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[Josh Demolar]

Ok, first off let me say what I’m not asking. I already know that a balanced cable does nothing unless it is carrying a balanced signal, and guitars and amps only send/receive unbalanced signals.

What I AM wondering is why my church might have balanced cables running from the stage to the amp isolation boxes but only TS connectors. The cables are probably between 50-100 feet long. I don’t notice any capacitance issues (I don’t think that can be solved anyway without converting the signal to balanced), but I also have a buffered output from my pedalboard so maybe I just don’t notice signal loss even though it may occur for others. And I don’t know if it helps reduce noise/interference. But we need to repair/replace the cable because of bad connectors and don’t want to mess anything up.

The one who put the system together unfortunately passed away several years ago, so I can’t go to the source. But based on the rest of the system, he and the company he hired to design and implement our audio system knew what they were doing.

Is there some trick I don’t know about where combining one of the two signal cables either to the other on or to ground (maybe at one or both ends) solves some kind of problem? I’ve searched the internet with every variation of the question I can think of and I get nothing.

[Patrick Tracy]

FYI, we use our real names here. A mod will soon lock this thread until you update yours. But once that's all sorted I'm sure you'll get good answers to your questions.

[Nathan Eide]

You are right that it seems odd to have unbalanced signals. And you are also right about the general needs for balanced signals.

What are these lines connected to?  And what type of connection (physical & electrical) is on the other end?  Is it a balanced connection?  Is it going into a mixer and if so what type of input, a line or mic input?

Electrically, there are two main issues with unbalanced into balanced lines: noise rejection and impedance matching. Balanced lines are better for not picking up EMI noise with common mode rejection. (Look it up.)

Unbalanced signals are generally high impedance (sometimes called Hi-Z), and most balanced are low impedance (Lo-Z). High impedance connections degrade quickly over distance, which is why some people recommend not using guitar cables over 15 feet long.

If you are connecting to a low impedance balanced input, such as a mixer mic input, the common answer is a direct box (also called a DI box).  A direct box contains a transformer or electronics to convert the unbalanced, high impedance signal to balanced low impedance, usually on an XLR connector.  This is the most common way to connect an instrument on stage to a mixer mic input.  Connect the unbalanced instrument output (guitar, bass, keyboard) with a short cable to a direct box.  The balanced output can then go hundreds of feet to the mixer or other preamp input.

One more note on direct boxes. There are two general types, passive and active.  Passive DI boxes use a transformer to convert to balanced lo-z.  Active DI’s use electronics and require power.  Usually this means 48 volt phantom power, but some models can use a battery or other power supply.  If you have a mixer with phantom power, you can use either type.  If not, you will need a passive or self powered type.

HTH,
Nathan

[Josh Demolar]

You are right that it seems odd to have unbalanced signals. And you are also right about the general needs for balanced signals.

What are these lines connected to?  And what type of connection (physical & electrical) is on the other end?  Is it a balanced connection?  Is it going into a mixer and if so what type of input, a line or mic input?

Sorry it wasn’t that clear in my original post. These are two cables, each running from stage (meant for guitar/pedalboard out) to guitar amps in the iso booth. So basically Guitar -> Amp, which is why the balanced line doesn’t make sense. If a pro shop hadn’t made these, I would think it was a classic case of someone who knew something about balanced cables but not enough to know it also needs the signal converted to a balanced one. There are no DIs or other devices in the path on these lines. Just the cables themselves.

I realize I can put a DI on these lines to convert to balanced, though they would need to be re-converted back to unbalanced at the other end to go into the amps. But why the fuss with balanced cable in the first place? What would combining the two “hot” inner wires do? What would leaving one inner wire disconnected at one end do? What would sending one of the inner wires to ground do? One of these things is happening, I just can’t figure out why as I don’t see any of these possibilities recommended anywhere, even as a hack.

[Jonathan Kok]

The wire used does not determine whether a line is balanced or not. How it is terminated, and what it is terminated to, is what determines whether it's balanced or not. You say you have 'balanced' wire; by this I assume you mean 2-conductor shielded w/ drain wire? However, it's terminated to a TS connector, with both conductors tied to the tip. This makes it unbalanced, NOT balanced.

Why this wire? If their shop is like mine, it's the only cable they carry. We don't stock 'unbalanced' wire. And I certainly wouldn't order in special cable just for this. On top of that, the cable could be adapted in the future for balanced use with a simple change of connector.

HTH!

[Matthias McCready]

These are two cables, each running from stage (meant for guitar/pedalboard out) to guitar amps in the iso booth. So basically Guitar -> Amp, which is why the balanced line doesn’t make sense. If a pro shop hadn’t made these, I would think it was a classic case of someone who knew something about balanced cables but not enough to know it also needs the signal converted to a balanced one. There are no DIs or other devices in the path on these lines. Just the cables themselves.

Josh, the product you are looking for is the Radial SGI. 

[Scott Hofmann]

Sorry it wasn’t that clear in my original post. These are two cables, each running from stage (meant for guitar/pedalboard out) to guitar amps in the iso booth. So basically Guitar -> Amp, which is why the balanced line doesn’t make sense. If a pro shop hadn’t made these, I would think it was a classic case of someone who knew something about balanced cables but not enough to know it also needs the signal converted to a balanced one. There are no DIs or other devices in the path on these lines. Just the cables themselves.

