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Those of you who believe measurements aren't the whole story, do you have a hypothesis why that is?

Wes

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Interesting assertion - what is the malleability of selection on a morphological structure as opposed to neural connections or coding?

I would not make a claim either way.
 

Blumlein 88

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Interesting assertion - what is the malleability of selection on a morphological structure as opposed to neural connections or coding?

I would not make a claim either way.
I must say this is a darn good question. My initial thought immediately illicited other considerations that matter to the point I think perhaps there is no definitive answer in either direction. Perhaps just instances of one direction vs another for what is selected.

Reading about how humans can/do read leaves you with the impression that parts of our brain were selected for other reasons, but a new coding/combination of those regions just fit together nicely to let us communicate via reading/writing. The coding was malleable enough the morphological structure didn't need to be.
 

Wes

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it's good that no one could see your thoughts illiciting...

of course, the flyin the oinkment is that processing in vertebrate neural systems involves changes in 'morphology' as connections lapse and are grown
 

Kal Rubinson

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it's good that no one could see your thoughts illiciting...

of course, the flyin the oinkment is that processing in vertebrate neural systems involves changes in 'morphology' as connections lapse and are grown
and have modulated efficacies.
 

aslan7

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Mine was pretty reliable as long as I kept to a regimen of cleaning the pins and removing any film from the surface of the mercury. My real problem was (is?) that I cannot keep my hands off stuff and tried to make unwise and un correctable modifications.
Yup. Moved to an SME III with Shure and Ortofon integrated wands which I still have. As for Thorens but that's in parts, too. :facepalm:
If I remember correctly Monk recommended cleaning the pins by gently scraping the ends with the end of a wooden matchstick. Now that’s high tech. But despite all that aggravation I enjoyed the tone arm.
 

LarryRS

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Those of you who believe measurements aren't the whole story, do you have a hypothesis why that is?

Our brain.

of course, the flyin the oinkment is that processing in vertebrate neural systems involves changes in 'morphology' as connections lapse and are grown

Um, no. Neural plasticity may or many not involve the formation and retraction of connections. There are many more mechanisms involved in synaptic transmission than the number of connections present. For instance, increasing the signal through an inhibitory synapse in proximity to an excitatory synapse will modulate the effect of the excitatory signal with no change in the number of connections. There are other inter- and intracellular mechanisms that obtain that can affect neuronal signal processing in both the long and short term.
 

Kal Rubinson

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Neural plasticity may or many not involve the formation and retraction of connections. There are many more mechanisms involved in synaptic transmission than the number of connections present. For instance, increasing the signal through an inhibitory synapse in proximity to an excitatory synapse will modulate the effect of the excitatory signal with no change in the number of connections. There are other inter- and intracellular mechanisms that obtain that can affect neuronal signal processing in both the long and short term.
As noted, in brief, above.
 

Wes

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Neural connections lapse, so I hop that is not controversial.

Some decades ago, Fernando Nottebohm (at Rockefeller) showed that they also form in adult birds. That has since been extended to humans and othe rmammals.

I hardly claimed that this was the only mechanism affecting processing, nor am I wedded to the connectionist paradigm, even in in AI.
 

Head_Unit

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It is not generally apparent from measurements which horns have "horn coloration" and which ones do not.
This is a good example of where measurements fall short to this day. An interesting possible start was an article by Newell and Holland in the 8/94 issue of Speaker Builder, "Round the Horn" wherein they applied cepstral analysis to...well I think of it as looking at delayed energy coming out of the horn. But in an echo-ish way, maybe not the same as a waterfall plot? "Reflecting on Echoes and the Cepstrum: A Look at Quefrency Alanysis and Hearing" at http://www.libinst.com/cepst.htm discusses some of this.

Then there was some work by Earl Geddes, seeming to indicate that our sensitivity to distortion is not absolute but could vary with SPL. Well, why not? But that has not been the conventional idea.

Now as an engineer I'm pretty much a measurements guy, but even those are decreasing. I haven't seen anyone do a DAC staircase in eons, or the HF riding extreme LF to modulate the audible signal through all the DAC levels, or noise floor modulation.
 

LarryRS

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"of course, the flyin the oinkment is that processing in vertebrate neural systems involves changes in 'morphology' as connections lapse and are grown"

Nottebohm and countless others notwithstanding, the above statement would leave those not versed in the neurosciences with the impression that synaptic remodeling is a/the predominant mechanism in neural processing. I'm not even willing any longer to advocate that synaptic proliferation and pruning is a dominant mechanism in vertebrate neural development. Since early on, however, it has been a mechanism that has proven accessible for study, given the early methodolgical developments and studies of people like Golgi and Ramon y Cajal that pointed us toward investigations of the physiological meaning of changes in neuronal morphology and studies of model systems like the squid giant synapse that allowed for investigation of the physiological sequelae of learning on synaptic function.

