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DIY XLR Cables


Saif and Sound

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"Starquad" is not a brand, but a cable configuration that uses four conductors twisted around the axis of the cable, maintaining their order inside the cable. When using starquad cable in a balanced circuit, imagining that the conductors are numbered in order 1, 2, 3, & 4, the two even conductors are paired together and the odd connectors are paired together when attaching to the connetor. As an aid, manufacturers often color-code the even conductors one color and the odd conductors are another conductor. So, in the case of XLR cables made of starquad wire with conductors that are white and conductors that are blue, the whites are connected to either pin 2 or pin 3, and the blues are connected to either pin 2 or pin 3. It makes no difference which color pair goes to pin 2 and which goes to pin 3. It only matters that the conductors of each color stay together and connect to the same pin, and are on the same pin number at both ends of the cable. Blue to 2 or blue to 3; it makes no difference at all. Just be sure to treat both ends of the cable the same, and be sure to put the shield on pin 1. As with all general purpose balanced cables using XLR connectors, also connect pin 1 to the grounding tab.

Regarding what's been called, in this thread, "the BBC standard" of pairing red/white, blue/green: Some manufacture color code their starquad cables with four different colors, and will provide specs about which colors to pair together for a balanced starquad circuit. One very good reason to use four different colors for these cables is for when using them for something other than the balanced starquad configuration, such as when four independent conductors are needed (control cables and balanced stereo cables are examples).

It should be said that the starquad scheme is not without fault, and that long runs will degrade the high frequencies in an audio signal. However, it should also be said that this degradation would typically only be a factor with unusually very long runs, the affects of which would usually be out-weighed by the benefit in noise reduction.

Glen Trew

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As with all general purpose balanced cables using XLR connectors, also connect pin 1 to the grounding tab.

Glen Trew

Hey, Glen, care to weigh in on the "shield tied to shell" of the connector issue? I have heard all the discussions, the reasons why it must be done, both ends, the reasons it should never be done, the dangers of electrocution when th shell makes contact, etc., etc. Why don't you be the one who finally gives the definitive answer.

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I decided to connect the connector shell and the cable shield because for my use most grounds are "floating" in that my rig is powered via a battery and its pretty rare that I would need to connect two systems that have a different ground potential  (ie: two systems plugged into mains AC that are separated by some physical space). 

Also, most of the gear I use is of modern design and not as likely to create a ground loop.

Also, I've emailed both PSC and Sound Devices regarding this and they both recommended connecting pin1 and the shell.

To me, it just makes sense.

That said I've never encountered a problem that was solved by disconnecting the shell.

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I will not pretend to know all the pro's and con's of jumping the ground to the connector controversy but I decided to stop doing it after a mixer with more experience then I'll ever achieve said to me that he wouldn't do it outside of a closed recording studio.  His reason - if that connector touches a stray electrical current, hi-voltage electricity will travel up that cable and into your gear and also into you possibly.  When I asked what type of stray current is around the set he mentioned faulty electrical boxes the electricians might put out or even other carts, video or dit, that might have a grounding problem.  Sounded good so no more jumper to connector for me. 

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" I've never encountered a problem that was solved by disconnecting the shell. "

I have!

" most grounds are "floating" in that my rig is powered via a battery "

as long as you do not connect anything connected to you, to anything connected to another power source (especially AC), as then you have ground loops...

and...

" connector touches a stray electrical current,(looking for ground) hi-voltage electricity will travel up that cable and into your gear and also into you possibly. "

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I decided to connect the connector shell and the cable shield because for my use most grounds are "floating" in that my rig is powered via a battery and its pretty rare that I would need to connect two systems that have a different ground potential  (ie: two systems plugged into mains AC that are separated by some physical space). 

Also, most of the gear I use is of modern design and not as likely to create a ground loop.

Also, I've emailed both PSC and Sound Devices regarding this and they both recommended connecting pin1 and the shell.

To me, it just makes sense.

That said I've never encountered a problem that was solved by disconnecting the shell.

Hey Derek! Funny that you should say that about PSC and Sound Devices. That contradicts my research when I contacted Neutrik and they firmly advised me not to connect anything to the shell of their XLR connectors. LOL! But both ways, I've never come across any ground issues. And I connect all my cables without pin 1 to the shell. However, I know that my K-Tek boompole internal cable does have the shell connected on both ends.

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I would like to know more about Star Quad cables.

I wire my cables with two conductor and braided shield ground only. From my understanding regarding the cables I use is that both conductor cables are twisted symmetrically along it's length and that both lines are both equal in resistance, which in turn rejects or atleast minimizes unwanted common mode signals.

But what are the benefits of using Star quad cables where you merge two corresponding conductors each to pin 2 and pin 3?  How does this wiring function differently from two conductor for hot/cold balanced lines? If too long an answer, please refer me to some good articles to read up on the subject if available? Thanks!

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Hey Eric, I just wanted to say - In no way did I mean to disregard/disrespect by calling it hogwash. t Was not a sly at you at all, it was simply meant to say the color dont matter.Your post actually taught me a thing or 2 about cable;

DIY till I die..

