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Topic: If it sounds like a duck and walks like a duck…

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Posted by drdna on 12-07-2008
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After seeing the variation in the sound of the TU-X1 to the quality of electricity, and thinking about recent discussions about the Direct Heated Triode, I would like to start a compendium of anecdotal observations of the idiosyncratic nature of component placements in the circuit. If we can make a large group of observations, we would have the potential to analyze the physical properties of the discrete components to uncover what types of noise and signal effects are important.

I hope all our members here will contribute some observations.

Posted by drdna on 12-07-2008
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 thorsten wrote:
Designers like Kondo San spend many hundred hours "voicing" their Amplifiers, allowing a blending of a variety of colorations together in such a way that the overall sonic impact is quite small. For many others (amateur or professional alike) such extended working is not an option and hence circuits with a strong character and inherent substantial sonic problems are best avoided.
Here is an example of what I mean. Thorsten's excellent article discusses exhaustively several DHT circuit topologies and their various benefits and disadvantages. It is an excellent article, and there is no question in my mind that he is absolutely correct in his perspective; a good deal of attention must be paid to circuit topology. However, he opens the door with statements like the above quote, where it becomes clear that there is a lot more "fine tuning by ear" that must be done, when all the mathematics is over. This is what I hope to explore. Here is the unknown territory, where others have walked, but much like people crawling in a cave with no flashlight, and no maps have been made systematically.

Posted by Romy the Cat on 12-07-2008
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 drdna wrote:
After seeing the variation in the sound of the TU-X1 to the quality of electricity, and thinking about recent discussions about the Direct Heated Triode, I would like to start a compendium of anecdotal observations of the idiosyncratic nature of component placements in the circuit. If we can make a large group of observations, we would have the potential to analyze the physical properties of the discrete components to uncover what types of noise and signal effects are important.

I hope all our members here will contribute some observations.

Hm, I have very many doubts about success of this direction. Surly all passive components in the circuit have influence but I see a desire to catalog and to organize them as some kind of freakish self-serving objective. But is my general attitude toward voicing, if one search the site with word “voicing” then it would be well understood.

I think instead of looking at the generic anecdotal observations that have no references to objectives of observer, to the location of element in circuit and the way HOW this specific element was used it has more since to look at the performance of the very specific elements in context of very specific audio element or circuit. This gives a certain framework and a certain frame of references. I for instance would like to hear what people might say about Sound (or more precisely to say “the sounds” and I feel passive elements operate at First Listening level on my Listening Scale) of a coupling capacitor between first and second stage of Yamamoto’s AD1 amp, or the differences in OPT’s core in some kind of Shindo amp, or sonic differences using a different type of cartridge loading resistor with Aesthetix phonostage, or the need a quality cap between the TU-X1’s detector and decoder.  My interests on all of it are much applied and very specific..

I might be interesting to hear from different people their list of recommended passive elements they prefer to use in different locations, and we have seen it a lot including from me. However, I do not think that it has a lot of practical meaning for others. I would admit that my “list” is not something that strictly my discovery but it was very much influenced by others, still I always question my own observations and conclusions, so how much value would be in the conclusions of others.

As far as “analyze the physical properties of the discrete components to uncover what types …are important”. Well, I do not know. We do not do the discrete components, we use whatever is there. How much values would be if we recognized that tubes with filaments made from thoriated tungsten do not suffers from cathode poisoning? So, what will we do, to covert the oxide cathode to tungsten and to build in our home thoriating bathtubs? I do not think so.

Well, I do not know what I am saying. I need to degree with someone this morning and you were the first one…

The Cat

Posted by drdna on 12-07-2008
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 Romy the Cat wrote:
 drdna wrote:
I would like to start a compendium of anecdotal observations of the idiosyncratic nature of COMPONENT PLACEMENTS in the circuit.
Surely all passive components in the circuit have influence, but I think instead of looking at the generic anecdotal observations that have no references to the location of element in circuit and HOW this specific element was used it has more since to look at the performance of the very specific elements in context of very specific audio element or circuit. This gives a certain framework and a certain frame of references. I for instance would like to hear what people might say about Sound (or more precisely to say “the sounds” and I feel passive elements operate at First Listening level on my Listening Scale) of a coupling capacitor between first and second stage of Yamamoto’s AD1 amp, or the differences in OPT’s core in some kind of Shindo amp, or sonic differences using a different type of cartridge loading resistor with Aesthetix phonostage, or the need a quality cap between the TU-X1’s detector and decoder. My interests on all of it are much applied and very specific..

