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Old 11th November 2012, 08:04 PM   #711
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Quote:
Originally Posted by bcmbob View Post
OT Comment.

P.S. I still want a photo of Andrew helmet on - behind the wheel .
Bob,

Still way off topic.

Here is a official photo of Andrew in his helmet.

Click the image to open in full size.

OK, just fooling. Andrew, No offense intended. I'm sure you are better than this bloke.
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Old 11th November 2012, 08:57 PM   #712
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Dario, you have used this "equally bad" reasoning about fastons all along, and I think it is flawed. Imagine a piece of consumer-oriented crap and any decent audio-grade component. Now introduce some deleterious element into the signal path, and tell me which piece of equipment will be more seriously affected. The junk gear will probably not change much at all, but sound just a little junkier. That delicate, precision piece of gear will perhaps lose soundstage qualities, frequency accuracy, and many other aspects of signal quality we relentlessly pursue.

I expect that the elimination of crappy connectors will have far greater impact than all the bothersome orientation of parts.

I can select any component anywhere in my system, especially wire, and it will initially sound somehow different if reversed. All else being equal, reverse any single part and it'll probably sound different. Better? Well, you can convince yourself of that if you want to. In a few minutes or hours or days, it will probably sound exactly the same as it did before reversal, but you'll never realize it.

A better test than Andrew's is to find the "optimal" orientation of any two sensitive parts according to listening tests, not label or other physical characteristics. Permanently mark the parts accordingly. Insert one part in a circuit in the optimal position. Insert the other part in an equivalent circuit in the reversed, sub-optimal position. Play them for a week (I do believe in burn-in.). Listen again. Any difference? Okay, reverse their direction, but keep everything else the same. After a week, is there still a difference? Does the optimal sound now come from the opposite circuit? If you can answer "Absolutely yes, without a doubt," I will start to play with orientation.

I don't mean to be harsh, but I see some evaluation methods here of questionable value. I am open to being convinced, but only after careful testing. I will accept subjective evidence, but only if it's obtained in a controlled manner. Just swapping parts around, especially using poor quality connectors, is not an appropriate test for the level of performance we seek.

Peace,
Tom E
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Old 11th November 2012, 09:39 PM   #713
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Quote:
Originally Posted by madisonears View Post
I expect that the elimination of crappy connectors will have far greater impact than all the bothersome orientation of parts.

A better test than Andrew's is to find the "optimal" orientation of any two sensitive parts according to listening tests, not label or other physical characteristics. Permanently mark the parts accordingly. Insert one part in a circuit in the optimal position. Insert the other part in an equivalent circuit in the reversed, sub-optimal position. Play them for a week (I do believe in burn-in.). Listen again. Any difference? Okay, reverse their direction, but keep everything else the same. After a week, is there still a difference? Does the optimal sound now come from the opposite circuit? If you can answer "Absolutely yes, without a doubt," I will start to play with orientation.

Peace,
Tom E
Tom,

CONNECTORS

First, on the subject of connectors, solder, and crimped connections. Are there any scientific studies of these approaches? I get that steel is magnetic and likely to interact with the electromagnetic signal. I could even buy that connector materials have some difference, but I struggle to understand that as a big difference. As solder .vs. crimp, I'm having trouble believing a significant difference, or explaining why. Please point me to somewhere to read more on the subject. I want to better understand.

If I understand your approach, it would seem that you would avoid any slip connector and solder all connections directly to the board? I could see a plus in eliminating connectors entirely. If you are using a connector, then a Molex as used on the FE RC board input, a pair of fastons of a non-steel variety, or a screw type as Bob suggested earlier would all seem to rely on a mechanical pressure being used to make an electrical connection. In this vein, a faston would seem to have an advantage of greater contact length and force. What am I not getting?

SUBJECTIVE EVALUATION

As for your proposed test approach, the issue is the time between subjective evaluations. In 35 years of subjective evaluations professionally, I have often seen risks in subjective evaluation separated by too much time. I see that you are trying to address that, and it may work given two equal comparison systems.

I guess this comes back to burn in. I think of burn in of an electrical component as similar to getting tires up to a stable temperature on a car before testing it. In the case of capacitors, I don't know how to judge how long it takes for internal components to stabilize, but in AC operation, they should reach a stable condition where back to back comparison of orientation should be possible. If we were in DC bias operation, then a reforming operation might be appropriate, but with film caps operating in AC such as the DC blocking cap at the input of an amplifier, it seems like a burn in for an orientation switch shouldn't be necessary.

A test variation that I might suggest would be to burn in your caps as long as you feel necessary. Do a back to back to back evaluation of orientation. Make notes. Then swap your orientation from the original, burn in as needed, then do a back to back to back evaluation of orientation. Make more notes and compare to the original notes. I think this is closer to Andrew's approach although he would add a month to make sure that the evaluator was consistent. That's fair.

