Making my own RCA -> XLR cables

[Jdunk54nl]

I need want to make some RCA -> XLR cables. I have some odd lengths that I can't buy and thought this would be fun. I will be using these for my AVR to my Crown amp as well as some active monitors with XLR ins from a dsp with RCA outs. I have read nearly ever post here on this topic and most just stop without any final decision.

Here is what I am thinking of using:

Cable: Either Mogami w2549 ($0.92/foot) or Canare LE46S Star Quad Cable ($0.59/foot). Leaning towards the star quad due to it being cheaper. Which one would you choose?

Connectors: Thoughts on these or other suggestions?
Neutrik XLR Connectors
Rean RCA connectors.

I see these two diagrams posted about how to connect them often: One has the shield floating on the RCA end and one has it connected. Which one is better?

From Rane no shield on RCA end: https://www.ranecommercial.com/kb_article.php?article=2107

From Hypex NC400 documentation: Shield on RCA end
https://www.diyclassd.com/documenten/download/860
https://www.hypex.nl/img/upload/doc/an_wp/AN_Legacy_pin_1_problems.pdf

Are these connection similar to the monoprice style. Note: The pin 1 and 3 are soldered together on the XLR end of the monoprice cables. I purchased one and verified this. This was the difference I see between this and the hypex configuration. I don't know if that actually makes a difference as it would be connected on the RCA end to make a closed loop anyway. But this gets into the directional cable ideas.

 

[Speedskater]

Wait! XLR to RCA is different than RCA to XLR.
XLR to RCA is tricky because there are three & a half types of XLR outputs and no single type of adapter will work for all three.

 

[Jdunk54nl]

Wait! XLR to RCA is different than RCA to XLR.
XLR to RCA is tricky because there are three & a half types of XLR outputs and no single type of adapter will work for all three.

My bad, it should be RCA -> XLR. I don't know why I put the reverse. I fixed it in the title and post #1

 

[solderdude]

You just beat me to it.

RCA to XLR is the bottom picture of the OP
Pin 1 & 3 should be connected when using an XLR INPUT from unbalanced source, certainly when the XLR is on a stereo device.
When using XLR outputs pin 1 and 3 should NEVER be connected together.

 

[earlevel]

Your AVR has only XLR/balanced outs? Not much of an advantage if you're going to unbalanced ins.

First, if you're going from XLR to RCA, the Rane article you cite has a different wiring for that (diagram 6). Take another look. note that pin 1 and 3 are connected, like your Monoprice cables. The difference is the shield connection. The cable is obviously transporting high signal levels, so the shield connection on both ends doesn't have the importance it would with mic levels. Ground loops are the bigger threat, so I'd go with the Rane suggestion.

You don't really need star quad, since this is not low-level (from a microphone). I bought a spool of Mogami Neglex 2534 (star quad version of the Mogami you're looking at) decades ago, one of the great decisions to have on hand. It's been a long time since I've touched Canare, I recall it being OK, but not in the league with Mogami. The Mogami is extremely supple, it gives a feeling of satisfaction every time you need to connect or route the cable, you'll never be sorry.

The Neutrik XLR is the standard by which all should be measured, excellent.

 

[Jdunk54nl]

Just to clarify (which I already corrected) I messed up with saying XLR -> RCA. I need the reverse of RCA -> XLR, which I corrected the title and post #1 to say.

My AVR has rca outs and my desktop dsp only has RCA outs. Everything I currently have only has RCA outs. So I need to make RCA to XLR cables as all my external amps have XLR inputs. The crown amp has rca but it has a noise issue that I think a proper RCA -> XLR would fix. The active monitors are jbl 305p mkii's which have XLR or TRS input.

 

[earlevel]

Just to clarify (which I already corrected) I messed up with saying XLR -> RCA. I need the reverse of RCA -> XLR, which I corrected the title and post #1 to say.

OK, RCA to XLR is pretty straight-forward—use the Rane diagram you were looking at.

 

[Blumlein 88]

Nothing wrong with making your own, but honestly I'd just buy some ready made.
https://www.amazon.com/Monoprice-XL...ds=monoprice+rca+to+xlr&qid=1607369180&sr=8-3

These are not the most supple, but well shielded and work fine. Available in so many lengths I can't imagine they wouldn't work for you. I've used them several times going RCA to XLR.

If you are determined to make your own, then just ignore this. Not trying to tell you that you shouldn't make them.

 

[Jdunk54nl]

RCA to XLR is the bottom picture of the OP
Pin 1 & 3 should be connected when using an XLR INPUT from unbalanced source.