Yes, this is a fine example. I should have given examples. Naturally, the information is only of use if we know the application. I am more willing to ignore the idea of an objective, since nobody except us here approaches sound this way. It is usually just try it and see if it's "better." But, I am willing to take whatever information I can get and try to sort it all out later.

So, my example is this: in a simple two-stage cascaded DHT design, between a 6SN7 and 2A3, the type of coupling capacitor makes a significant difference in the sound. Compared with polypropylene, polystyrene, and teflon capacitors, using paper-in-oil copper foil capacitors improved resolution and musical sounds of attack and decay, for overall improved dynamics. Grain in the midrange was reduced, allowing the sounds to be presented in a more relaxed way in a deeper soundstage, facilitating more emotional involvement. The use of different capacitors is important in this position.

 Romy the Cat wrote:
Take an element, or the collection of the elements, that do NOT indicate any expressiveness in their own. Then place them into a topological application and you receive Sound. As the result, the only you specific topology will be fully responsible for the Sound, BUT the actions and efforts of the given components. I can give many examples but for instance the aforementioned Cube 950 has no own expressiveness and completely neutral in all application where I ever used it. As far as I concern if the Cube 950 was used and something does not sound correct then the problems are somewhere else or in the topological application.
Agreed, which is why I say it must be in the context of the application. Imagine this: you have a Ford F-150 and Honda Civic. For driving to local record store, both are fine: no difference. But then, for moving washer and dryer, suddenly F-150 works much better. AND then, with only $10 for gas money for a long trip, suddenly Honda Civic works and Ford completely does not.

The different physical characteristics of the components reveals something about the specific application. It is not enough that both F-150 and Civic are both auto with four wheels and engine, any more than Cube 950 and MIT are both capacitors.

We can look at differences in specific applications to begin to understand properties of circuit that are important but which we have been ignoring in a systematic way so far.

 Romy the Cat wrote:
I might be interesting to hear from different people their list of recommended passive elements they prefer to use in different locations, and we have seen it a lot including from me.
Well, that is why I started this thread: we have a bunch of smart people here; we should try to put our heads together on this. The knowledge we may get can be important and powerful to topological design choices.

Adrian

Posted by Paul S on 12-07-2008
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Well, I thought there was a lot of this going on all along, but that we just haven't come up with much that is "universal" in the usual, "what do you recommend?" sense yet?  Maybe this is because one person's Cu PIO is another person's V-Cap, depending on any number of non-standardize-able features of the circuits, ancillary components, system, room, listener, etc.  As an offhand example, I wonder if the Cu PIO coupler would "work just as well" in the same circuit but with a 300B instead of a 2A3?  I realize this does not squib the general idea - at all - but it does seem to significantly temper -and severally restrict - applicability of information within such a "database".  And maybe this is why forums like this tend to fragment into "sections" that address more-specific (and putatively better-defined) issues?

As somewhat of a romantic, I also wonder if what we need is already "out there", spread out here and among the various OCD sites, like some wild, gigantic, Hegel-overshadowing "Encyclopedia of Hi-Fi"?  Shades of Jorge Borges!

I think I have made broad recommendations for amorphous core transformers, because I have yet to hear a downside in any application I am familiar with.  OTOH, at the same time I hope that people would not immediately extend this "recommendation" to PS use, or even dedicated LF, for that matter.  In other words, I hope people do bring to bear their own established objectives and they are paying attention.

Making a small effort, I can't at this time think think of anything else I would make such broad generalizations about.  In fact, sad to say, I realize I am much more comfortable finding fault with and generally slamming components.  But this stems from my continued frustration with components that are either ill conceived, poorly executed in terms of production, or both, which I think of as serious compromises even as I wind up using them, anyway.  I mean, what are you gonna do?  I do try to report my findings, but how are we going to format and subsequently interpret such observations?