Please take these comments in the spirit offered, that of learning and constructive debate. My intent was not to criticize, but discuss.

Jac
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Old 11th November 2012, 09:40 PM   #714
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Instructive, additional thoughts, instead of just more criticism.

Testing input caps. I firmly believe fastons are detrimental. They might work okay for power leads, but not for signal. Instead, use a pigtail wire soldered to the board, just long enough that soldering on the other end will not heat that junction enough to loosen it (couple inches?). Crimp securely and solder the leads of your cap to the pigtail and your input jack or wire leading to it. And perhaps quit using those awful nickel plated terminal screws. No more lossy mechanical connection of questionable quality/reliability. More work? Well, yeah, some. More accurate results and better sound? Probably.

Jac, the addtional inductance of wire or long leads on the input cap should not matter here because of the high input impedance. Typically, the inductance of IC's to the input does not matter very much, so why should an additional piece of wire? Inductance is more of a factor in speaker cables or in other circuits with low impedance loads. The inner/outer foil business is pretty much over rated, too. I believe it is a concern only for noise in high gain circuits such as phono preamps, and even there it might not be conclusively proven to be a significant factor. The signal flows through the inner and outer foil no matter which way the cap is used, and it is probably inaudible unless you have a really crappy cap.

Andrew (or anyone else), please correct me if any of that is wrong.

Peace,
Tom E
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Old 11th November 2012, 09:42 PM   #715
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Quote:
Originally Posted by AndrewT View Post
Most faston sockets will be steel.
The faston blade can be steel, or more likely brass and just occasionally copper.
Not in my experience, Andrew....

I've buyed them also from DIY stores and they were mostly made of brass.

As the ones indicated in BOM.

Quote:
Originally Posted by madisonears View Post
Dario, you have used this "equally bad" reasoning about fastons all along, and I think it is flawed. Imagine a piece of consumer-oriented crap and any decent audio-grade component.
Sorry Tom but you're completely wrong here... IMHO.

'Consumer oriented crap' has often magnetic/ferrous connectors, it's the 'high-end' gear that has brass connectors...

Only a little part of high-end gear has copper connectors.

Quote:
Originally Posted by madisonears View Post
I expect that the elimination of crappy connectors will have far greater impact than all the bothersome orientation of parts.
Yes and no.

Yes, brass connectors removal has a beneficial effect.

No, part orientation can have a bigger impact on sound.

Quote:
Originally Posted by madisonears View Post
If you can answer "Absolutely yes, without a doubt," I will start to play with orientation.
I didn't it for every single cap but for C7 I can say 'yes, without a doubt'

Quote:
Originally Posted by madisonears View Post
I don't mean to be harsh, but I see some evaluation methods here of questionable value.
I'm not the first one to use sockets and connectors (Peter Daniel docet) and I've had consistent results using them since the My_Ref, rev C...

Quote:
Originally Posted by madisonears View Post
Just swapping parts around, especially using poor quality connectors, is not an appropriate test for the level of performance we seek.
You perfectly know that I'm right since you confirmed most of my results...
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Last edited by ClaveFremen; 11th November 2012 at 09:47 PM.
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Old 11th November 2012, 10:57 PM   #716
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I didn't make a comparison between soldering and crimping. Not sure where you saw that.

The difference is in the connection. Optimal connection is air tight, metal to metal. Crimping is the best way to guarantee that. It doesn't need to be complicated--a squeeze with pliers is often enough. Solder should only strengthen and protect the connection. Mechanical slip connectors are a bad option, and the materials used in most fastons are the worst.

If you don't believe there is a difference in the sound of steel or nickel and copper connectors, then there isn't much point in having a disussion here. Sorry if that's insulting, but there is simply too much evidence to the contrary. It's not in my interest to lay it out here for you.

I avoid mechanical slip connectors wherever possible: certainly in low and line level signals, but even in speakers and crossovers. No need to go nuts with that philosophy, but if you can crimp and solder a connection instead of a slip connection, why not do it? Threaded connectors that can apply constant, reliable, significant pressure are also adequate, but the plating and base materials involved frequently make those less than ideal.

Regarding orientation testing, there is no time lapse with my method, and that's the beauty of it. Components are used simultaneously in opposite orientations (one optimal, the other not) in otherwise identical circuits. Comparison is instantaneous. Then the circuits are run for a while. My contention is that, with the transmission of signal over a period of time, the components will equalize and no observable difference will exist. If there is no difference between the two circuits after a passage of time, the test is over. If there is still a difference, then reverse both components in each circuit. Repeat comparisons immediately and after a passage of time. If there is still a difference and one circuit sounds better than the other (should now be the opposite of the first trial), I will begin to believe that orientation is a significant factor.