I realize I can put a DI on these lines to convert to balanced, though they would need to be re-converted back to unbalanced at the other end to go into the amps. But why the fuss with balanced cable in the first place? What would combining the two “hot” inner wires do? What would leaving one inner wire disconnected at one end do? What would sending one of the inner wires to ground do? One of these things is happening, I just can’t figure out why as I don’t see any of these possibilities recommended anywhere, even as a hack.

I am mystified by the way you are phrasing your questions about the cable:  "What would combining the two “hot” inner wires do? What would leaving one inner wire disconnected at one end do? What would sending one of the inner wires to ground do? One of these things is happening,,,,,".
If you KNOW it is a cable with two conductors and a shield, you either saw the information printed on the outside of the cable or unscrewed the handle of the TS phone plug on one or both ends. If you have access to each end (eg the plugs are not molded on) then you already know how they are connected and should just state that.
If you said, for example, the two conductors are both attached to the tip of the phone plug at each end and the shield is attached to the sleeve at each end, folks would
be able to explain why a lot easier!!

[John Roberts {JR}]

You can't use a 50' guitar cable without affecting the guitar pickup sound (cable capacitance).

A DI buffer before the long send seems like the logical remedy.

You may need to experiment with interfacing with the amp.

JR

[Steve-White]

They may have lifted the shield at the stage or instrument end and carried the chassis or (-) through, as there is no actual electrical "ground" in the signal path of these systems.

[Josh Demolar]

Josh, the product you are looking for is the Radial SGI. 

I'm aware of the SGI, and am considering purchasing (or two sets actually, for two guitar lines to two amps) if necessary. Still trying to figure out why we haven't needed it yet for the past several years.

[Josh Demolar]

I am mystified by the way you are phrasing your questions about the cable:  "What would combining the two “hot” inner wires do? What would leaving one inner wire disconnected at one end do? What would sending one of the inner wires to ground do? One of these things is happening,,,,,".
If you KNOW it is a cable with two conductors and a shield, you either saw the information printed on the outside of the cable or unscrewed the handle of the TS phone plug on one or both ends. If you have access to each end (eg the plugs are not molded on) then you already know how they are connected and should just state that.
If you said, for example, the two conductors are both attached to the tip of the phone plug at each end and the shield is attached to the sleeve at each end, folks would
be able to explain why a lot easier!!

I did open one end, but it was a couple months ago. I don't have visible access to it at the time to verify what the inside configuration is. Hence the questions in multiple possibilities. But if none of those possibilities trigger a thought of "Oh yeah, doing _____ with a balanced cable with TS connectors solves ________ problem," then either there isn't a reason for the cables being wired this way, or you just don't know. Either way, since my specific questions are about as helpful as what I've researched online, I think I've got my answer. Thank you for your response and apologies I didn't have the details confirmed.

[Josh Demolar]

The wire used does not determine whether a line is balanced or not. How it is terminated, and what it is terminated to, is what determines whether it's balanced or not. You say you have 'balanced' wire; by this I assume you mean 2-conductor shielded w/ drain wire? However, it's terminated to a TS connector, with both conductors tied to the tip. This makes it unbalanced, NOT balanced.

Why this wire? If their shop is like mine, it's the only cable they carry. We don't stock 'unbalanced' wire. And I certainly wouldn't order in special cable just for this. On top of that, the cable could be adapted in the future for balanced use with a simple change of connector.

HTH!

Thank you, this is very helpful. I didn't think that there would be any reason to use 2-conductor wire (apologies for using the wrong term, as I stated in my original question, I do know that it's not balanced unless the signal sent and received by the devices on each end is balanced). But if using 2-conductor wire is useful because it's just more flexible for multiple uses, then I can stop guessing what kind of trickery they were trying to pull.

[Steve-White]

The possibility of the contractor "using what they had" makes a lot of sense in terms of wire type.

[Caleb Dueck]

I'm aware of the SGI, and am considering purchasing (or two sets actually, for two guitar lines to two amps) if necessary. Still trying to figure out why we haven't needed it yet for the past several years.

Another vote for SGI boxes.  Just because you're getting signal that isn't mostly radio doesn't mean it's not being degraded.  They aren't even expensive, and will show you how much loss/degradation you're dealing with.  Plus, I'd rather know the signal is good, rather than hope it's 'good enough', and hope something bad doesn't happen early on a Sunday morning. 

[Brian Jojade]

Thank you, this is very helpful. I didn't think that there would be any reason to use 2-conductor wire (apologies for using the wrong term, as I stated in my original question, I do know that it's not balanced unless the signal sent and received by the devices on each end is balanced). But if using 2-conductor wire is useful because it's just more flexible for multiple uses, then I can stop guessing what kind of trickery they were trying to pull.

This is most likely the case. The cost difference between 2 conductor wire vs single conductor wire for install is minimal. There is very little use for long single conductor wires, so most likely that would have been special order and cost more. Instead, pull what you have and terminate as needed.

It does sound though that the install is ‘wrong’ based on general practices, but if it works, who cares?

[Andrew Broughton]

Another application of 3-wire cables used with unbalanced guitar signals is the Fractal "Humbuster" system. It actually works, but only if the device supports it. (i.e. their modellers)
https://wiki.fractalaudio.com/wiki/index.php?title=Humbuster

[ProSoundWeb Community]