Probably, most people who read this site have ignored all the warnings and they are still hovering, waiting for Romy to drop some crumbs that they expect to feast on.  Too bad that just about anything and everything of value herein is - as it has been clearly explained, over and over, ad nauseum - totally dependent on the foreknowledge and the objectives underlying the inquiry.

So, again, any thoughts on just how better to compile and use such a "raw" database?  No surprise, I suppose, but I'm drawing a blank.

Best regards,
Paul S

Posted by drdna on 12-07-2008
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 Paul S wrote:
Well, I thought there was a lot of this going on all along, but that we just haven't come up with much that is "universal"
Yes, my thought is that there is NOTHING universal, but that these choices must be observed in CONTEXT of topology to be useful. An example:

 Paul S wrote:
As an offhand example, I wonder if the Cu PIO coupler would "work just as well" in the same circuit but with a 300B instead of a 2A3?
Yes, this is a good example. Maybe it DOESN'T, and we have that in our "library." Then suddenly we have something POWERFUL! We can think: what is the physical and electrical difference between the 2A3 and 300B and what is the physical and electrical difference between the PIO and the Teflon cap. From this we can begin to extract some useful ideas about the needs of topology for proper function.

I am going back to the car analogy: the Honda Civic and the Ford F-150. Initially we just classified them by the properties: wheels (yes/no), and engine (yes/no). So they seemed the same for a drive to the store. Then we added a new topology: a long distance trip, which only the Civic could do, so we discover a new property: gas mileage (high/low). And we formulate a hypothesis: for long distance trips, a high gas mileage car should be used.

In audio, we might say something like: (just an example) in DHT circuits, a capacitor with lower inductance should be used. Then we can begin to think why this would be the case.

 Paul S wrote:
And maybe this is why forums like this tend to fragment into "sections" that address more-specific (and putatively better-defined)
I think it is actually because it is done in a non-systematic way, without much thought given to figure out the scientific basis of observations.

 Paul S wrote:
As somewhat of a romantic, I also wonder if what we need is already "out there", spread out here and among the various OCD sites, like some wild, gigantic "Encyclopedia of Hi-Fi"? Shades of Jorge Borges!
I am sure it is, but it can only be used if it is compiled coherently in one place.

 Paul S wrote:
So, again, any thoughts on just how better to compile and use such a "raw" database?
Well, just as I said above. I would hope we can get some examples like:
Component: capacitors
Types: Teflon, PIO
Application: coupling between 6SN7 and 2A3.
Topology: DHT power amplifier stages
Observation: PIO is better

This would be a positive example (where we hear a difference) BUT also important would be NEGATIVE examples, to borrow from Romy's note on the Sansui thread:

Component: diodes
Types: FRED, Schottky
Application: DC power supply
Observation: no difference

That is what I mean.

Adrian


Posted by serenechaos on 12-08-2008
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 drdna wrote:
 Paul S wrote:
Well, I thought there was a lot of this going on all along, but that we just haven't come up with much that is "universal"
Yes, my thought is that there is NOTHING universal, but that these choices must be observed in CONTEXT of topology to be useful. An example:

 Paul S wrote:
As an offhand example, I wonder if the Cu PIO coupler would "work just as well" in the same circuit but with a 300B instead of a 2A3?
Yes, this is a good example. Maybe it DOESN'T, and we have that in our "library." Then suddenly we have something POWERFUL! We can think: what is the physical and electrical difference between the 2A3 and 300B and what is the physical and electrical difference between the PIO and the Teflon cap. From this we can begin to extract some useful ideas about the needs of topology for proper function.

I am going back to the car analogy: the Honda Civic and the Ford F-150. Initially we just classified them by the properties: wheels (yes/no), and engine (yes/no). So they seemed the same for a drive to the store. Then we added a new topology: a long distance trip, which only the Civic could do, so we discover a new property: gas mileage (high/low). And we formulate a hypothesis: for long distance trips, a high gas mileage car should be used.

In audio, we might say something like: (just an example) in DHT circuits, a capacitor with lower inductance should be used. Then we can begin to think why this would be the case.

 Paul S wrote:
And maybe this is why forums like this tend to fragment into "sections" that address more-specific (and putatively better-defined)
I think it is actually because it is done in a non-systematic way, without much thought given to figure out the scientific basis of observations.

