Researcher jumps into hi-res discussion and owns hater.

[mmerrill99]

Research into the matter doesn't mean no differences can be discerned longer term. Simply that the fineness of perceptions or in perceiving smallest differences degrades substantially. Not unique to hearing either. You have similar differences related to all your senses. Iconic memory for vision. Haptic memory for touch. From the wikipedia entry on Sensory memory:

 

SM is not involved in higher cognitive functions such as consolidation of memory traces or comparison of information.[18] Likewise, the capacity and duration of SM cannot be influenced by top-down control; a person cannot consciously think or choose what information is stored in SM, or how long it will be stored for.[4] The role of SM is to provide a detailed representation of our entire sensory experience for which relevant pieces of information can be extracted by short-term memory (STM) and processed by working memory (WM).[2] STM is capable of storing information for 10–15 seconds without rehearsal while working memory actively processes, manipulates, and controls the information. Information from STM can then be consolidated into long-term memory where memories can last a lifetime. The transfer of SM to STM is the first step in the Atkinson–Shiffrin memory model which proposes a structure of memory.

 

But it may be that in this area small differences of the type that are only perceivable within the echoic memory timespan, are not that important to our perception of & enjoyment of music? Focus on this type of detail is perhaps the wrong emphasis when it comes to the differences that people report anecdotally - soundstage depth & solidity increasing, air around instruments, better emotional connection to the music/players/singers, etc. Some differences are not conducive to instant A/B differentiation.

[mmerrill99]

There are a number of interesting aspects coming out of this meta-analysis - not that they are new aspects but rather that they re-emphasise what is already established

First this from his conclusion:

" Results showed a small but statistically significant ability of test subjects to discriminate high resolution content, and this effect increased dramatically when test subjects received extensive training"

 

Note the importance of "extensive training". It would be interesting to see just what the statistical result would be if only those studies that engaged in extensive pre-training were included? This is the problem with statistics - a 50% result doesn't necessarily mean that there is no difference - if half the people could hear no difference & half the people could definitely hear a significant difference, the result of this combined would be 50%

I have seen people criticise both of these elements - the small statistical figure & the need for pre-training

 

What these criticisms reveal is an unfamiliarity with perceptual testing & statistical analysis. I don't claim to be an expert in either but I know enough to realise that sensory testing involves testing the perceptions & these are non-exact - so even a fairly obvious differences will be missed some of the time (it may be due to boredom, distraction, second guessing on'e choice, etc.) - the point is that what is being tested is one particular aspect of the workings of a very complex organism & not a machine.

 

I've seen adequate pre-training critiised on the basis that those who claim "night & day differences" should be able to do such a test without pre-training. Again this shows a failure to realise the nature of such tests & the accepted guidelines which recommend adequate training.

 

One other aspect that should be noted - the author states this "One interesting thing that I found, which I did not at all expect, was that most of the potential biases would introduce false negatives. That is, most of the issues were things like not using high res stimuli, or having a filter in the playback chain that removed all high frequency content, or using test methodologies that made it difficult for people to answer correctly even when they heard differences."

 

I actually don't know whey he didn't expect this - it's well known that such tests are biased towards false negatives

[mmerrill99]

You might be quite surprised at what fundamental aspects of a sound humans don't recall accurately within more than about 4 seconds. I'll provide a link or two later to research I linked in another thread.

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Sure but are these "fundamental aspects" of importance to our auditory perception in this hobby where connection to the auditory illusion created by our playback systems? So, are you saying that these "fundamental aspects of sound" that we don;t accurately recall outside our echoic memory timespan, are important "to our perception of & enjoyment of music"?

 

 

We seem to store long-term aspects or features of sound which allows us to immediately identify our family members voices or allows us to immediately recognize & categorise the many different sounds of rain on a roof & differentiate it from the many different sounds of applause or the many different sounds of a crackling fire. What aspects of these sounds we store which allow us this facility to differentiate such diverse spectrum of sound is not fully understood - it is thought that we store some statistical spectrum related to these types of sounds.

[mmerrill99]

Is it important that an audio system play back the correct notes?

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You have switched the discussion from auditory perception to the device accuracy - why?

 

That's the point & why I asked you the question. If you wish to consider this - would a deep understanding of the weightings that auditory perception pays to various aspects of it's analysis/processing of the waveform impinging on the eardrum have any significance to how our audio playback chain is designed?

 

In other words, if perceptual algorithms worked perfectly (some claim they do) would it change your question?

 

The question I would ask is more along the lines of " What aspects of the sound are of importance to our auditory perception & what are the weightings of these aspects"

 

It seems to me that auditory processing is an afterthought in this hobby - the attention is all placed on the technical accuracy of playback when in fact this may well be a focus on the wrong aspects as ultimately it's our flawed auditory perception that makes the judgement about what we are listening to & not some scope or spectrum anayzer

[mmerrill99]

Is it important to you to be able to tell an oboe from a French horn?

