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First, an assumption: given what I know about tip-sleeve and tip-ring-sleeve connections, using a TRS cable between two TS jacks just yields an unused contact/conductor in the cable.

Other than cost, all else being equal, is there any reason I should buy and use TS cables instead of TRS cables for various connections in my small studio?

6 Answers 6

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No, for a small studio, other than the cost difference, you can use TRS in the place of TS cables.

When you start looking at cable runs over around six meters (20 feet) you can start seeing some issues with resistance, depending on what you are using the wire for. The dual wire TRS cable will sometimes have a smaller gauge wire than the coaxial cable that is often used for TS.

Usually there is no significant difference though.

EDIT: thinking about it, there may be some slight durability difference in the two types of cables as well, if you are using the TRS cables in applications where they get flexed often, such as for a guitar cable. The tensile strength of the single wire is likely higher, resulting in a longer life before breakage in high flex use.

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  • I'm pretty sure, at extreme distances, there's also an element of reinforced interference in the 'spare' core, but I don't have the math to defend that speculation.
    – Tetsujin
    Feb 19, 2018 at 19:57
  • Having just ordered a good few trs plugs ( at good price) I wonder if it's worth shorting the r and s, for better conductivity.
    – Tim
    Feb 19, 2018 at 20:13
  • @Tim I have used two wire unified to tip in a TRS plug before, when I didn't have regular TS on hand. Feb 20, 2018 at 19:53
  • @Tetsujin Unless the spare core is somehow connected to your circuit, it should just be dead mass with no EM characteristics. I could be wrong about that, but I'm pretty sure you have to have poor insulation or a large amount of metal for reinforced interference to happen. Feb 20, 2018 at 19:58
  • For me, the tip is the tip. I'm more concerned about the point on the shaft which contacts the sleeve. If the ring is anywhere near, here may be problems.
    – Tim
    Feb 20, 2018 at 21:01
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One "typically TS application" that would definitely present an issue is the connection between a guitar with active electronics and an effects unit (stompbox).

The output of the guitar and the input of the stompbox almost always have a TRS jack that is used to power the device on:

One battery terminal (usually negative) is connected to the Ring terminal of the jack so that when a TS cable is inserted, it shorts the Ring and Sleeve terminals to connect the battery to the ground in the electronics.

Putting a TRS cable between two such devices connects their batteries together through the "floating" Ring conductor, with unpredictable results (and possible damage).

Using a TRS from an active guitar to a "universal" input (like on some audio interfaces) designed for either unbalanced TS or unbalanced TRS may apply battery power to the interface unit. It's probably blocked by a capacitor so as not to cause damage, but this is not guaranteed. The guitar electronics are not likely to power on.

Using a TRS cable between an active guitar to an amplifier or between a passive guitar and a stompbox may work, but is not guaranteed.

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  • This is absolutely true and I can confirm that a Boss RV-6 pedal won't work properly with a TRS cable!
    – JYelton
    Nov 2, 2021 at 20:16
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I wouldn't use a TRS cable in a TS socket because it's a tossup whether or not R makes contact or not. So you have a connection that will willy-nilly add a twisted core redundant core in parallel to the shield and not. This is quite unlikely not to result in handling noise.

In addition, a TS cable is coaxial and usually intended for high-gain high-impedance connections. A TRS cable (the twisted-pair variant for balanced connections, not a stereo cable) is not coaxial and intended for low-gain low-impedance connections. Not being coaxial means that it has quite higher parasitic capacities and inductivities than a straight coaxial cable which has a fixed geometry and dielectric between shield and core. This is important for high-impedance connections.

In contrast, a TS cable in a TRS socket is well-defined behavior and is often used for audio equipment that may accept balanced or unbalanced connections.

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  • This is very interesting. Exactly the kind of electrical concerns I was wondering about. Is it then accurate to say that the S contact point position in a given jack could sometimes be contacting the R on the plug, or even bridging R and S?
    – JYelton
    Feb 19, 2018 at 22:05
  • Could you translate the middle paragraph into words that make sense to the man in the street, please. I'm lost.
    – Tim
    Feb 20, 2018 at 8:06
  • I didn't get into it in my answer because there are too many variables in wire type used in the construction of the TRS cables. From what I've seen in audio cables, the shielded twisted pair wire is less common than parallel cladded wire. Seeing a detectable difference should only show up in long cable runs. Feb 20, 2018 at 19:49
  • Also, if the manufacturer of the connection parts are following industry specification, then the sleeve connector should not be connecting to the ring location. It would have to be a highly deviant input connector to do that. Feb 20, 2018 at 19:57
  • @Tim A coaxial cable means that one conductor is nestled within the other; think of the wire shielding on a cable with a center conductor (like "coax" cable you use for cable television) wrapped in a plastic or synthetic material (the dielectric). What user48234 is saying is that the cable construction has certain characteristics which may be better for applications that just use TS jacks.
    – JYelton
    Feb 22, 2018 at 4:03
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No major reason if wired correctly, i.e. keep the shield as ground and optionally either connect the other two wires together as the hot, or use one for hot and tie the other to the shield. You can cut one off, but might as well put it to use.

I have done both, my preference, mechanically, is if the wire has a good quality heavy shield I connect the other two to hot, if the shield is so-so I connect one wire to it and one to hot. Thin wire - both to hot. Not any really noticeable sound difference in the two methods.

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TRS cable may not work with active guitars, sometimes the additional pin causes short circuit.

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  • 2
    It's a valid point, but could you explain more how the short circuit occurs and what is its role in guitar with active electronics? Nov 2, 2021 at 20:31
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    Most guitars switches off the active circuit when no cable is plugged in to save battery. When you plug TRS jack into the plug, ring might cause a short circuit and prevent the activation of the circuit. I experienced this situation and here is a detailed explanation: talkbass.com/threads/… Nov 3, 2021 at 23:21
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Cutting all the nonsense - use TS for mono and TRS for balanced and appropriate cables - why? Because you don't know what the female socket on mono will touch - in ideal world, yes it should touch ground but in practice I had few cases that it was getting second leg of balanced signal (interface to amp as example). If you can't afford proper cables then I would say, try TRS and then TS - in 80%-90% cases it should be ok, if there is difference in signal use proper one.

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  • The stereo/mono distinction is different from the balanced/unbalanced though both can under some circumstances imply a change from 1 conductor + ground to 2 conductors + ground.
    – Theodore
    Apr 12, 2022 at 19:09

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