 Paul S wrote:
As somewhat of a romantic, I also wonder if what we need is already "out there", spread out here and among the various OCD sites, like some wild, gigantic "Encyclopedia of Hi-Fi"? Shades of Jorge Borges!
I am sure it is, but it can only be used if it is compiled coherently in one place.

 Paul S wrote:
So, again, any thoughts on just how better to compile and use such a "raw" database?
Well, just as I said above. I would hope we can get some examples like:
Component: capacitors
Types: Teflon, PIO
Application: coupling between 6SN7 and 2A3.
Topology: DHT power amplifier stages
Observation: PIO is better

This would be a positive example (where we hear a difference) BUT also important would be NEGATIVE examples, to borrow from Romy's note on the Sansui thread:

Component: diodes
Types: FRED, Schottky
Application: DC power supply
Observation: no difference

That is what I mean.
Adrian


I don't think the above file system would be adequate.
Problem is, I don't know how the information could possibly be filed in a two-dimensional matrix type data base. 

I have built a few amps, have notes, and many pages of such information from a friend who's built many hundreds, over many years, and will tell you off the top of his head the difference in Sounds of different brands, and types of components, in different locations, but only in context with many other contributing factors, and how they are inter-related, and can balance each other, or hurt each other.  
And how component values change which specific components may be the "right one" for the desired sound... 
  I have tried to condense his years of discussions into generalitys, caps, resistors, so forth, it's still difficult to just write out, and "PIO is better" is not always true, (or false). 
r

Posted by drdna on 12-08-2008
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 serenechaos wrote:
I don't think the above file system would be adequate. I have built a few amps, have notes, and many pages of such information from a friend who's built many hundreds, over many years, and will tell you off the top of his head the difference in Sounds of different brands & types of components, in different locations, but only in context with many other contributing factors.
Yes, I think I have tried to not only make obvious but to emphasize that we are talking about observed inter-component interactions within a specific topology. There is no one "ideal resistor" dictum, etc.

It is exactly because there is so much seemingly non-generalizable information out there that an attempt to categorize, codify, and analyze it should be made. I'm simply asking for some raw data, rather than naysaying against the process itself.

The fundamental question is whether it is all reducible to resistance, inductance, and capacitance (so to speak), or whether we can discover evidence of properties of audio circuits that are important but not currently recognized as such.

Adrian

Posted by Romy the Cat on 12-09-2008
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Serenechaos,

You did not mention one another ugly fact the all recommendations about the “quality” of components have any validity in a relatively short distance. It might be no true if we are taking about vintage element but the contemporary production is very vibrant. I do not want to generally but it is highly possible that a contemporary company that produces a very good product with a few years surreptitiously turns this very product into a very bad product. I have vitals it myself. For instance the gold plated metal film Holco resistors a few year back were very good and then the quality went down and down and down. I know a few products hat used Holco at critical location and those products from 1997 and 2007 are so different in sound that you would never believe that they are the same products.

Adrian,

I think you are trying to get is not fruitful. You see the sonic contribution of some kind of specific element in the specific location is possible to assess only in context of the whole “philosophy of sound” that a person expects, to get from a given audio devise. I am not taking about synergy of balancing the thighs out but rather about having an evaluating scale upon which all judgments are reflected.  Collecting opinions is educational but not truly useful. There somewhere at my site a link to many pages of detail observation about different caps.   I never was able to read it through and did not found it useful for myself. But my own perception of those thighs is kind of bizarre and I always try to address my very specific need in DIY audio. I so much do not like it that I would like to believe that I never will be doing DIY audio again.  So, if I found something that “works” then I truly would like to forget and do not temp myself to use it in future. Strange but it is what it is….

The Cat

Posted by serenechaos on 12-09-2008
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Thanx Romy,

Yes, fitting "time produced" into the matrix is an important piece of the puzzle, don't think I mentioned that one. 

Holco resistors are a great example, are in my notes, along with other resistors, and caps, that have changed. 
But how to keep up with it? 
Without building amps everyday?
Staying in touch with someone who has, for their entire life is the only way I know... 

And  recommendations changing, due to something being "the best I know of" one week, then "hey this other thing works better with that thing" the next week... 