All other tests rely on audio memory, which I believe is better than some experts make it out to be. However, my test eliminates it.

Peace,
Tom E
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Old 11th November 2012, 11:36 PM   #717
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Dario,

Yes, we agree on so many things. I trust your judgment, but I'm not sure you've thought this through all the way. I find it odd that someone who is so careful about design and execution would install fastons in critical parts of a circuit. The sil sockets for small components are much different from those clunky fastons. I'm of the opinion the differences may be negligible for the sockets, but not for the fastons. Unplated brass parts will get you closer to acceptable, but they're certainly still not ideal.

I think you missed my point about junk vs decent gear. Perhaps it was my fault, so I'll try again. The junk gear already sounds like junk. Put a bad connector or other harmful element in the signal path, and it won't have much effect. It still sounds like junk, probably no worse than before.

Take a nice piece of equipment, or even a component inside that equipment, and add something "harmful" to the signal path such as a bad connector. Chances are good that the beautiful qualities of that nice piece of equipment will be more seriously affected. Can't make an exact prediction, but it will harm the FR, soundstage, imaging, etc.

Perhaps the same thing with caps. When you're testing a medium or low quality cap with poor resolution, those connectors might not upset the sound. Now put in a copper foil cap with high grade film or a Russian Teflon. The cap has very subtle characteristics that are desireable: smooth, detailed highs, 3D soundtage, etc. That connector might affect those characteristics more than it affected the lower qualtity cap. You might hear that both caps sound similar because the connector has masked the superb qualities of the better cap.

I'm not saying the results people got from testing are wrong. I'm saying the effect of bad connectors might make their comparisons inaccurate, whichever way that goes, because some subtle differences between caps will be swamped by bad connectors, even if all the connectors are the same.

Perhaps Bob will have something to contribute after he removes all his sockets. I wish he would start with just C13 and let us know the effect.

When you wrote about C7, was your test according to my description? Did you use parts in opposite orientation in two amps and then let the amps run for a while and compare again?

What type and value did you finally decide on there? Seems like several builders had difficulty choosing a value. That is only a PS bypass cap for the 318 chip. I know every part contributes, but is that one really so important that the orientation makes a difference? Is it different in the FE than the Rev C?

Peace,
Tom E
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Old 12th November 2012, 12:57 AM   #718
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Quote:
Originally Posted by madisonears View Post
I'm of the opinion the differences may be negligible for the sockets, but not for the fastons. Unplated brass parts will get you closer to acceptable, but they're certainly still not ideal.
Tom,

I know very well how the amp sounded with Zns I was previously recommending, when I've mounted my small fastons I've noted no big differences.

But as I've already stated:

Quote:
Originally Posted by ClaveFremen View Post
Brass signature (slightly thinner and less natural than pure copper), though, should be taken into account when evaluating caps branched via fastons.
That means:

Those fastons are useful to evaluate differences among caps but the 'absolute' timbre and performance is partly impaired by connectors signature.

In my experience, though, when good quality brass is used the difference is audible but not so big to impair comparison.

Quote:
Originally Posted by madisonears View Post
Chances are good that the beautiful qualities of that nice piece of equipment will be more seriously affected. Can't make an exact prediction, but it will harm the FR, soundstage, imaging, etc.
While I strongly agree that connectors and cabling quality is important to achieve ultimate performance it must be taken in account that we're talking of an order of magnitude less Vs. passives selection, IMHO.

Quote:
Originally Posted by madisonears View Post
You might hear that both caps sound similar because the connector has masked the superb qualities of the better cap.
In my experience the only material with such masking abilities is steel... brass is a good quality material for connectors.

Quote:
Originally Posted by madisonears View Post
I'm not saying the results people got from testing are wrong. I'm saying the effect of bad connectors might make their comparisons inaccurate, whichever way that goes, because some subtle differences between caps will be swamped by bad connectors, even if all the connectors are the same.
In my experience it's not so... though I agree that some 'absolute' statements I've read here can be misleading, the brass signature must be taken in account.

Quote:
Originally Posted by madisonears View Post
When you wrote about C7, was your test according to my description? Did you use parts in opposite orientation in two amps and then let the amps run for a while and compare again?
Yes... C7 selection has been a pain...I've had to evaluate several caps (in both orientation) and the most difficult task was to identify what was the most correct sound... but every time I've changed direction the difference was consistent, even if tens of hours of use passed.

Quote:
Originally Posted by madisonears View Post
What type and value did you finally decide on there? Seems like several builders had difficulty choosing a value.
The value is 10nF (15nF also good), type FKP2 100V (voltage rating is crucial here).