While I would't argue that formation and elimination of neuronal connections is unimportant, especially in a developmental context, it may be reasonable to argue that it's primacy in our thinking about neural processing is in no small part due to it's accessibility for study.

"Then there was some work by Earl Geddes, seeming to indicate that our sensitivity to distortion is not absolute but could vary with SPL. Well, why not? But that has not been the conventional idea.

Now as an engineer I'm pretty much a measurements guy, but even those are decreasing."

Very well stated. We have come an incredibly long way with the sophistication of our measurements. But much less far in terms of understanding our perception and appreciation of the way music is presented by audio equipment and its physical setting.
 

Wes

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"of course, the flyin the oinkment is that processing in vertebrate neural systems involves changes in 'morphology' as connections lapse and are grown"

Nottebohm and countless others notwithstanding, the above statement would leave those not versed in the neurosciences with the impression that synaptic remodeling is a/the predominant mechanism in neural processing. I'm not even willing any longer to advocate that synaptic proliferation and pruning is a dominant mechanism in vertebrate neural development. Since early on, however, it has been a mechanism that has proven accessible for study, given the early methodolgical developments and studies of people like Golgi and Ramon y Cajal that pointed us toward investigations of the physiological meaning of changes in neuronal morphology and studies of model systems like the squid giant synapse that allowed for investigation of the physiological sequelae of learning on synaptic function.

While I would't argue that formation and elimination of neuronal connections is unimportant, especially in a developmental context, it may be reasonable to argue that it's primacy in our thinking about neural processing is in no small part due to it's accessibility for study.

"Then there was some work by Earl Geddes, seeming to indicate that our sensitivity to distortion is not absolute but could vary with SPL. Well, why not? But that has not been the conventional idea.

Now as an engineer I'm pretty much a measurements guy, but even those are decreasing."

Very well stated. We have come an incredibly long way with the sophistication of our measurements. But much less far in terms of understanding our perception and appreciation of the way music is presented by audio equipment and its physical setting.

no, if it was, i'd say so
 

audio2design

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For instance, all of the listener-generated in-room preference curves include a dip at about 8 kHz, followed by a rise at about 12 kHz. Why is that? I'm not expecting you to answer - it's a rhetorical question, pointing out an example of what I consider to be "non-intuitive-ness".

Interestingly enough, the transverse resonant frequency of gypsum board (drywall) is ~ 22300/4 - 22300/2 dependent on the stud spacing or about 5.6Khz-11Khz for . I believe 16" was traditionally the most common for walls which is about 9Khz with 24 pretty common on interior studs. Ceiling joists (same as floors) are typically 16". If you can find a table with absorption coefficients for typical materials out to 20KHz (I have one somewhere, but can't find it), it is not uncommon for the absorption to increase as the frequency increases to a point, then start to drop again. Couple that with high frequency attenuation with distances that include reflection compared to a more typical near field production setting and there are a lot of clues as to why that could be the preferred curve.

I think the issue with using intuitive is what is black magic to someone without the relevant knowledge may be quite intuitive to explain for someone with the correct knowledge, though, sans seeing the experimental data, they may have been as oblivious as anyone else.
 

Duke

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Interestingly enough, the transverse resonant frequency of gypsum board (drywall) is ~ 22300/4 - 22300/2 dependent on the stud spacing or about 5.6Khz-11Khz for . I believe 16" was traditionally the most common for walls which is about 9Khz with 24 pretty common on interior studs. Ceiling joists (same as floors) are typically 16". If you can find a table with absorption coefficients for typical materials out to 20KHz (I have one somewhere, but can't find it), it is not uncommon for the absorption to increase as the frequency increases to a point, then start to drop again. Couple that with high frequency attenuation with distances that include reflection compared to a more typical near field production setting and there are a lot of clues as to why that could be the preferred curve.


I must admit that this explanation is not intuitive to me.

I think the issue with using intuitive is what is black magic to someone without the relevant knowledge may be quite intuitive to explain for someone with the correct knowledge, though, sans seeing the experimental data, they may have been as oblivious as anyone else.


Imo there is a big gap between what may not be "intuitive" and what constitutes "black magic."
 
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