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Old 2nd February 2011, 09:36 AM   #9361
jkeny is offline jkeny  Ireland
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Quote:
Originally Posted by aardvarkash10 View Post
which bit of "not" eludes you?

.........
OK, I have been questioned, by SY, about my understanding of English & now by you - so let me deal with your use of "not".

Here's the statement you made
Quote:
"Not an outrageous claim for a conductor I don't think..."
By removing the double negatives in this statement it becomes
Quote:
"a reasonable claim for a conductor, I think"
- so you are saying that a claim was made - just using the word "not" doesn't negate it as a claim.

Last edited by jkeny; 2nd February 2011 at 09:42 AM.
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Old 2nd February 2011, 10:17 AM   #9362
Telstar is offline Telstar  Italy
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Quote:
Originally Posted by Steve Eddy View Post

What you need to look for is really a "machinist" that's willing to work with wood.

se
Yeah, but i wanted to replace the Eichmann case which is very thin, if i start with your connectors probably the machinist will have an easier job and will do 100 instead of 1000 min pieces.
One day, when i finish my amps...

cheers.
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Old 2nd February 2011, 01:43 PM   #9363
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A little back on topic, the "impulse" response of a phono cartridge. First off I don't see it being symmetric at all. Secondly on a positive impulse-like vinyl feature the stylus will leave the surface and exercise the mechanical properties of the vinyl on its return (this can be seen on actual data). Once the thermal properties of the matierial are involved the problem is much more difficult.

In researching stylus geometries I finally found an answer to something that has bothered me for years. The actual contact length for a .2mil elliptical and line contact stylus are the same (~3.5 microns). The height and therefore the contact area are very different. This is why the third octave noise intermods are not much different.

One more thing even more on topic. It is pretty easy to argue that the tip mass resonance is decoupled enough from the motor assembly that damping it with cartridge loading is not very effective. I might be wrong but I would love to see some real evidence.
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Last edited by scott wurcer; 2nd February 2011 at 01:58 PM.
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Old 2nd February 2011, 01:55 PM   #9364
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So what are you saying Scott? Have you or your associates measured what happens when a high bandwidth phono cartridge mistracks? As you should know (by now), I certainly have, and the effective risetime emulates TIM 30, AFTER RIAA EQ is applied.
At the same time: SACD, 30 ips analog recording, and some popular measurement microphones used for decades for master recording, have the same 10us risetime.
I have personally measured vinyl record mistracking and 30ips analog recording, the B&K app notes show microphone risetime, and Sony showed the risetime of its SACD playback. They are all very close in worst case dV/dt, and this sets MY design criterion for making high quality audio.
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Old 2nd February 2011, 02:00 PM   #9365
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Quote:
Originally Posted by abraxalito View Post
Science so far doesn't know how brains create sounds so a claim about sound quality can't be a scientific one. What can be scientific are claims about signals.
Indeed.
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Old 2nd February 2011, 02:21 PM   #9366
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Originally Posted by anatech View Post
Really, very interesting.

We have a cable on a web site that makes no outrageous claims what so ever, and people are digging for mud ???? Completely unbelievable! Pretty silly too.

People, the point is that when an advertisement makes a claim that implies a "secret" or wonder material so that it affects the current moving through a cable, that's when you begin looking for proof. That is the point where the advertiser should be expected to back up their claims. Clear evidence is normally expected, measurements being the preferred backup. Why measurements? Simple, they can be performed and duplicated by any other person competent enough who has access to the proper equipment.

Listening tests are also acceptable, but they are subject to more scrutiny. For an example, the NRC here in Canada has performed listening tests on loudspeakers and even arrived at a correlation between some measured parameters, and subjective responses from the listening panels. So, if the only proof and research that will be offered would be listening tests, it might be a really good idea to perform those tests in a scientifically acceptable manner. Looking at how these tests were run at the NRC would seem to be prudent.

I can't imagine anyone attempting to develop any product that makes a claim to be better in performance from all the other widgets out there to do so, without any basic research to convince them they are on the right track. Sure as heck a bank wouldn't float a business loan without something concrete to go on. They aren't that stupid.

Hi John (Keny),
Got caught throwing stones?
A person with an interest such as yours should think twice before criticizing anyone else's efforts.

After reading your web site a little, I was struck by the fact that your claims are things that can be measured. I see no valid measured information at all, and the 'scope shot you have showing the "ringing" may be caused by an improper 'scope set up. Attaching a diagram of how your equipment was set up for this test would really help assess how effective the attenuators are (or aren't). As for cable reflections, yes. I am aware of how that works.