 

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It might be considered more productive in a discussion to deal with points in what I posted but .........?

[mmerrill99]

You were asking, as I understood (let me know if I'm wrong) about whether all this echoic memory stuff would really affect the sorts of things audiophiles look for from their systems.

 

Do you think audiophiles want a system that can give them the characteristics that make a saxophone sound more like a live saxophone does, rather than a clarinet, for example? The factors that go into this, as well as such fundamental characteristics as pitch have been the subjects of echoic memory research. (I grant you we would not expect digital audio systems to vary in reproducing the fundamental frequency of a note correctly.)

 

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Well first of all you haven't stated what is "fundamental aspects of a sound humans don't recall accurately within more than about 4 seconds" so until you do this I am not able to ty together your various posts - they just seem random to me.

 

Echoic memory has nothing to do with "Is it important that an audio system play back the correct notes?"

 

Now I think you are suggesting that if listeners don't have a distinct memory of past "notes" outside of the 4 second window of echoic memory then they won't be able to tell the difference between oboe & French horn but correct me if that's not what you are saying. I believe you are saying that pitch is fundamental & accurate memory of it is not retained outside of a 4 sec window & this affects one's ability to differentiate between sax & clarinet. Do you really believe this? I would love to see the research backing up this statement. Or are you saying something like pitch memory is not accurately retained outside of 4 secs & differentiating between different instruments depends on pitch & then drawing an unfounded connection between the two facts?

 

 

It also seems to me that you are mixing up echoic memory and playback accuracy into some sort of amalgam of auditory confusion?

 

I would greatly appreciate links to both your previous research that you said you posted on another thread about these ""fundamental aspects of a sound humans don't recall accurately within more than about 4 seconds" .

[mmerrill99]

You were asking, as I understood (let me know if I'm wrong) about whether all this echoic memory stuff would really affect the sorts of things audiophiles look for from their systems.

I wasn't really asking this - I was suggesting that there's a whole world of other possible factors outside of this focus on echoic memory A/B differences that may well be more important to our judgement of how realistic an illusion is produced by our playback systems. I'm trying to expand people's thinking to consider this.

Do you think audiophiles want a system that can give them the characteristics that make a saxophone sound more like a live saxophone does, rather than a clarinet, for example? The factors that go into this, as well as such fundamental characteristics as pitch have been the subjects of echoic memory research. (I grant you we would not expect digital audio systems to vary in reproducing the fundamental frequency of a note correctly.)

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I believe you might just be taking a very limited view of what "makes a saxophone sound more like a live saxophone" in your statement "The factors that go into this, as well as such fundamental characteristics as pitch have been the subjects of echoic memory research." but if you could be more specific about these factors that make for something sounding "more like live" we could discuss it?

[mmerrill99]

There is echoic memory research regarding many aspects of sound. Among these aspects are pitch (how long is it before our memories of fundamental frequencies begin to deteriorate? what are some things that can actively make those memories less good?) and timbre (what are all the things that distinguish middle C on a piano from the same note on a clarinet or violin?

Ok, thanks for elaborating.

I don't believe our perception of timbre has been fully delineated, as yet, in the research but that doesn't prevent some aspects of it being investigated? Although, how long we retain our memory of timbre may be of some interest, I fail to see what it has to do with the points I'm making?

how long before the accuracy of our recollections of these characteristics begins to deteriorate? what are some things that can actively make those memories less good, or impede the ability to identify the instrument producing the note in the first place?).

Again, if you are making the point that we are not able to judge the difference between an oboe or french horn because of this shortcoming in echoic memory, I would like to see the research papers that back this up. In fact any papers that investigate this aspect (the memory retention of timbre & how it affects our listening) would be of interest as I have never seen this being addressed - it's counter to my experience & I would suggest that of others.

These are only two of the aspects that have been examined in research. Although as I mentioned previously we would not expect our digital audio systems to vary in the fundamental tones they reproduce from a recording (pitch), how many times have you read someone talking about faithful reproduction of timbre ("It sounded like a real piano/saxophone/singer in my room!")? So the various aspects of timbre are directly relevant to what we want from our systems,

Yes, I would agree up to this point - timbre is a very important aspect for a lot of people in their playback systems & often the most important as it defines how realistic a sound they perceive from their playback systems but echoic memory has little to nothing to do with this, IMO

and echoic memory for these aspects is thus directly relevant to our ability to perform comparisons in which echoic memory is involved (most sighted and blind comparisons as currently performed).

I don't know what you are saying here - it seems to me that you are saying that echoic memory is necessary to run tests that involve echoic memory - this would seem to be a self-evident statement?

