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Proper cable to join RCA to XLR balanced, help needed

Miguelón

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Hi everybody!

I need a good (in the sense of 2 wires inside and shielding apart) cable to feed a Genelec active monitor (XLR input) from WiiM Ultra RCA.

I was told by other member that many cables on the market are improperly connected and don’t benefit from the 30 dB protection against interferences, do anyone know a concrete model which can be bought in Europe?

Another question, do impedance cause audible impact? RCA input has 10.000 ohms in my monitor, but XLR has 5.000 (has that something to do with the 2 parallel inputs or with the double voltage in balanced outputs?). Do a regular unbalanced signal feed twice the current to the circuit? Is better to match the impedance with some active or passive adapter like a DI Box?
 
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This cabel is beeing sugested here many times: Monoprice 104777 XLR-Cinch.
 
Genelec recommends an XLR-RCA cable with XLR pin 2 -> RCA tip; XLR pin 3 -> RCA sleeve; XLR pin 1 (shield) -> RCA sleeve. Thus, the XLR’s pins 3 and 1 are tied at the RCA.

All the other stuff you mentioned is of little or no concern. Just connect your gear and enjoy it.

The Monoprice cable mentioned will work fine, but with 16ga cable instead of the usual 22-24, it’s freakin’ gnarly.

Regards,
Wayne A. Pflughaupt
 
IIRC, someone once reported here that Monoprice's pinout diagram doesn't reflect the actual product and that their cable, like most others, shorts XLR1+3 inside the XLR plug.

Probably a good idea to double-check the construction with a multimeter.

If the impedance of RCA Signal->XLR2 ≈ RCA GND->XLR1 and XLR1->XLR3 ≈ 2x the above, then it's likely that the construction is as advertised.
 
IIRC, someone once reported here that Monoprice's pinout diagram doesn't reflect the actual product and that their cable, like most others, shorts XLR1+3 inside the XLR plug.

Probably a good idea to double-check the construction with a multimeter.

If the impedance of RCA Signal->XLR2 ≈ RCA GND->XLR1 and XLR1->XLR3 ≈ 2x the above, then it's likely that the construction is as advertised.
Nice trick! Obvious but I didn’t think it… sadly I don’t have a multimeter.

Why, if the topology by utilizing shield RCA to 1 and 3, pin to 2 XLR is more advantageous not all cables use it?

BTW, once watched the MonoPrice cable in Amazon, the algorithm suggested me other with same design. Probably the AI identified the diagram.


This has a 3 meters length.
 
Why, if the topology by utilizing shield RCA to 1 and 3, pin to 2 XLR is more advantageous not all cables use it?
Because that requires 2-core wiring.

If you short XLR1+3 inside the XLR plug, then you can use single core wiring which is cheaper.
 
Because that requires 2-core wiring.

If you short XLR1+3 inside the XLR plug, then you can use single core wiring which is cheaper.
Honestly, I considered that possibility but discarded it by absurd, I thought “is impossible that the single reason is saving some copper”.

I’m so naive, even now I think builders do it for ecological motivation… :)
 
Honestly, I considered that possibility but discarded it by absurd, I thought “is impossible that the single reason is saving some copper”.

I’m so naive, even now I think builders do it for ecological motivation… :)
Not in the case of the Monoprice cabled mentioned, with its insane 16ga center conductor. You could easily do a standard 22-24ga two-conductor cable and have copper left over!

Regards,
Wayne A. Pflughaiupt
 
Not in the case of the Monoprice cabled mentioned, with its insane 16ga center conductor. You could easily do a standard 22-24ga two-conductor cable and have copper left over!

Regards,
Wayne A. Pflughaiupt
Thanks again for your recommendation. I noticed that are little bit short but have a female to male XLR to add in one side because the source is not at the center, I purchased a pair.

Also one of my speakers, the G Three, doesn’t sound so good whatever the connection I put in it.

It is some extra decibels louder in low region, and need a correction by the PEQ but is not as flat as the 8030C which is just aside. It’s tonality is warmer, and because I owned a twin which stopped to work and sent it to dealer, I think G Threes are slightly “tuned” to home actual tastes.