Much better but out of production ERO KP1834 (polystirene, also film foil)

Quote:
Originally Posted by madisonears View Post
That is only a PS bypass cap for the 318 chip.
I know every part contributes, but is that one really so important that the orientation makes a difference?
Yes, C7 it's one of the most important caps, Presapian was right about it (though I can't support his conclusions...).

Quote:
Originally Posted by madisonears View Post
Is it different in the FE than the Rev C?
No, same recommendations apply.

If you have FKP2 63V buy a 100V one, mount sockets and compare... (also directions )
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Old 12th November 2012, 11:16 AM   #719
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Quote:
Originally Posted by madisonears View Post

Perhaps the same thing with caps. When you're testing a medium or low quality cap with poor resolution, those connectors might not upset the sound. Now put in a copper foil cap with high grade film or a Russian Teflon. The cap has very subtle characteristics that are desireable: smooth, detailed highs, 3D soundtage, etc. That connector might affect those characteristics more than it affected the lower qualtity cap. You might hear that both caps sound similar because the connector has masked the superb qualities of the better cap.

I'm not saying the results people got from testing are wrong. I'm saying the effect of bad connectors might make their comparisons inaccurate, whichever way that goes, because some subtle differences between caps will be swamped by bad connectors, even if all the connectors are the same.

Perhaps Bob will have something to contribute after he removes all his sockets. I wish he would start with just C13 and let us know the effect.

Peace,
Tom E
First, let me concede that, with the exception of the FE amps :-), my system may be a lot closer to junk than yours, so my experience may be proving your point rather than contradicting it. Also, that I am a relative noob here and my earliest evaluations were probably not as careful as you or I would like. Although I don't have more than one amp for comparison by your approach, I will do more careful experimentation on orientation in future.

All that said, the limited experience of my test suggest an opposite conclusion to me. If you recall, I was underwhelmed with the sound of the True Copper caps when I first reviewed them. Dario suggested that I needed to compare orientation. Changing orientation showed a clear difference to my ears and it was subtle differences as you suggest, soundstage, clarity, harmonic air. I have seen small differences between C13 caps that were overall consistent with evaluations by Dario and others. All of this using fastons for C13. Even more horrible, I used clip leads to parallel 3 Russian FT3 caps in order to get close to 1 uF for C13. Yet those caps sounded like the review of other reviewers. Talk about recording room harmonics and incredible detail, the FT3 provided in full. It is possible that I am missing even more differences due to the low quality of my system, but it does seem that useful small differences can be understood using fastons. I look forward to the day soon that I can make a faston to solder comparison.

In the meantime, I agree. We should all put lots of pressure on Bob to do a careful and full evaluation of fastons C13 .vs. soldered C13 :-)

Jac
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Old 12th November 2012, 06:01 PM   #720
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Originally Posted by lehmanhill View Post
Although I don't have more than one amp for comparison by your approach, I will do more careful experimentation on orientation in future.
Jac,

You have two monoblocks? That's two amps. Use one with optimal part orientation, the other opposite. You can't test in stereo so you can't really hear spatial cues, but you can test FR and get a good sense of tonal qualities and "air" with mono signal. After a week or so, is there still a difference? If not, test is over. If there is, swap directions of parts in both amps. Listen again. Did the better sound move from one amp to the other? Play the amps for a while, then listen again. If one amp still sounds better after a week or so, then orientation is a factor. This method is simple and foolproof. If you hear a difference after the parts pass signal for a significant length of time (hours don't count--days at least), then orientation might be a factor. If you repeat the test with part's direction reversed in each amp and better sound moves from one amp to the other, then orientation is the most likely factor.

From what all you experimenters are saying, it might be the most important factor, even more important than which brand or type of part you're testing. I find that concept very difficult to accept, but I'm willing to learn. I cannot understand why any manufacturer would create a part that was almost disfunctional passing an AC signal in one direction and completely superior in the other direction, and then not indicate to the end user which direction was better. It's ridiculous to suppose that they don't know or don't care, or that they expect the end user to find that out for themselves or leave it to chance. That is not a reasonable business strategy when your sales depend on performance.

I don't mean you won't hear ANY difference between caps or other parts with less than excellent gear, but subtle differences may be swamped. Maybe not. I bet your system is good enough to select the best cap for your system! If all the testing is done on your system, then that's your frame of reference. Not much else really matters, including my or anyone else's opinion. I'm not saying your conclusions are incorrect, but make sure you're testing carefully. A lot of people like those Russian caps. I've never tried them because I get a little spooked buying parts on eBay from Russia. I guess I'll just have to get over that and grow...er, I mean get a pair.

Anyone can get rid of fastons and continue testing via pigtails. Maybe it won't matter at all, and I'll have to buy you all lunch so you can watch me eat crow.

Peace,
Tom E
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