 

 

I would contend that the majority of comparisons between systems do not involve a <4 second comparison & thus don't involve echoic memory at all. In fact most comparisons done by the common hobbyist are long term listening comparisons

 

What I disagree with is your whole focus on echoic memory & my point that I made already - this may well be the wrong focus for aspects of what we hear as more realism of the playback sound.

 

Edit: I see you edited your original response to my post:

"

You might be quite surprised at what fundamental aspects of a sound humans don't recall accurately within more than about 4 seconds. I'll provide a link or two later to research I linked in another thread.

 

Edit: However, I believe you're onto something regarding "focus on this type of detail."

 

I believed your original post was some counter to my wanting to draw attention to other factors which may be of importance to our auditory perception other than those that are focused on in A/B echoic memory testing but I see now you recognise some value in what I have said? However your subsequent posts have all revolved around the importance of echoic memory!!

[mmerrill99]

It just occurred to me that there may be some confusion here between echoic memory (short & detailed) & sensory memory (longer term & less detailed). What I'm suggesting is that sensory memory & long term memory are actually more important in our judgement of the realism of what we are hearing i.e how much like a "real" saxophone the playback sounds.

 

I consider these aspects much more important than echoic memory (which btw, varies according to the load on working memory). It's our long term memory that we refer to when we recognise voices of our family, rain of a tin roof, oboe vs French horn, etc.

[mmerrill99]

You might call it long term memory, or you might call it something else more accurately.

Ok, I'll bite - what is the more accurate term?

What is it you refer to in order to recognize John Coltrane is playing the same melody sung by Julie Andrews ("My Favorite Things")? The two are in different tempos and keys, one is played by an instrument while one is sung.... Let's say you have never heard the Coltrane before, so there is nothing to remember. How do you recognize it?

Well, now you are getting into a different type of discrimination - the ability to identify a tune by it's rhythm & beat (maybe other factors I've missed?) & categorise it. This is very different to what I'm talking about.

Similarly, you recognize famliy members even when they have a cold, when they are on a low fidelity connection, when they say things you have never heard them say before, or all of these in combination. How can you remember what you have never experienced? So what is it you are actually doing?

No, I don't agree - it's not similar to the extent that it's not a categorization function like the above example, it's a discrimination function.

 

My simplistic understanding of it is that we have a type of stored model - is this an an abstraction of features, a statistical abstraction or some amalgam of the above or something completely different, I don't know, do you? I feel we have a way to go before we reach the level of understanding about the workings of auditory perception as we have about visual perception.

 

AFAIK, visual perception, in simplistic terms, works on the basis of parallel streams of analysis into which signals from the optic nerve are split & these separate analyses brought back together into what we perceive as visual objects.

[mmerrill99]

Here's the link to the research I was talking about: Diana Deutsch - Short Term Memory for Tones

Thanks!

Yes, Diana Deutsch is an interesting researcher in the field of auditory perception.

I looked at the link & although interesting in teasing out one aspect of the working of auditory perception, I don't see it supporting anything which might be understood to mean that echoic memory is a limitation on our normal listening to music. What it actually has a bearing on is the fact that most musical systems already incorporate these limitations - "This type of pattern occurs in many musical cultures –including Western tonal music – and is likely to be well perceived and remembered⁷.

 

This is often the case - composers naturally incorporate a lot of the "factors" of how auditory processing works - "factors" which are only now becoming identified. It is not unusual for composers to have developed an expertise in what works tonally & how to direct the listeners attention between the musical lines in a composition - they have absorbed how auditory perception works & incorporated in their pieces without any formal theory of the underlying working of auditory perception

[mmerrill99]

Please pardon my teasing; one more before I "spill the beans," so to speak.

Look at Miska's comment in this thread, specifically at the last sentence. Think about how this relates to what we've been talking about.

Edit - A couple of other hints:

 

 

Diana Deutsch - Octave Illusion

 

 

 

Diana Deutsch - Tritone Paradox

 

Oh, just "spill the beans" instead of being coy

I've seen & read Deutsch's examples of auditory illusions before - like all illusions they examine & reveal certain aspects of the functioning of auditory processing.

[mmerrill99]

On our normal listening, no. On the ability to make valid listening comparisons - well, if you can't even recall what note was played 4-5 seconds later, what sort of chance do you think you have of being able to compare what you're currently hearing to a 30 second or minute(s) old recollection of the more subtle sorts of factors that go into timbre or soundstage? (Notice this would be the case for blind as well as sighted comparisons.)

 

OK, OK.