My instruments are not the bests to make a serious post but I will try to get a Behringer mic or a Unik: definitely by throwing it pieces that I recorded myself or I know well it sounds flatter.

In the same position G Threes seem as “inflated” by the low end, in detriment of clarity on the mid side.

Due to some number of members that are doubting between one or the other, I think can be useful to make a little comparison, specially because G Threes is more expensive by 200€ and the cable RCA to XLR I’m using actually is just 10€ the pair.

Is not the correct one, only one wire inside and the shield, but sounds great so no reason to buy G Threes even if one has RCA outputs.
 
The two wire, one wire /shield thing has nothing to do with audible sound quality. It is just nicer to have a shield around the signal, which may lead to a better suppression of electomagnetic noise induced into the cable. With normal distances in a living room this should be no problem, except you are using your gear in a neon tube museum or Mr. Nicola Tesla's workshop.
 
The two wire, one wire /shield thing has nothing to do with audible sound quality.

Edit:
Admittedly not conclusive.
 
Another question, do impedance cause audible impact? RCA input has 10.000 ohms in my monitor, but XLR has 5.000 (has that something to do with the 2 parallel inputs or with the double voltage in balanced outputs?). Do a regular unbalanced signal feed twice the current to the circuit? Is better to match the impedance with some active or passive adapter like a DI Box?
No, you don't need to match impedances at all. Do you match the impedance of a p.amp (milliohms range) to that of a speaker (a few ohms or more)?
Of course, impedance matching does matter in high frequency applications, for two reasons: a) minimize standing waves, hence reflections b) maximize power transfer. Let's put it simply by stating that neither a or b apply in audio applications.
 
The two wire, one wire /shield thing has nothing to do with audible sound quality. It is just nicer to have a shield around the signal, which may lead to a better suppression of electomagnetic noise induced into the cable. With normal distances in a living room this should be no problem, except you are using your gear in a neon tube museum or Mr. Nicola Tesla's workshop.
This is correct wrt to the sound quality.

However, to clarify the shielding thing: It is advisable that the default setup requires to use a shield and two wires inside the shield (when the input is differential, i.e balanced, only the 2 internal wires can take advantage of the increased noise rejection). Both ends of the shield must be terminated. The connection of the internal wires depends on whether the driver side is single ended or balanced. The combination of end to end shielding and two wires inside, if properly connected, offers the best noise and radio interference rejection.

That said, the above does not mean that there aren't cases where a preamp and a power amp will work noise-free with lesser configurations. My dac is connected to the integrated anplifier via a simple rca to rca cable, for instance
 
Genelec recommends an XLR-RCA cable with XLR pin 2 -> RCA tip; XLR pin 3 -> RCA sleeve; XLR pin 1 (shield) -> RCA sleeve. Thus, the XLR’s pins 3 and 1 are tied at the RCA.
That's the only correct way to achieve best possible hum reduction... and most cables one can buy get this wrong.
Usually you have to make this cable yourself.
The off-the-shelf option is using a RCA-->XLR adapter at the source end (the RCA) and a normal XLR cable from there.
 
That's the only correct way to achieve best possible hum reduction... and most cables one can buy get this wrong.
Usually you have to make this cable yourself.
The off-the-shelf option is using a RCA-->XLR adapter at the source end (the RCA) and a normal XLR cable from there.
I’ve seen Neutrik ones, but I prefer cables because I don’t have a lot of space behind the streamer which is on a bookshelf.

I suppose by design that a proper wired RCA => XLR has half the signal to interference ratio than symmetric balanced signal, am I correct?
 
No, perfectly serious and one from their cheaper lines. This brand is absolute top class in selling snake oiled products at unbeliefable prices. The stupid, rich audiophiles love the brand. I would love to see one of their presentations, if there are really sonic differences, they must know some pretty dirty tricks. You don't need much fantasy to imagine what you can hide inside an audio cable.
 
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