No problem, no offense taken. I've mostly followed the manufacturers directions figuring they know a lot more about their product than I do. My Star Quad wiring convention has been the same as Canare's, "White Hot,  Blue Cold". I'm sure over the years I've wired Star Quad "Blue Hot, White Cold" but I'm not going to check 1500' of various lengths since they all work just fine. I'm still trying to figure out how they get all that sound down those little wires ;-))

Eric

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  • 5 weeks later...

I've also purchased Canare cable in bulk from Pacific Radio in Burbank: (818) 556-4177. (Note that they moved about five blocks from the old place, but are still very close to the Burbank Airport.)

When I'm in a mad rush and don't have time to cut and solder cables myself, I usually get them from ProAudio LA in Silverlake: (323) 319-5936. All Canare cable, Neutrik connectors, fairly inexpensive. Nice people.

Be sure to get the Canare L-4E6S cable -- not the thinner L-4E5C cable, which is intended for panel (permanent) mounting. I haven't tried the 110 ohm star-quad AES digital cable.

--Marc W.

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Go for it! The satisfaction of burning through a 100m (328') roll of starquad is imense!

Saif,

There are lots of places in LA to buy bulk: Pacific Radio, Electronic City... Neutrik connectors can be bought locally at LSC, Coffee, also. On line for Neutrik is Markertek. BTW after coaxing about twenty years ago, Markertek started manufacturing audio cables using Canare Starquad, Neutrik Black and Gold connectors, lead free silver solder, and their quality (there are people there who sit and make XLR cables for a living...) is VERY high. Not too pricey either. I still make every cable I can (not counting those damn Lemos and tiny Hiroses!) Are you in 695? If you are there is a great soldering clinic offered.

As to cable fab. I'm a fan of starquad. It works. I so rarely run more than 250', I never experience the high freq attenuation that occurs at greater distances. For long, permanent runs I use two conductor foil shielded cable. If the cable isn't going to move, foil rocks at 100% shielding. I can't remember the last time I had a hum issue induced into a cable. I've always used the "blue to two" mnenomic, as it works with both Canare and Mogami. And lastly, I don't connect cases at all.

This is an excerpt from another thread on this site, my reply:

My two cents: I do not disagree with ANY of the advice in this thread, however... There is a MAJOR difference between the Mogami offering and the Canare and Belden. All three are "quaded", and Glen's explanation is accurate, but there is another factor. The shielding scheme in the Canare and Belden is braided (offering >95% shielding), while the Mogami shielding is "served" or simply put, completely wrapped around the conductors (offering 100% shielding). The served shield is an advantage in offering greater protection from RFI interference, yet if the cable is subjected to constant coiling/uncoiling the served shield tends to separate, making the cable more susceptible to ALL outside interference. In my package, I use the Mogami cable for all PERMANENT interconnections on the cart, where once in place they are stationary, but use Canare for all cables used on the set and leading to the cart - any cables that are wrapped/unwrapped over and over again. Additionally, the Canare has the characteristic of remaining incredibly flexible in very low temperatures; I have used both single pair and four pair Canare in temperatures approaching -40º and it stayed flexible as others snapped, cracked, and died.

Jay

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Where is one able to buy thin yet soft and flexible audio cable in bulk? I am talking about the diameter thin enough for 2 cables to go into a TA5F like the cables used for the Zaxcom QRX100 and Lectrosonics SRa5P. I am in South Africa and such a cable just doesn't exist. I've tried our local supplier of Belden and Canare cables but no joy on any front. I want to lighten the load and neaten up the spaghetti in my bag. Does anyone know which brand of cable is used for the Kortwich cable assemblies seen in the picture

Any leads would be greatly appreciated!

---Sebastian

post-22-0-95150000-1309439052.jpg

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Mogami make the very thin flex-shielded cable used in the lectrosonics ta5f - 2 x XLRm. Here's a link to the relevant section of their site: http://www.mogamicable.com/category/bulk/ultra_flex_mini/

Thanks for that. There is a Mogami agent here in South Africa so will try him.

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Sebastian,

Have you looked at Belden 1804A Mini Star Quad?

http://www.belden.com/techdatas/metric/1804A.pdf

http://www.belden.com/techdatas/english/1804A.pdf

It is the smallest diameter cable I work with, though I think you would be hard pressed to get two pieces into a TA5.

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Sebastian,

Have you looked at Belden 1804A Mini Star Quad?

http://www.belden.com/techdatas/metric/1804A.pdf

http://www.belden.com/techdatas/english/1804A.pdf

It is the smallest diameter cable I work with, though I think you would be hard pressed to get two pieces into a TA5.

If you cut off the rubber boot end and drillout the plastic back piece you can get 2 pieces in a TA connector. OTOH getting them both under the cable clamp fingers is not easy.

Eric

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  • 4 weeks later...

Does any one know what the model or part number for the thin Mogami cable used by Lectrosonics/ Zaxcom is? I have the link to the list but don't know which one it is. Any help is gladly appreciated.

http://www.mogamicable.com/category/bulk/ultra_flex_mini/

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