The pin 1 and 3 thing is where I get confused here. None of the diagrams show them being connected on the xlr side.
Rane’s diagram doesn’t appear to have 1 and 3 connected at all.
Hypex does on the rca side (shield and ground soldered on rca)
Mono prices cable did on both sides (shield and ground on rca and pin 1 and 3 physically soldered together.

 

[Wayne A. Pflughaupt]

Cable: Either Mogami w2549 ($0.92/foot) or Canare LE46S Star Quad Cable ($0.59/foot). Leaning towards the star quad due to it being cheaper. Which one would you choose?

I’ve used both and like the Canare better. I haven’t found anything Mogami offers that makes it worth nearly double the price. Plus, the Mogami is not as pliant as the Canare. At least the stuff I used a few years ago wasn’t (I think it was the same # as what you linked).

Actually, if you’re going Canare, no reason to get the star-quad. The two-conductor L-2T2S is just fine, and even cheaper than the star quad.

The only downside to the Canare, as far as DIY is concerned, is the brutal braided shield. You can find tips on how to deal with it in my DIY cables article.

Connectors: Thoughts on these or other suggestions?
Neutrik XLR Connectors
Rean RCA connectors.

Best RCA ever. For XLRs I prefer Switchcraft, but there’s absolutely nothing wrong with Nuetrik.

...all my external amps have XLR inputs. The crown amp has rca but it has a noise issue that I think a proper RCA -> XLR would fix.

I’m sure the XLR connectors on those amps are combi-jacks, which accept a 1/4" plug in the center. IMO makes more sense to just go RCA to 1/4" TS than XLR.

Regards,
Wayne A. Pflughaupt

 

[Rock Rabbit]

For a noisy environment use Rane config, but for 305 a simple adapter on the RCA end (XLR cable, female connector) works fine

The adapter ties GND and COLD terminals

 

[solderdude]

The pin 1 and 3 thing is where I get confused here. None of the diagrams show them being connected on the xlr side.
Rane’s diagram doesn’t appear to have 1 and 3 connected at all.
Hypex does on the rca side (shield and ground soldered on rca)
Mono prices cable did on both sides (shield and ground on rca and pin 1 and 3 physically soldered together.

The bottom one does have 1 and 3 connected via the screen to RCA shield and from RCA shield to 3.

Your signal needs to be between common (pin 1 XLR) and + signal (pin 2) and the - input (pin3) should be connected to common (pin1)
The bottom drawing does this but via the screen and not directly.
You can also connect 1+3 to the screen of the RCA via 1 wire, connect signal via the wire to pin2 and connect the screen of the wire to screen of XL and screen of RCA or only connect the screen to XLR and not RCA.

The Rane version does not and can be used for connecting a single device such as an active speaker.
In this case the XLR receives just half the voltage it would have received compared to the bottom drawing.
When you use it from a stereo source (grounds tied together) to XLR inputs from a stereo amplifier you are tying the - signal inputs together but not the grounds.

For your purpose build the bottom one if you want to build one yourself.

 

[Blumlein 88]

For a noisy environment use Rane config, but for 305 a simple adapter on the RCA end (XLR cable, female connector) works fine
View attachment 97855View attachment 97856
The adapter ties GND and COLD terminals

This is a good option I started to mention. Then you can just use XLR cables.

 

[earlevel]

Plus, the Mogami is not as pliant as the Canare. At least the stuff I used a few years ago wasn’t (I think it was the same # as what you linked).

Surprising...it's been decades since I've used Canare, and it was in pre-built cables, but Mogami is known for being supple—if you search on that word with Mogami, it pops up quite a bit. And with the Canare having a braided cable, I'd be surprised if it was more so than the Mogami. But maybe in a different way...(besides the star quad Mogami, I have a half-spool of their 8-cable snake bought at the same time and used for a few things that's amazingly supple for 8 x two-conductor plus shield in a jacket.

I'm sure Canare is fine, not disagreeing, just registering my surprise about the flexibility issue.

For XLRs I prefer Switchcraft, but there’s absolutely nothing wrong with Nuetrik.

Swtichcraft also excellent—for people who prefer the Neutrik, it's usually for the strain relief design, I think.

