How should star quad cables be soldered to RCA connectors?

[celroid]

I have some Canare L-4E6S Star Quad cables and I want to make two RCA cables to connect a subwoofer to my system. I looked in various other audio forums but none were clear enough on how to do this properly.

The Canare L-4E6S cable has two white wires, two blue wires and a shield. The connectors I want to use are by amphenol. I was thinking that I could solder the two white wires in the center (I think they call it a solder cup) and the two blue wires on the inside of the cable clamp. I posted a picture below showing where I was thinking the wires should be soldered.

But the question is what do I do with the braided shield, where do I solder it?

If someone can answer this and maybe include a picture of where all the wires should be soldered for a proper connection I think it will help many others who are starting out and are looking to do something similar.

 

[pma]

Star Quad cables

should be used only as speaker cables!!! Never as SE link cables.

 

[celroid]

should be used only as speaker cables!!! Never as SE link cables.

Why not? You can find many of them online prebuilt. Please provide more details as to why it's a bad idea to do this with star quad cables if I already have them and then I will consider buying different cables If it makes sense. Otherwise, please try to address the original question of the thread, thanks.

 

[VintageFlanker]

should be used only as speaker cables!!!

...or balanced interconnects also.

Anyway, star quad is not recommended for RCA, these Canare got great recommandations to make XLR cables, tho. You should use shielded Coax for unbalanced RCA.

Not an audible concern, anyway.

 

[digitalfrost]

You connect blue+blue and white+white to the same connector and the shield to the blue.

http://www.canare.com/UploadedDocuments/Cat11_p35.pdf

 

[VintageFlanker]

Why not? You can find many of them online prebuilt. Please provide more details as to why it's a bad idea to do this with star quad cables if I already have them

https://www.audiosciencereview.com/...s-getting-out-of-hand.7712/page-4#post-182056

 

[celroid]

You connect blue+blue and white+white to the same connector and the shield to the blue.

http://www.canare.com/UploadedDocuments/Cat11_p35.pdf

I modified the picture to show what I understand from your answer. Is my understanding correct?

 

[celroid]

https://www.audiosciencereview.com/...s-getting-out-of-hand.7712/page-4#post-182056

Thanks, If I got it right that post explains how the coax cable is better for unbalanced connections than the star quad cable. But then if I already have star quad cables is it worth it to spend an extra $15 to buy the coax cables? If it is not at all audible then I could just go ahead with the star quad.

 

[VintageFlanker]

But then if I already have star quad cables is it worth it to spend an extra $15 to buy the coax cables? If it is not at all audible then I could just go ahead with the star quad.

Yes!

 

[Speedskater]

Star-Quad is 10 pounds of cable in a 5 pound RCA connector.
But if you must:
1 blue wire pin to pin.
the other 3 wires and the shield shell to shell.

Best to save the Star-Quad for harsh interference situations, like on a stage with theatrical lights and smoke machines.

 

[Zek]

But the question is what do I do with the braided shield, where do I solder it?

Shield + blue wires solder together but an one end only, other end - shield free.
The common soldered end goes to the signal source.

 

[digitalfrost]

Shield + blue wires solder together but an one end only, other end - shield free.
The common soldered end goes to the signal source.

From http://www.canare.com/TopicListWithDetails.aspx?topicCategoryCode=Faq

Two conductor twisted pair cable such as L-2B2AT (or 4-cond L-4E6S Star Quad) are intended for Balanced circuits, but may also be used for Unbalanced assemblies. One of several wiring tricks, is to solder the blue conductor to the connector's center pin and the white conductor to the shield ground contact. An installer may then choose to "float the cable shield" by not soldering the overall braid (or drain wire) at one or both ends of the cable. This technique may result in better "unbalanced" circuit noise rejection.

I was actually thinking of RCA -> XLR in my original reply, I would then connect shield to RCA - for sure.

Whether blue or white go to the + pin does not matter. And if you want to float the shield, I'll leave that question to people more knowledgeable than me

 

[maverickronin]

I would recommend Canare LV-61S or Belden 8241F for DIY RCA cables. The Belden is a little more flexible but doesn't seem to be available in as many colors.

 

[H-713]

It's FINE to use star-quad for RCA cables. You won't hear a difference, and you won't measure a difference without going to frequencies in the RF range.