I've also noticed that you are engaging in some personal attacks. That isn't allowed here, and that is why a recent post is no longer with us. You may address an idea or topic, but attacking a person is off limits. Not to mention that that activity is completely O.T. in this thread.

-Chris
The mathematical model for cables of all types is one of the most well understood and highest correlation formula when compared to testing data we have. I'm referrig to the "Telegrapher's Equation." It gives the lump sum parameter equivalent of the distributed parameter network of a cable.

"Listening tests are also acceptable"

I can't agree. This is a common and often repeated error, so frequently stated that I'm sure a lot of people believe it. A cable connection has a very specific electrical function to perform, namely connecting two nodes in a circuit without distorting or in any way attenuating the signal at frequencies and power levels of interest to the proper functioning of the network it's in. That is the only valid criteria to judge the merits of a cable. If cables perform their functions well and the results are less than pleasing, the place to look for problems is elsewhere. A cable is not intended to be a control element. Usually when it is used as one its stinks for that purpose although there were the rare exceptions such as when twisted wires were used as "tweaks" by functioning as small value capacitors in early television sets. Cable parameters when used as a control element give results that are unpredictable from one system to another, are not adjustable, and are very expensive. Other means are much cheaper, more predictable, and adjustable for particular circumstances.

The world standard for wire is Belden. There is nothing about wire that is known that Belden doesn't know. But as an industrial supplier they have to be cautious about their advertising claims. If they make outrageously laughable claims that can't be substantiated by test data, wild claims like cottage audiophile wire industry makes, their industrial users would laugh them out of the market, they wouldn't be take seriously about anything else they said either.

Standards for the performance of signal wire were well established by the 1920s or 1930s back when the IEEE was called the IRE (International Radio Engineer's League.) Requirements for transmission of audio, video, multiplexed telephone, various rf and data signals resulted in the development of wire that is inexpensive, reliable, and performs its function virtually flawlessly for all practical intents and purposes. The aftermarket audiophile wire industry plays on ignorance, fears, and hopes of its prospective customers to sell solutions to problems that don't exist. And it seems to work very profitably for some. In a way I have to congratulate them. They've managed to stay under the FTC's radar screen all these years. Usually it's just a matter of money but when it gets to power cords that don't have a prayer of getting a UL listing because their design is so dangerously flawed such as eliminating equipment grounding, that's when the government should really step in and take a firm hand in putting a stop to it.
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Old 2nd February 2011, 02:24 PM   #9367
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Quote:
Originally Posted by scott wurcer View Post
In researching stylus geometries I finally found an answer to something that has bothered me for years. The actual contact length for a .2mil elliptical and line contact stylus are the same (~3.5 microns). The height and therefore the contact area are very different. This is why the third octave noise intermods are not much different.
Confused/teach me.

Quote:
One more thing even more on topic. It is pretty easy to argue that the tip mass resonance is decoupled enough from the motor assembly that damping it with cartridge loading is not very effective. I might be wrong but I would love to see some real evidence.
Granted. Was it ever thought to be - my understanding was that the loading is of the output coils...like audio coupling transformer optimal secondary coil loading to kill electrical resonance/peaking response.

Eric.
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Old 2nd February 2011, 02:35 PM   #9368
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Default I Heard They Stink...

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Originally Posted by Steve Eddy View Post
Oh no. They really do smell wonderful!
se
That sounds subjective and anecdotal....Any test conditions, double blind testing, even blind testing results to substantiate that assertion, ummm claim !.

Eric.
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Last edited by mrfeedback; 2nd February 2011 at 02:54 PM.
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Old 2nd February 2011, 02:54 PM   #9369
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Quote:
Originally Posted by Soundminded View Post
The mathematical model for cables of all types is one of the most well understood and highest correlation formula when compared to testing data we have. I'm referrig to the "Telegrapher's Equation." It gives the lump sum parameter equivalent of the distributed parameter network of a cable.
Understood and agreed.
Also agree on dodgy cable electrical characteristics causing dodgy gear to exhibit varying and unprdictable sonic characteristics.
Listening tests are valuable imo in discerning problems, test gear for defining problems.
The standard lump sum parameter description does typically not include dielectric properties.
Audiophile cables sometimes make claims of dielectrics.

Agreed on Beldon - the beauty of Beldon is that their cable parameters are defined and guaranteed allowing predictable design and performance.

Eric.
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Old 2nd February 2011, 03:14 PM   #9370
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We have known for years that tip resonance is NOT effectively reduced by external electrical damping. However, listening shows that loading does effect the audio characteristics of the better MC phono cartridges. This is why we provide variable loading in upscale phono playback systems.
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