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Old 28th October 2011, 03:52 AM   #17031
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(17004 contd.) What was good enough and perhaps problematic with the 'old days'?
Well, when it came with interconnect cables, sometimes a really cheap dielectric that might be used in a coaxial cable, would multiply the effective capacitance/meter to levels that would slew rate limit the tube or transistor amplifier driving it, with over 2M of lead. It must be said, today, that most cables are better than the worst examples for 40 years ago.
Tin on tin connections are often used, even today, for reasonably reliable connections. This was the dominant connector contact that I found 40 years ago. It is interesting that GOLD/TIN connections are worse! Today, it is difficult to say what kind of contact you are getting: Gold, nickel, chrome? I really can't be sure, with the cheap stuff. However, I do know that GOLD/GOLD is pretty good as a connector contact, known for ages by the Germans, Russians, and the American military. I might call that 'progress' if I am allowed to.
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Old 28th October 2011, 04:18 AM   #17032
Pano is offline Pano  United States
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I certainly agree that cables, connectors and terminals have gotten much better over the past 40-50 years. I'm not as old as most of you fellows here, but have owned and worked with a lot of old stuff that had really crappy connectors. Who remembers those cheesy little screw terminals on the back of amps? Cables weren't great either.

Mostly I'm taking mechanical qualities, but maybe better dielectrics, too.
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Old 28th October 2011, 04:53 AM   #17033
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at the risk of being tarred and feathered... having at my disposal the assistance of a world class wire manufacturing facility, some many years ago I had wire made with all things identical OTHER THAN the metal itself. I had three versions made: copper (high purity), Ag plated, and Ag (high purity). They were made into essentially identical interconnects. Enough to do a full signal path.

It was not difficult to discern the differences in the sonics between them. Not at all.
No, it was not double blind or ABX, but the listener had no way to know which set of cables he/she was hearing.

The way that it manifested itself was in the overall balance tonally, bass to highs. And also, importantly, in the timbre of things like cymbals, where the differences were quite noticeable.

Could an EQ have made the same differences? Not really, since the differences in things like cymbals seem to also relate to the sound of the decay (splash) as much as the attack. Also "stresses" with things like sibilance appeared to be greatly or completely "resolved" and less of an issue with one of those three test types.

At the time, this is NOT what I was hoping for. Just for the record. I felt then as now that what was coming out and being heard was confounding, running contrary to any known engineering principle.

To put it in the proper perspective I like to use this analogy with sight.

If I put out a flat black square and ask you to look at it, you see nothing but black. If I take a tablespoon of salt and randomly splash it on the square, you will see a random salt pattern. If I put a lot more salt on the square you will see mostly the salt as a whole and the black creeping through. But if I put only a small amount of salt on the flat black square you will notice the salt as an imperfection of the clean black surface. Move that salt around, you will see it. It is this last situation that one finds with audio in a very clean system, "blameless" if you wish to use that term - or better - that one can begin to notice the small amount of salt sprinkled on the black surface. (Feel free to reverse the colors and swap black for white... fyi.)

I think this is why some, indeed many, even researchers, have not heard or found this sort of thing. They are moving only a few grains of salt amongst a great many.

Let me add, that given how the ear/brain seems to analyze what comes into it, familiarity with a given system (yours) makes it possible for you to hear things change that almost everyone else can not, is not able to, hear. In effect your brain has learned what the pattern of salt "looks like" and subtracts that from any changes to detect them. HOWEVER, this takes a lot of processing power, and THAT subtracts from the ability to detect subtle changes none-the-less. But in your home system you will likely have greater resolving ability than anyone else - all things being equal - for this reason.

(this means that in many instances one simply can not detect the sonic differences, and in a smaller group of cases one CAN detect a change but that change is unclear or uncertain...)

So the best situation is where the system makes a very very excellent and low distortion presentation (whatever the heck that means in empirical reality) because this presents the brain with information that requires the LEAST processing to decode/understand. That leaves more processing for subtleties, since music is realtime, and so the depth of information depends on not having to spend too much brain figuring it out, less time on the basics.

This explains why I have had little faith in the published tests on this matter thus far - there is nothing that shows that the presentation meets some criteria for detecting subtle cues in the first place. That is necessary, not a luxury.

Anyhow, that's my viewpoint.

_-_-bear

PS. I do not think that R,L&C adequately explain or predict what can be heard.

PPS. I am allergic to tar and feathers.
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Last edited by bear; 28th October 2011 at 05:00 AM. Reason: punktuashun
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Old 28th October 2011, 04:57 AM   #17034
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I have the feathers ready, the tar is heating up.
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Old 28th October 2011, 05:32 AM   #17035
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Old 28th October 2011, 07:22 AM   #17036
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A good place to start the discussion may be to agree on the different possible categories of cable-induced sonic differences:

1) Source>cable interaction.
2) Cable> load interaction.
3) Cable contributed signal (RFI, piezo, dielectric storage, etc...)

These three may indeed interact with each other, but I cannot think of another discrete source of signal transfer modification. I can say with some experience, having wired miles and miles of balanced cabling in radio and recording studios that high-current discrete low driving impedance output stages and terminated inputs show very little sensitivity to cable effects including RFI. Conversely low-current/relatively high output impedance line-level output stages coupled with high input impedance input stages show high sensitivity to cable changes and RFI pickup.

Also, in many systems that people think have a "pristine" quiet noise floor, the insertion of a high quality line transformer like a Jensen can give a huge improvement in the noise floor quality, that can surprise even experienced listeners. Eliminating galvanic connections between system components can eliminate loop currents uncorrelated to the signal. Whether the sonic compromise that the transformer incurs is a lesser or greater evil than the improvement in the noise floor varies from case to case.

