By grounding only one end of the cable's shield, EMI and RF noise is more efficiently routed to ground. - Jeromy

This is correct. It has nothing to do with ground loops other that possibly mitigating induced hum. If copper wire were directional then it couldn't be used in electronic equipment, especially with very low level signals. Diodes make good rectifiers not the wire connected to them. A certain cable reseller actually advertises this as an advantage. I want my music un-rectified please.
A differential input will take advantage of the twisted pair better than a single ended input but there is still some benefit. A single ended input can be designed for some degree of CMNR. Obviously balanced is better, I don't know why it's not used other than backward compatibility and cost. I think optical is the best, eliminates all those ground loops. Move the DACs from the 950 and install them in the 750/770. They're only about $15 a piece. Eliminates most of this discussion about interconnects in the process.
Video cables have a different set of requirements than audio interconnect cables.

What about signals that are brought into the 950 as analog? One of it's selling points is that it gives you the option of not digitizing high-quality analog signals.

Well, I guess either I misunderstood your post or I need you to explain your reasoning.

I spent many years designing and providing technical support and service for industrial / robotic control systems, and while the signals used are most decidedly NOT musical they are subject to the same laws of physics as the rest of the world. In this environment the level of electrical noise is orders of magnitude higher than experienced in a typical home.

The sole reason for ensuring the shield is only connected at one end that I'm aware of is to prevent current flow due to minute variations in ground plane potential between equipment. Other than that, ohms law implies that more connections or lower resistance to ground would be better. Or what did I miss?

Also, we had to use balanced signals as much as possible to prevent data loss or signal degradation, something that is not an option with most consumer gear.

CMNR can occur to some degree on a non-balanced system, but as I'm sure you're aware, a true balanced and shielded connection is much better.

Charlie

Charlie is definitely right about ground loops. These can be nasty little buggers in car audio, and I have even experienced ground loop noise when connecting my computer to my receiver for MP3s. A separate ground shield is great for noise rejection, but only when it doesn't induce its own ground loops. Having a "directional" cable with a single-ended ground shield is specifically designed to eliminate any potential ground loops (at least through the shield, that is). Eliminating ground loops is also the main reason for using differential circuitry – a kind of quasi balanced design.

Some high-end audio is using balanced XLR connections between components. The likes of Krell, Conrad-Johnson, etc have some balanced preamps and amps. I think one reason more audio companies don't use balanced connections is that the benefits of a balanced line cable are only fully realized on longer cable runs. If you're talking about a 0.5-meter cable, I don't think it makes much difference between balanced and non-balanced. I would be interested to know if any high-end amplifiers are using a differential or "balanced differential" input circuit instead of common-ground circuitry. I think AudioControl uses balanced differential circuitry in their equalizers and such. It seems that the benefits realized in car audio would apply to home audio as well, but I guess that home audio doesn't have many problems with ground loops or EMI.

I also wonder if RCA actually invented the "RCA" connector. Anybody know? If RCA didn't invent it, then should we rename the connector? How about calling it "Nubbin" or "The Doohickey Connector"?

Actually guys, when you are talking about digital, you are partway correct about "just" being 1s and 0s. You are also missing a VERY BIG point. It is not actually 1s and 0s, but specific voltages that are read as either an "on" or "off".

For this discussion I will use 3.3v as on! With CMOS ICs (used widely) and with FPGAs (programmable logic devices) there is an area that allows for jitter, etc and still recognize the correct 1 or 0. But, with loss, a 1 can be seen as a 0 and with noise, a zero can be seen as a 1. Exactly were the separation points are is decided by the design and manufacturing of the chips. So, cables do make a big difference. I am not saying spending $100/ft is needed, but junk will give you trash in digital. Analog is a different story, but you have to recognize that certain frequencies travel on different parts of the wire (interior, exterior)and the A-D (analog->digital) converter still has the "faults" explained above.

Sorry if I went a little deep, I tend to get deep in explainations for some reason.



