[Letmebefrank]

Huh, negative is ground.

Positive and negative in transducers are for phasing, you don't connect the output of an amplifier to earth or you will ruin it.

 

[Paladin79]

Single entry headphones share a common ground, and the cable can certainly be two conductors and a shield with drain wire, thus the shield is ground. Fostex and lower end Beyerdynamic use this.

Twisted pair is a form of shielding as is a physical shield. Some of the better cables use one twisted pair and a shield or even a double shield, those cables are not very flexible. Star quad is often used with dual entry headphones and there is a spiral twist, the shield should not be used as ground IMHO since two separate grounds already exist and an additional ground would form a loop and act like an antenna.

Good reply Frank. You should not confuse earth ground with ground potential or a signal that is less positive than another.

 

[hoskoau]

Single entry headphones share a common ground, and the cable can certainly be two conductors and a shield with drain wire, thus the shield is ground. Fostex and lower end Beyerdynamic use this.

Twisted pair is a form of shielding as is a physical shield. Some of the better cables use one twisted pair and a shield or even a double shield, those cables are not very flexible. Star quad is often used with dual entry headphones and there is a spiral twist, the shield should not be used as ground IMHO since two separate grounds already exist and an additional ground would form a loop and act like an antenna.

Thanks, I am use to using star quad for balanced mic cables. But we always tie two of the conductors together, it thought it was designed for that.

I just made a cable for my single entry AKG K712s using Mogami mini quad. I used the shield for ground, tied two conductors for left and the other two for right.

 

[hoskoau]

Positive and negative in transducers are for phasing, you don't connect the output of an amplifier to earth or you will ruin it.

Ground isn't earth.

 

[Paladin79]

This is an interesting topic but I have an hour drive before I can answer again. A shield is the second conductor on coaxial cable and the third on standard microphone cable. The question was "why is it not used" and my answer is, sometimes it is.

There several types of grounds and that subject can be tricky. I can only think of four or five types off the top of my head. Driving soon, enjoy the topic!

Earth is most certainly a ground and if the chassis of an amp is at ground potential and the sleeve of a connector (signal ground) is attached to that same point, it is going to earth ground. A balanced output does not share a common ground so I would think the path is not so direct.

As far as using two wires for left channel and two for right and the shield for ground that should work and you are increasing the conductor size going to each channel. What you do not want to do is come out of a balanced output on an amp and go to a TRS connector and combine both negatives.

This article should help a bit...

https://robrobinette.com/Push-Pull_Vs_Single-Ended_and_Balanced_Vs_Unbalanced.htm

When you are using dual entry headphones and the cable uses a TRS connector and if you are connecting that to an unbalanced amp, you have a more obvious ground connection. If you are hooking to a balanced out put and use the proper four connection cable those same connections in the headphones are positive and negative. This is a round about way of saying most everything I have heard here is correct, it is the balanced and unbalanced application that can change things.

 

[Allanmarcus]

You could use the shield as the common, but if you also use one of the conductors, you have a "loop" you are running one insulated wire and a second (the shield) outside the insulation. That might cause an issue.

The second issue is separation. for a balanced cable, there is no common. each channel has a left and right + and -. For single ended there is no "-", there is hot and common. the common is literally common between left and right channels. For balanced, the - is not common between left and right channels.

Hope this makes sense.

 

[Paladin79]

it makes sense to me but then I work with the stuff lol. Using the word "common" opens up another can of worms. Here is an article that talks about types of grounds.

https://www.allaboutcircuits.com/technical-articles/an-introduction-to-ground/

Also something Allan will be aware of, earlier I was talking about string and such being used in some cable to give it a round shape. They do not use such things in Ethernet cable so you will see a wavy appearance when using twisted pair. String can also be used to help strengthen a cable so you do not damage the jacket or conductors when pulling it. I have some audio cable where it is obvious it contains twisted pair by looking at the outside jacket, some of the more expensive cable looks perfectly round and conforms to connector openings better. You will see it yourself if you use heat shrink or mesh on twisted pair, the mesh probably hides the shape a little better.

 

[kwatch]

I'm planning to make a digital coaxial cable using Belden 1694A. What do I use to terminate each end? Can someone recommend me one I can use?