My $0.02 worth as usual, YMMV.

p.s. re: screw terminals: there is no connection other than soldering more reliable than a high-pressure screw connection, which can have such a gas-tight contact between the wire and terminal that oxidation has trouble getting established, and the extreme-pressure wiping that occurs during tightening helps break through the existing oxide films. In all my years of audio engineering I have yet to see one generate distortion, become intermittent or fail, unlike every other connector system other than the hypertac style. I GREATLY prefer putting together a fixed-location system using screw terminal connections. I love older Orban, DBX and many other true pro audio pieces that came so equipped...if only for this reason.

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Last edited by hhoyt; 28th October 2011 at 07:33 AM.
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Old 28th October 2011, 07:45 AM   #17037
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Ok, if the request is for experiences and not conclusions, then here goes:

PART I

I started out my hi-fi hobby on a tight budget, especially during college. Thus, I ended up with a number of systems wired with 16 ga zip cord from Radio Shack. It sure seemed better than smaller speaker cable, but I never really compared.

Then I discovered the world of subwoofers, and ventured out to buy one. While buying the necessary cable for the high-powered bridged amplifier, I decided that it was about time to upgrade my full-range speaker wires to something nicer than Radio Shack wire. Still being budget conscious, I selected the absolute cheapest speaker wire available at the audiophile shop by the foot. Upon arriving home with my new subwoofer and piles of wire, I decided to take small steps. Rather than change everything at once, I decided to first upgrade my full-range speaker wire, and then begin the longer process of introducing the subwoofer (hopefully while listening to some music). Here's where my mind was blown. After installing the cheapest "audiophile" speaker wire on my full-ranges, I suddenly attained so much more bass from my existing speakers that I began to wonder whether I even needed to add the subwoofer! This new wire was nothing any more fancy than 14 ga JSC Wire & Cable "Giant Speaker Wire" - since then, I put more faith in gauge than in the price tag. I did add the subwoofer after I picked my jaw up off the floor, and it did make a huge difference after all, but I'm really glad that I spent those few minutes listening to the intermediate system sans subwoofer but with 14 ga JSC wire.

PART II

The premium audiophile retailer in the area hosted a demonstration from Transparent Audio, who showed their magical cables incorporating LCR networks that somehow work perfectly with any amplifier output stage, any speaker crossover circuit, and basically in any system it should provide an improvement. The salesman assured everyone that they would hear a clear difference in cables, no matter where they were sitting. I'm one of those people with 10,000 hours of listening; I can hear jitter, I can hear distortion, and I can tell the difference between 24-bit and MP3 in a blind test. But I must admit that I did not hear a single difference during the A/B cable comparisons staged by Transparent Audio. Given my electrical engineering background, I can't see how a fixed network can correct for a random amp+speaker combination, and given my budget I can't justify $10,000 per speaker cable. But I really do enjoy nice, expensive things, and I was certainly open-minded to hear better-sounding music than I had ever heard before (or at least better than the crappy wire that was promised as a night and day contrast) even if I wouldn't be a customer. To reiterate, I heard nothing to show that Transparent Audio had accomplished anything but selling high-budget studios on their brand. Thus, I had no reason to alter my faith that physics has more to do with the sound than the price tag.

I do own a pair of $100 Transparent Audio RCA cables, but they actually pick up radio stations when no other cable has done so in the same installation.

My apologies for throwing in a few "conclusions" there amongst the experiences.

Last edited by rsdio; 28th October 2011 at 07:47 AM.
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Old 28th October 2011, 10:38 AM   #17038
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Quote:
Originally Posted by hhoyt View Post
A good place to start the discussion may be to agree on the different possible categories of cable-induced sonic differences:

1) Source>cable interaction.
2) Cable> load interaction.
3) Cable contributed signal (RFI, piezo, dielectric storage, etc...)
That's a good start ...

the cable discussion came up in common with the increasing of bandwith in audio amplifiers. Nowadays you can speak of high frequency amplifiers and this results in interactions.

Next, many cable designs are coming from "designers" which have now, or small, interdisciplinary skill in HF engineering and / or cable design. So the doors are open for "uncontrolled" interactions. Speaking in the studio / pro-audio gear of the "golden days" in Germany we had the 600 ohm standard for input- / output impedances and a standard level (1.55V dBU) for signal voltages.
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Old 28th October 2011, 12:44 PM   #17039
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Quote:
Originally Posted by bear View Post
at the risk of being tarred and feathered... having at my disposal the assistance of a world class wire manufacturing facility, some many years ago I had wire made with all things identical OTHER THAN the metal itself. I had three versions made: copper (high purity), Ag plated, and Ag (high purity). They were made into essentially identical interconnects. Enough to do a full signal path.
Hi bear,
Thank you for sharing.
Can you please elaborate on the sonic differences between those 3 materials?
Have you tried different materials for speakers cables?
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Old 28th October 2011, 12:51 PM   #17040
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Quote:
Originally Posted by rsdio View Post
Ok, if the request is for experiences and not conclusions, then here goes:

This new wire was nothing any more fancy than 14 ga JSC Wire & Cable "Giant Speaker Wire" - since then, I put more faith in gauge than in the price tag.
Unfortunately my OOOO welding cable has gotten very expensive. 50 micro -Ohms/foot but I have not measured the L and C but I'm sure there is and L/C calculator on the web that does simple two wire transmission lines.

EDIT - Not that bad $11.60 a foot unterminated, free shipping over $250!!!. Nice, they also have OO jumper cable all made up like speaker wire for $10 a foot.

http://www.cableyard.com/RADAFLEX-We...Cable_c_1.html
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Last edited by scott wurcer; 28th October 2011 at 01:06 PM.
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