What you do when you recognize family members' voices even when you haven't spoken to them in months, they have a cold, are on a bad connection, etc.; the same thing you do when you see the checkerboard pattern that isn't there; the same thing Diana Deutsch's subjects did in the testing described in the two later links I provided; and perhaps most importantly for us, what Miska does when he recognizes the sound signatures of his filters - is pattern matching. We humans are pattern matching motherf__ers. There is a lot of pattern matching we can do better than any machine, as the fact that "captchas" are used for web site security proves every day. The same way we can recognize that distorted shape as the number "2," we recognize the tune in the different tempo and key played by a sax instead of sung is "My Favorite Things."

Pattern matching ability can arise from nature, nurture, or both. In one of Diana Deutsch's illusions, nearly all right-handed folks hear things one way, while *most but not all* left-handed folks hear things another. In our righty-dominated society, some left-handers have become so assimilated via nurture they actually have auditory brain processing more typical of right-handers. If we consider "nurture" as in effect a form of long term training or practice, we see where Miska gets the ability to pattern match the sounds of his filters. Rather than having to rely on attempted memorization to compare filter A to filter B, a futile effort, he knows how filter A is supposed to sound without even having to think about it, so when it is played he can identify it immediately, and the same with filter B. No sensory memory based comparison between the two is necessary.

 

Thus to the extent any audio testing, sighted or blinded, encourages us to rely on memory for comparison between two samples, it's very likely doomed to failure except in very specific exceptional cases. It's only where we've had enough training, practice, experience, whatever you want to call it, to leave memory aside and do pattern matching that we have a greater likelihood of being successful. And this is not just a matter of listening to something a few times to "get it down." Research indicates a long period of daily practice for a week is not enough. And of course, you also need to know what you are listening for, i.e., the pattern you are trying to match. There have been several tests on the forums here (and elsewhere) asking people to compare files to try to select the one with less jitter. No one can hit such a test at a greater than chance rate unless he or she knows what the analog effects of jitter sound like and has long practice or training in identifying those effects, i.e., matching the pattern.

But then does it even matter that one file has more jitter (or analog results of jitter) than another, if we can't identify it in a blind test? Indeed it may. On this last point, if you will forgive me, there is yet more research I can talk about shortly. (Being called to help in the kitchen. )

(Note: The terminology I've seen most often in the research uses the term "sensory memory" for a short term memory store utilized by any of the senses. The names of the stores specific to the senses of hearing and sight are echoic and iconic memory, respectively.)

 

Thank you for this - it's so much better to not have to deal with one-liner enigmatic posts which I actually find very trying.

Frank discussions with both sides making their points is so much better & productive - so glad you abandoned the former approach for this & hope this continues? In fact if you had said all this to start with we could have gotten to the chase a lot sooner than the 10 or more posts it took to get to this simple point

 

I think your use of the phrase "valid listening comparisons" is misleading but I don't think you meant it in the way it reads as you go on to explain that pattern matching is at the heart of most of our listening which I would contend is "valid listening"

Yes, I agree with all you say but pattern matching involves memory retrieval although this is not always a fully conscious activity.

 

It appears that this pattern is not necessarily a fully formed pattern but one that is made up of an abstract series of elements brought together in the moment as a characterisation of the auditory object. These pattern elements are created from birth through life as we are continually exposed to the sounds of the world & how these sounds behave over time (the pattern isn't a static thing - it is a predictive map of how such a sound should "normally" behave)

 

This top down approach is where a pattern & it's predicted behaviour is being continually evaluated against the analysis of the sound being perceived, in real time. When a mismatch occurs between pattern & perceived sound (bottom up signals) a suitable adjustment is made to the pattern that best matches the new behaviour. IMO, a sense of realism is created by our playback system when this pattern matching undergo few if any changes. This is an area of active research & details still have to be worked out.

 

This was my point in my very first post on this thread - what are the pattern matching elements & how are they used by auditory perception to evaluate sound. I must say your reply post to me about all the notes being right is very far from what you are saying here.

[mmerrill99]

Patterns that are matched can involve something that is learned and practiced (to a high degree - as I once heard a sports coach say, "You don't practice until you get it right, you practice until you no longer get it wrong"), or something inborn (the right-handers who hear one of Deutsch's audio illusions one way and the left-handers who hear it another don't do so due to memory), or both (the left-handers who hear it the same way as the right-handers).

 

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I disagree with the inborn bit - all these patterns are the result of exposure to sounds in the world - the more exposure, the more it becomes internalised & a subconscious memory. IMO, this is how we learn grammatical correct use of language - as children we repeat the patterns of sounds we hear (mostly from our parents) & by copying these sound patterns we develop a sense of what sounds "right". Don't know if Chomsky or others have researched this aspect of language acquisition?

 

There is one worrying aspect to this acquisition of sound patterns - if someone is only ever exposed to grammatically incorrect use of language from childhood, it's likely they will find that the wrong grammar "sounds right". To a lesser extent the same applies to music playback systems although I suspect we all have the sound of the natural world as our reference & can recognise when something sounds more realistic.