That L-4E6s is very well shielded. The only real downside to using it for RCA cables is that it's expensive and a PITA to terminate. That braided shield is tight and hard to unravel, and it's a lot to cram in that little connector. Still, I end up doing it all the time. Treat the shield as ground, just as you would in a usual RCA cable. Then you can use blue as center and tie white to the shield.

Seriously people, this isn't UHF we're talking about. It will work just fine and won't cause an issue. You will not measure nor hear a difference between L-4E6S and proper coaxial cable.

 

[DSJR]

Pain to solder as said above, but the cable I used for this has two the same colour hot, the two the other colour shell and the outer screen at one end only. Worked for me and that's how I do conventional mic cables into RCA's as well, one hot, t'other return/shell and screen/drain wire at one end only.

EDIT - I'm talking about these cables with RCA connectors, not XLR...

 

[H-713]

Pain to solder as said above, but the cable I used for this has two the same colour hot, the two the other colour shell and the outer screen at one end only. Worked for me and that's how I do conventional mic cables into RCA's as well, one hot, t'other return/shell and screen/drain wire at one end only.

Careful about tying one side of a balanced connection to ground. Some balanced line drivers do NOT like that. It's the correct way for a transformer output (or a solid-state output that mimics a transformer), but if the line driver just consists of an inverting amplifier driving one pin and a non-inverting amplifier driving the other, then you don't want to ground the output of one of those amplifiers. The output of the op-amp is then grounded through a 47R resistor (usually). It ends up current-limiting for part of the cycle, so you inject nonlinear currents into the ground, which can add a lot of distortion.

 

[DSJR]

Careful about tying one side of a balanced connection to ground. Some balanced line drivers do NOT like that. It's the correct way for a transformer output (or a solid-state output that mimics a transformer), but if the line driver just consists of an inverting amplifier driving one pin and a non-inverting amplifier driving the other, then you don't want to ground the output of one of those amplifiers. The output of the op-amp is then grounded through a 47R resistor (usually). It ends up current-limiting for part of the cycle, so you inject nonlinear currents into the ground, which can add a lot of distortion.

I edited mentioning my use of RCA plugs with these cables. When I used single ended preamps with my ATC monitors, I took advice from the active amp designer.

 

[sergeauckland]

I have some Canare L-4E6S Star Quad cables and I want to make two RCA cables to connect a subwoofer to my system. I looked in various other audio forums but none were clear enough on how to do this properly.

The Canare L-4E6S cable has two white wires, two blue wires and a shield. The connectors I want to use are by amphenol. I was thinking that I could solder the two white wires in the center (I think they call it a solder cup) and the two blue wires on the inside of the cable clamp. I posted a picture below showing where I was thinking the wires should be soldered.

But the question is what do I do with the braided shield, where do I solder it?

If someone can answer this and maybe include a picture of where all the wires should be soldered for a proper connection I think it will help many others who are starting out and are looking to do something similar.

Can I be awkward for a moment, and say you shouldn't solder star-quad to an RCA plug. Star-Quad is a microphone cable, for use in extreme environments and is designed for XLR connections, not unbalanced RCA. It has high capacitance, so apart from being a pig to solder into an RCA, will also possibly roll-off high frequencies, which I accept is no problem for a sub-woofer.

Even if you have some Star-Quad cable to hand, keep it for its proper function and just buy some RG6 or RG59 cable which costs well under £!, $1, €1 a metre in any DIY store. It's often sold as satellite antenna cable. RG6 is better screened, but stiffer, so I usually use RG59 for my DIY interconnects.

That will be a lot easier to wire into an RCA.

S.

 

[Chrispy]

Why would you use this star quad stuff for speaker cables, tho?

 

[sergeauckland]

I edited mentioning my use of RCA plugs with these cables. When I used single ended preamps with my ATC monitors, I took advice from the active amp designer.

Going from unbalanced RCA to balanced XLR is very easy, it's unbalancing a balanced output that's more difficult. Connecting Pins 1-3 is fine for the input, but shorting out an output is a problem. The ONLY time this can be done safely is with a fully-floating transformer-coupled output (possibly also the active equivalent, but I'm less certain about it being universal) Otherwise, the safest way is to leave XLR pin 3 floating and go between pin 1 (ground) and pin 2 (signal).

S.