:44 +0000, Ian Molton wrote:

snip

mick - if you wish to continue discussing this Im happy to respond to
you.

Cheers, Ian.

This is all just playing with ideas. I don't profess to be an expert on
hearing, recording or amplification or anything remotely connected with
them! Somebody, somewhere *must* have written books on this stuff, but I
probably wouldn't understand them... grin

I can see where you are coming from: "If listening to a live
performance, for the sake of argument, from a point source instrument,
our 'inherent distortion' is the only thing impacting on the signal."

I am not sure what the "point source" aspect has with to do with
nonlinearities.

But our ears don't perceive an instrument as a point source. We hear
positional information - possibly phase and/or frequency shift sensing -
which must include reflected sound and, possibly, THD inherrent in any
frequency shift detection. There are no point source sounds that we can
detect in isolation - except maybe in an anechoical chamber!

A change in frequency response is not the same thing as distortion. They
are different in kind.

Nonlinear distortion can/will create frequencies that were not in the
orginal signal, and which may not be at simple integer harmonics of the
frequencies that were present. Consider intermodulation distortion as a
simple example of this process. In such cases nonlinearity produces effects
that you won't get as a result of room acoustics or the departures from
flat response of something like an amp or speaker.


Even stereo point sources with perfect reproduction *may* be
insufficient to reproduce all the necessary information as much of it
must be at very low level (where it could be detectable with logarithmic
hearing but not with linear amplification - the source information would
be lost at the microphone).

Not clear what the comment about "detectable with logarithmic hearing
but not with linear amplification" means. Nor about the "source
information".


In real life we would be producing a point-source representation of the
original, with all the location information stripped from it. It would
measure perfectly, but information would be missing. It would be
analagous to a painting, which is a 2D represdentation of a 3D space.

Real sound sources are not normally "point sources". Easy enough to
establish this by measuring the sound radiated from something like cello as
a function of direction and distance.


I just have a hunch that the THD produced by a valve amp is doing more
than just giving a "warm" and "easy" feeling to the sound. I am
wondering if it is fooling the ear/brain combination in some way.

That might be so. But the above comments do not all relate to what you say
here.


I don't know. Someone must have done, or be doing, research on this.

It would be nice to think so, but I've not yet found any that seems
reliable to me. Interested to hear references to some...

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/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

In article , Ian Molton
wrote:
Kurt Hamster wrote:


The ears don't apply any distortion. YOu really don't understand
psycho-acoustics do you?

I wasnt talking about psychoacoustics. neither was micks only point
about psychoacoustics.

I can't comment on the psychology area, but the physiological processes in
the ear involve various forms of nonlinear response. However I'd say we
have to take care with calling this 'distortion' as it is probably better
considered as something like conversion or processing.

However IIUC your point correctly, Ian, it was that you were saying that
this happens in the hearing process, not in the sound as it is produced and
propagated. Hence if it is not externally applied when we listen to live
music, then it becomes debatable if we want equipment to apply a process
which our head will be performing anyway. (Thus applying it twice in
sucession, which would not occur for the live sounds.)

Snag being to try and equate or compare such 'external' and internal
processes, or make assumptions about what may do to the other. Not easy, as
we don't seem to really understand the implications of either process...

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/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

Jim Lesurf wrote:

I can't comment on the psychology area, but the physiological processes in
the ear involve various forms of nonlinear response. However I'd say we
have to take care with calling this 'distortion' as it is probably better
considered as something like conversion or processing.

Agreed. I was trying to stick with the language mick used (and finding
it somewhat difficult to convey my meaning in the process) (no offense,
mick)

However IIUC your point correctly, Ian, it was that you were saying that
this happens in the hearing process, not in the sound as it is produced and
propagated.

Correct.

Hence if it is not externally applied when we listen to live
music, then it becomes debatable if we want equipment to apply a process
which our head will be performing anyway. (Thus applying it twice in
sucession, which would not occur for the live sounds.)

Yup. IMO.

Snag being to try and equate or compare such 'external' and internal
processes, or make assumptions about what may do to the other. Not easy, as
we don't seem to really understand the implications of either process...

And few people would allow one to attach a sensor directly to the nerves
in the ear...

Sadly, MRI technology which would be able to resolve signals on the
magnitude of nerve-sizes is not quite with us - it requires multi-tesla
strength magnets, and the only such machine in existence apparently has
an apperture just big enough to insert a fly into...