 

[Paladin79]

Such cable can be terminated depending on usage, BNC connectors, F connectors or most likely RCA connectors. For audio use and digital audio go with RCA connectors. My people use Canare connectors but the tools can be pretty pricey so your best bet is to use Neutrik/Rean connectors. There are two conductors in such coaxial cable, center conductor and braided shield. Attach shield to ground and center conductor to center post of the RCA connector. Here are some that would work well. These are solder type connectors.

http://www.tecnec.com/Product.asp?c...&baseitem=NF2CB-2&search=0&off=0&showreturn=0

http://www.tecnec.com/Product.asp?c...aseitem=NYS373-BK&search=0&off=0&showreturn=0

I also like these Amphenol RCA connectors

https://www.alliedelec.com/amphenol-audio-acpr-red/70400416/

You can use the 1694A for audio interconnects, Subwoofer cables, Digital audio cables (SPDIF), HD/SDI and video but your easiest use would be audio interconnects, but just remember down the road that cable is capable of other usages if you so desire. It will do low frequencies but has been sweep tested up to 4.5 gigahertz. The engineering staff at a local university use that series cable mini rg 59, RG 59, and RG 6 (the 1694A) for most any coaxial cable usage and I have built 500 foot cables with it that were used for filming such things as the X games.

Tom

 

[Paladin79]

Here is the first connector I mentioned, they are Neutrik's top of the line I believe. I am using a coaxial cable that is laid out like the 1694a. This is silver plated ofc wire with a clear pvc jacket and stranded center conductor instead of solid but soldering technique is very similar between this and 1694A. I am in the process of building a couple sets of these to match up with a bottlehead crack done in silver and black (carbon fiber and black lacquer).

 

[Letmebefrank]

That BH Crack is beautiful Tom.

 

[Paladin79]

You are most kind Frank. I am staying away from lacquer on future projects, this was a lot of work lol, the cables are easy.

 

[kwatch]

Such cable can be terminated depending on usage, BNC connectors, F connectors or most likely RCA connectors. For audio use and digital audio go with RCA connectors. My people use Canare connectors but the tools can be pretty pricey so your best bet is to use Neutrik/Rean connectors. There are two conductors in such coaxial cable, center conductor and braided shield. Attach shield to ground and center conductor to center post of the RCA connector. Here are some that would work well. These are solder type connectors.

http://www.tecnec.com/Product.asp?c...&baseitem=NF2CB-2&search=0&off=0&showreturn=0

http://www.tecnec.com/Product.asp?c...aseitem=NYS373-BK&search=0&off=0&showreturn=0

I also like these Amphenol RCA connectors

https://www.alliedelec.com/amphenol-audio-acpr-red/70400416/

You can use the 1694A for audio interconnects, Subwoofer cables, Digital audio cables (SPDIF), HD/SDI and video but your easiest use would be audio interconnects, but just remember down the road that cable is capable of other usages if you so desire. It will do low frequencies but has been sweep tested up to 4.5 gigahertz. The engineering staff at a local university use that series cable mini rg 59, RG 59, and RG 6 (the 1694A) for most any coaxial cable usage and I have built 500 foot cables with it that were used for filming such things as the X games.

Tom

There is a big price difference between Rean NYS373 and Neutrik NF2CB. Will there be a SQ difference between them?

Thanks.

 

[Paladin79]

I doubt you would hear any difference to be honest.

There is a difference but it has more to do with the construction of the connector and what happens when you plug them in and out. If you are going to just plug the cable in and leave it, the less expensive one should be fine. Today I happened to be using the higher end connector because of the cable size I was using. 1694A is probably just over a quarter inch in outside diameter.

 

[MikeJSmith]

Hey, I’m sure everyone already has this figured out but I thought I’d share the way I’ve been sleeving some 26awg wire with paracord.

I tried the inching along like a caterpillar but that was soul destroying so I got some thin, hollow brass tubing from a hobby store.

Then stripped a couple of cm of the wire and soldered it into the tube. It was easiest using the heat gun attachment to my gas soldering iron.

Then it was super easy to thread the tube through the paracord. Took less than 5 minutes for each 1.2ish metre wire, including soldering time.

Hope this helps someone!