Or how do you list something like "silver?" 
Wire, or in caps, whatever, effects Sound, not just electrical flow, magnetics, corrosion... 
Despite the advertising hype, Sound effect is not always good, silver can ruin sound, make things too bright, thin, brittle, sharp...
But, I sure wouldn't put it in a "bad" column... 
Oil caps can make Sound sluggish, thick, blah, blah, if blah, blah... 
Mundorf Silver & Oil caps -- are they going to be the best or worst of both, or even worth trying?  In what position? 
(I love them, they make great, slightly warm, coupling caps for SETs, almost as detailed as the best teflons, but smoother, not harsh, glaring. 
Oil damps & smooths & silver is fast. Rich harmonics, very nice). 

Maybe useful to make some kind of look-up chart, but I can't think of how to organize it in a useful way yet, or I'd better organize my notes. 
I'm not done building, still have a way to go addressing my specific needs in DIY audio. 
Need to finish the horns, "teach them to sing,"  build individual amps for each... 
It seems like a long road from here... 

Robert


Posted by drdna on 12-09-2008
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Well, it seems no matter how hard I try, I am never able to get anyone to think outside the box here. Sort of frustrating.
 Romy the Cat wrote:
For instance the gold plated metal film Holco resistors a few year back were very good and then the quality went down and down and down. I know a few products hat used Holco at critical location and those products from 1007 and 2007 are so different in sound that you would never believe that they are the same products.
Well, this would be a great opportunity, actually. I don't care about finding a great brand resistor, you see. But the learning is great. We can ask: what applications were these used in? How did the "quality" decline: what physical and electrical characteristics were different. The in the context of the topology, we have learned something.

I have heard no one offering help, only saying "it's impossible." Oh well. It is correct that a person lots of amplifiers every day for many years would have some experience. BUT, I also hoped a lot of people building a few amplifiers each could all get together and accumulate a similar amount of data.

However, if no one is willing to think about it this way or participate, the idea of a collaboration to build a database is a dead issue, I guess. I cannot do it alone.

Sad
Adrian

Posted by serenechaos on 12-09-2008
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I didn't say "it's impossible." 
I'm saying "I don't know a format that would be functional @ this time."   

Gotta work now; will try to condense into something more resembling one page of notes for resistors or something & post. 
Robert

Posted by Paul S on 12-09-2008
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Adrian, as a purely practical observation, I just re-read your examples of the format you suggest, and I have to say I would need a good deal more information than that before I could figure out enough of what was going on with the components in question to be able to make useful decisions for my own applications.  By this I mean to say that even a brief anecdotal context would be of more value to me than the few related-but-still-isolated facts profferred with the examples.

So, what other sorts of examples do we have?

I'll assume that everyone following here has spent some time at Joe's Tube Lore, and maybe they've read the Cap Tests, too.  While a LOT of relevant information is missing from these "comparisons", still, there are enough terms getting re-cycled that one can almost get some idea what those guys are talking about, setting aside for the moment the critical issue of consistency, example-to-example, within any given make, model, value, year, etc., etc..

What I have found interesting with the above-cited "comparisons" is that even though I might actually agree with the "tester's" observations, as such, there are always things peculiar to my own particular usage that I wind up weighting more or less heavily than the tester did.  Or, I find out that the tester either did not notice or he glossed over traits that I find important with respect to my own final decisions.  So, I followed up on what I read, paid my money, did the damned DIY, and now I hear pretty much what he heard, only I hear other stuff, too, and/or I come to different conclusions about the relative weighting of the tester's observations.  Does this mean I basically wasted my time and money despite the "information"?  Yup.  So, how could we keep the info "vital" (which is to say, dynamic)?

In practical terms, this seems to encourage at the least a "Wikipedia"-type format, as unwieldily as that might become (and as much as it might discourage the hard-working "tester", who eagerly posts his hard-won findings only to have them subsequently picked apart by crows).

Some sort of cross-referencing system would be important, too.

If I think of this idea as a "Living Encyclopedia of Hi-Fi", it sounds quite interesting and even potentially useful.  Sort of like the Good Sound Club site, with a different name...