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Aggie Engineers Rock

Since we are talking about audio then IEC60958 is the applicable standard. From what I gathered the rise times are so long the signal looks like a triangle wave or a sine wave. This is where the initial concern for jitter comes from. The current Cirrus Logic chip has a PLL in it's clock recovery circuit. I don't think this is an issue anymore.
On the other hand empirical testing has shown a clothes hanger worked fine. This standard is aimed at consumers and as such must work with junk. If it didn't then the non-audiophile folks would notice a problem.
For the twisted pair interconnects I can't see a significant advantage except for possible shielding. Without a diff input a twisted pair itself won't buy much. If the shield is grounded at the source then I can understand why it would work better in the car. I noticed that the Outlaw cable are twisted pair

I'll say this...after spending a few days with my 1066 pre/pro hooked up to my Parasound amp with the cheapies that came with it...when I installed the Outlaw pca cables, I immediately heard a fuller,louder sound - much better. The Outlaws are the most I've ever spent on cables...and probably will

I've been involved in audio cables as a hobbiest for decades and have spent considerable sums on cables over the years. As with many things, one quickly hits the wall of diminishing returns.

There are several products I've not seen in this discussion I would like to bring to everyone's attention.

A popular manufacturer of cable is Canare. If you proceed to their web site you can read about what makes their cable tick and importantly they publish electrical measurements to support their methods. It is popular to construct interconnects from their microphone cables. Cost is very modest. While I have made my own cables, it is very cost effective to hand the chore off to a third party. One such company is Markertek.com. For well under $20 per meter pair, you get a a very well constructed cable with substantial connectors and a lifetime warranty. They of course use the previously mentioned Canare cable. I recently ordered an assortment of stereo interconnects, 75ohm digi cable, and microphone cables using various rca and xlr terminations and I have been very happy with the quality and sound. The Canare cable is also very flexible and comes in about a dozen colors in case you feel certain shades tend to "color" the sound more. ;-)

Finally, I will also recommend a product called Stabilant-22. This is an electrical contact enhancer that has proved miraculous in a number of situations. You paint this liquid on your interconnects, op-amp pins, computer chip/memory pins, etc and it enhances the contact quality of the connection. I have used this on both audio and computer parts and had remarkable results. For example, I had an intermittent connection in the rear speakes in my Lincoln LS 2000. I took it to the dealer and they spent a day fiddling with it. After a time the problem returned. At this point I took things into my own hands and "painted" some Stabillent-22 on the amp to rear speakers connection and voila I have not had a problem since. This product is used in recording studios, hospitals, and other places worldwide. An additional bonus is that the Stab-22 also makes fitting of tight connections much easier.

Here ae some links to the products mentioned:

http://www.markertek.com/MTStore/product.CFM?BaseItem=SC3RR

http://www.canare.com/cat10pdf/p26-28.pdf

http://www.posthorn.com/Stab_2.html

-CB

[This message has been edited by ctbarker32 (edited July 02, 2002).]

[This message has been edited by ctbarker32 (edited October 07, 2002).]

Why not buy presents for our equipment if
we want to?? We do it for our cars, and even, (in a pinch), for our spouses.

I got a good giggle from a post in here somewhere in which the poster refers to premium interconnects as "Audio Jewelry"

My opinion is that entry level premium is
enough unless you have bat hearing. Just as important, is that my opinion is completely subjective. It is based on the impression that you get quality connectors and adequate wire guage and shielding.

I recently pre-wired a new home theater room with commercial grade pre-wire that you buy at a 1000 feet at a time. I was astounded to see that they had marked signal direction every foot or so along the cable. . ..As if electrons are directional. I took a few semesters of physics in college, but I must have missed the page about directional electrons. Even the most bat like listeners would be challenged (I believe) to hear a discernable difference base on which end of the wire is connected to the amplifier.


The difference IMHO between top of the line Radio Shack and entry level Monster Stuff is the marketing budget which supports the offering.

Buying the gold plated silver strands with the kung fu grip is a lot like buying modern art. If you can see, or somehow percieve value, and you have the disposable income to buy a set of 6 foot cables for the price of a good used Buick, it is OK with Eddyboy!

This is a fun thread


Eddyboy

Has anyone here wondered why wires/cables have no SPECS whatsoever?