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I want to send balanced audio from one room to another in my home. The audio will originate from a Soundcraft Spirit Folio 12/2 mixing console desk.

I'm assuming that the mix left/right and/or aux 1/2 outputs from this desk are balanced - but I'm not sure (so I've asked a seperate question above this here: What Soundcraft Spirit Folio 12/2 mixing desk/console outputs are balanced? ).

If they're not, I would connect them to a Behringer Ultra DI DI20 box and attach 2 balanced cables I have already laid to it. I have done some tests already that indicate that the signal sent is good quality with very low noise.

At the other end, I want to feed the audio input as RCA phono stereo pair into a Technics HiFi amplifier. For this:

I guess that converting balanced to unbalanced might be simple enough to implement in a cable. After all, the sound ultimately ends up that way by summing the +ve and -ve (mirror images of the sound), to cancel out the same noise signal by inverting one of the signals before summing.

Thanks for reading and any input appreciated.

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    "Pseudo-Balanced" I nearly fell off my chair laughing. That is marketing-speak gone mad. On the other hand, the Canford stuff looks good. Overall, that's a lot of money to be spending pushing a stereo signal round a house. How far are you pushing it? If it's less than 50m, I'd see how you get away with unbalanced right through. [50 is almost a bridge too far, but it may depend on how electrically noisy your environment is, 25 should be easy.]
    – Tetsujin
    Commented Aug 1, 2019 at 7:04
  • +1 thank you @Tetsujin The 25m cable is for connecting my home office (2nd bedroom) to my lounge/kitchen. Initially, I did use a 25m cable consisting of 2 unbalanced leads for left and right phono at each end. The result here was very noticable hum.
    – therobyouknow
    Commented Aug 1, 2019 at 19:08
  • I also already had 2 25m balanced XLR cables which I ran the same route. I plugged the audio source in my home office into a Behringer Ultra DI DI20 and connected the 2 balanced XLRs to it. At the other end, in my lounge, I plugged the cable XLR plugs into my Spirit Folio 12/2. Power for the Behringer Ultra DI DI20 provided by the Spirit Folio's phantom power. Then, unbalanced 6.35cm jacks with phono ends were used to connect the Spirit to my Technics amplifier. Result: very clean audio signal. Hum very faintly noticeable when Technics amplifier turned up to full volume and some hiss.
    – therobyouknow
    Commented Aug 1, 2019 at 19:12
  • Conclusion: the balanced cables making a huge difference. Their route includes running under my kitchen units (fridge/freezer, cooker, sink, dishwasher) as my flat's lounge is really a lounge/kitched combined room.
    – therobyouknow
    Commented Aug 1, 2019 at 19:13
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    As regards off-topic designation of this question by @Rory Alsop ♦, I can appreciate the thinking. However, although my problem is in a home setting, it does involve the application of professional technologies such as balanced XLR and products from professional audio product makers (Soundcraft and Behringer). Also, the setup in my home office is for a small home studio. Thank you for your considerations and time!
    – therobyouknow
    Commented Aug 1, 2019 at 19:19

2 Answers 2

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can I use cables that 'convert' balanced to unbalanced?

Yes, depending on your environment. As Mark said, the entire length of the cable is unbalanced, so you lose the noise rejection that a balanced link would give you. If you're not running power cables etc. near your audio lines you can get away with an unbalanced connection. I wouldn't rely on this in a setting where you regularly have to move your system (PA hire for example).

Can I assume that such cables are bidirectional in that if they are listed as unbalanced to balanced, they will also do it the other way around?

No. Those cables just make your link unbalanced in both directions.

The Canford converters you linked to, are bidirectional. They use a different method (a transformer) that actually converts the signal. This is basically a passive DI. If you place this converter at the end of a balanced link, you preserve the balanced link and its noise rejection.

As an alternative, an active DI would also work, but those have to be powered. They're usually built to take phantom power or a battery, I haven't seen DIs that can be mains-powered.

Note that in the same form factor as the Canford converter, you can also get converters that just connect pin 1 to 3 (as in the "pseudo-balanced" cable you linked to).

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  • +1 upvote and accepted answer for providing requested advice on the products in the question and for indicating a solution - the Canford converter. Thank you!
    – therobyouknow
    Commented Aug 1, 2019 at 19:14
  • On the basis of this answer and that it would appear that the Spirit Folio outputs I am using aren't balanced, then my perhaps final solution would be to have the Mix L+R or Aux 1/2 outputs (Which I assume to be unbalanced) going into a Behringer Ultra DI DI120 and the XLR cables coming out from that to go to the lounge. As the other end, in the lounge, I would use the Canford item to convert from balanced to unbalanced for the Technics amplifier, based on the Canford's technical spec that it is faithful to the balancing and doesn't lose it as you say.
    – therobyouknow
    Commented Aug 1, 2019 at 19:32
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    yes, good passive DIs can be expensive, and cheap ones degrade the signal.
    – Hobbes
    Commented Aug 2, 2019 at 7:26
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    The Canford item has another feature: unlike an active DI, it provides electrical isolation. This is useful if you have interference due to ground loops.
    – Hobbes
    Commented Aug 2, 2019 at 12:14
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    I've never used it. The specs are good enough that I'd be tempted to try one the next time I go shopping for DIs.
    – Hobbes
    Commented Aug 8, 2019 at 6:30
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Once you unbalance one end of an XLR cable (by linking pins 1 and 3) the entire length of the cable is unbalanced. You will need two devices at each end to send the signal balanced - a DI at one end and a balancing transformer or similar at the other end.

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  • +1 For advice related to that requested in the question, as well as to corroborate the answer given by @Hobbes. Thank you!
    – therobyouknow
    Commented Aug 1, 2019 at 19:15

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