Best regards,
Paul S

Posted by drdna on 12-09-2008
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 Paul S wrote:
Adrian, as a purely practical observation, I just re-read your examples of the format you suggest, and I have to say I would need a good deal more information than that before I could figure out enough of what was going on with the components in question to be able to make useful decisions for my own applications.
That may well be true. I am suggesting it on Romy's site because we all have fairly similar systems and ideas about audio. This may reduce such frustrations.

Again, the goal is to simply have observations, not a catalog of successes (e.g., the wonderful Capacitor X). Exactly the observations you refer to:

 Paul S wrote:
I find out that the tester either did not notice or he glossed over traits that I find important with respect to my own final decisions. So, I followed up on what I read, paid my money, did the damned DIY, and now I hear pretty much what he heard, only I hear other stuff, too, and/or I come to different conclusions about the relative weighting of the tester's observations.


This can be very fruitful, if you then elaborate on the application and how the device met or fell short of the goals. If we gain insight into the important attributes of various functional positions in a circuit toplogy, we can begin to predict what devices to use or consider novel toplogical solutions.

Adrian

Posted by Romy the Cat on 12-10-2008
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… then it is definitely not a Cat.

Well, I disagree with a need for it but if not only Adrian feels an interest in this then let me know and will come up with a friendly interface and a principle for data organization to make is useful. The whole notion of Components Indexation has a heavy DIY odor as far as I concern and I wonder when/if I implement then in what section of my site I would need to put it...

The Cat

Posted by serenechaos on 12-10-2008
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If possible, please explain the difference. 
In DIY odor
And odor of whatever it is you're doing with this site? 

I sometimes think part of it is ego (of course how could one not have a sense of pride in accomplishment, that is a good thing), doesn't matter one way or another. --   

I associate Romy and "GoodSoundClub" with "Advanced Audio and Evolved Music Reproduction Techniques." 

From my experience, "Advanced Audio and Evolved Music Reproduction Techniques," and/or good Sound, seem to require quite a LOT of DIY, (whether I like it or not, does not matter).  
It just isn't available at any price commercially above a certian level.  

What I see being done with this site is one mans methodical, pursuit of "Advanced Audio and Evolved Music Reproduction Techniques," which can be very educational, saving readers much time and frustration in their own experiments.  
Of course it's not a "cookbook" with exact "recipie" to get Sound I want in my room, but it is what it is. 
It documents success and failures, in context, seemingly unabridged (or, should I say less sensored by moderators BS).  
Very useful, not available elsewhere. 

Maybe I define DIY wrongly? 

Robert


Posted by Romy the Cat on 12-10-2008
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*** From my experience, "Advanced Audio and Evolved Music Reproduction Techniques," and/or good Sound, seem to require quite a LOT of DIY That is exactly what I do not like or I would say do not agree.

We all agree that DIY doe not automatically assumes any Evolved Music Reproduction Techniques but the Evolved Music Reproduction Techniques does not automatically implies heavy DIY. Do you see a lot of other “regions of enrolment” where “Evolved Anything” would demand DIY? I do not think so. Yes, the DIY in other fields might yield more evolved results but it is voluntary and optional opportunity not demented one. Anyhow, if you guy feel that this components indexation might be useful then I will put something up. T

he caT

Posted by Romy the Cat on 12-15-2008
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 drdna wrote:

Again, the goal is to simply have observations....

I just put a few lines of code together with the interface for the “Index of Components”. Let see where it goes. I did not test it well but it shell be stable. Feel free to upload valuable data as well as any test garbage you wish. I will clean it before end of testing. In future I will add the anti-robot security and reporting service. At this point I keep the posting right open to public. Contact me if you have any problems, complains, or comments. The hierarchy of the elements is very flexible and I can put in there whatever I wish...

http://www.goodsoundclub.com/Components.aspx

The Cat

Posted by drdna on 12-16-2008
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I am happy to have this here. I hope our members will take advantage of this and fill it up with information. I certainly will note any surprising observations I have with EAR 834 if I modify it.

It seems more like a general catalog of elements, which I expect is how most people view this project. Again, I want to emphasize, I feel the importance is a tool to understand the physical and mechanical aspects of electron flow in specific topological circumstances.

I am especially hopeful people will post any unexpected results. Any unique topological circumstances where an element fails to give the expected result.

Also, maybe a link on the front page for easy access?

Adrian

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