 

[Cbdb2]

More info.

https://www.jhbrandt.net/wp-content...tion_of_Balanced_and-Unbalanced-Equipment.pdf

 

[Cbdb2]

Surprising...it's been decades since I've used Canare, and it was in pre-built cables, but Mogami is known for being supple—if you search on that word with Mogami, it pops up quite a bit. And with the Canare having a braided cable, I'd be surprised if it was more so than the Mogami. But maybe in a different way...(besides the star quad Mogami, I have a half-spool of their 8-cable snake bought at the same time and used for a few things that's amazingly supple for 8 x two-conductor plus shield in a jacket.

I'm sure Canare is fine, not disagreeing, just registering my surprise about the flexibility issue.


Swtichcraft also excellent—for people who prefer the Neutrik, it's usually for the strain relief design, I think.

The star quad is microphone cable, thus the more durable, stiffer, (but less effective) braided shield. Its also more work soldering. For interconnects I prefer the mogammi, nothing to do with audibility. Get the 2pair cable.

 

[Jdunk54nl]

The bottom one does have 1 and 3 connected via the screen to RCA shield and from RCA shield to 3.

Your signal needs to be between common (pin 1 XLR) and + signal (pin 2) and the - input (pin3) should be connected to common (pin1)
The bottom drawing does this but via the screen and not directly.
You can also connect 1+3 to the screen of the RCA via 1 wire, connect signal via the wire to pin2 and connect the screen of the wire to screen of XL and screen of RCA or only connect the screen to XLR and not RCA.

The Rane version does not and can be used for connecting a single device such as an active speaker.
In this case the XLR receives just half the voltage it would have received compared to the bottom drawing.
When you use it from a stereo source (grounds tied together) to XLR inputs from a stereo amplifier you are tying the - signal inputs together but not the grounds.

For your purpose build the bottom one if you want to build one yourself.

The bottom one is the monoprice wiring which I wasn't sure if that was following the hypex diagram due to pin 1 and pin 3 connections.

Monoprice clearly shows their connections at both ends

Hypex shows it at the rca end, but then it states only if the rca shell is bonded to the chassis to connect it there in the description. At the XLR end it looks like 1 and 3 are not connected and 1 is connected to shield only and 3 is connected to - input wire only.

Even this hypex doesn't show pin 1 and 3 being connected at XLR end:

I am probably over analyzing these in reality...but I just want to build them right.

Eventually I will be upgrading to hypex or purifi amps so I want to build proper cables (or possibly buy but the monoprice ones don't seem to be wired 100% like hypex suggests).

 

[solderdude]

It clearly states 'the RC network can usually be shorted' means you can simply tie RCA ground to pin 1 (shield) and RCA ground (wire) to pin 3 and signal to 2.
Here too pin 1 and 3 are both connected to common/ground.

 

[earlevel]

A couple of other notes: The capacitance of the Mogami is far lower than the Canare (even Mogami star-quad vs Canare star-quad, but more so on the 2549 single conductors). Star quad isn't going to have an advantage for your use, and it's easy to solder connectors with the two-conductor plus shield than the quad. (XLRs aren't so bad with quad, but with phone and RCA plugs quad is tight to work with.)

PS—I like the idea of the adapters, to a degree, but they most often create a bad leverage point for stressing the connector/cable. So it depends on what's going on behind the unit, whether it's acceptable.

PPS—The capacitance isn't an issue with the length you'll be using and the impedance, I shouldn't have even mentioned it—was more about how people might compare the two for certain uses than anything to do with your use.

 

[Jdunk54nl]

It clearly states 'the RC network can usually be shorted' means you can simply tie RCA ground to pin 1 (shield) and RCA ground (wire) to pin 3 and signal to 2.
Here too pin 1 and 3 are both connected to common/ground.

I guess I am missing where it shows them connected at the XLR side. I also assumed that shorting the RC network just meant to eliminate that, not to connect pin 1 and 3 together.

So eliminate what I did in red and just make it a wire, but it doesn't appear 1 and 3 are connected here. At least I would think they would make that clear if it was...they did on the RCA side at least. Does this even make a difference on the XLR side.

Again, this was my issue with the monoprice cables because they did have the XLR pin 1 and 3 physically soldered together and the RCA shell soldered to shield and -input.. Does this soldering at the XLR side and RCA side make a difference to just having them soldered at the RCA side?


In all of the threads here that I have read, the hypex document kept coming up (at least the most recent ones) as the way to make your cables. It is what benchmark, march audio, and a few other companies do. I just am not 100% sure if they are actually soldering pin 1 and 3 and if it makes a difference. Why wouldn't hypex have that connection shown in their diagram if it was supposed to be?

I plan to update to hypex or purifi amps so I want to do these right.