Balanced or unbalanced jacks on units where it doesn't specify

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famous beagle

famous beagle

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I have a few older units in my rack and can't find info in the manuals about whether or not the 1/4" connections are balanced or unbalanced. I was hoping I could find an easy way to tell without having to open them up (I'd have to take them out of the rack), and I saw this on a forum:
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"One way to verify an unbalanced jack is: put a TRS cable into it. Use multi-meter to check continuity between R and S on the end of the cable.
If there is continuity, it is unbalanced for sure. (if there is not continuity, that does not necessarily prove its balanced, however)"
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My question is this: Why would you have continuity between the ring and sleeve? I have a guitar output (TS) jack lying around in my bag of parts, and when I plug a TRS cable into it, nothing is making contact with the ring at all. Only the sleeve and tip are making contact with anything.
When I test for continuity between ring and sleeve, I (as expected) do not get it.
Am I missing something?

The post on the forum was from 2009, so I can't ask the poster for clarification. But I don't see how that would work. :confused:
 
If a socket is unbalanced then the unit expects a jack where there are only two circuits, the tip and the sleeve, the ring and sleeve at one piece of metal, so popping in a 3 circuit plug with the tags touchable means sleeve to tip is some resistance measurement, or open, but the ring and sleeve position will be connected. If you also stuff a jack into an input that is active and volume up, tapping the tip connector makes an audible buzz, if the ring tag also buzzes, it’s balanced. Tapping the sleeve is silence, or often, if there is already a tiny buzz, it makes it quieter.
 
If a socket is unbalanced then the unit expects a jack where there are only two circuits, the tip and the sleeve, the ring and sleeve at one piece of metal, so popping in a 3 circuit plug with the tags touchable means sleeve to tip is some resistance measurement, or open, but the ring and sleeve position will be connected. If you also stuff a jack into an input that is active and volume up, tapping the tip connector makes an audible buzz, if the ring tag also buzzes, it’s balanced. Tapping the sleeve is silence, or often, if there is already a tiny buzz, it makes it quieter.

Thanks for the response. I'm a little confused still. First of all, not to be picky, but when you said this:

the ring and sleeve at one piece of metal

Did you mean to say "are one piece of metal?" (I'm not trying to be difficult, but I just want to understand.) If so, I don't know what you mean. They're separated by a band, right? There's no continuity between the sleeve and ring when you check on the cable itself. So how can there be continuity between them unless something is bridging them? As you can see in this picture (forgot to include it in my original post - maybe it'll help shed some light on my confusion), nothing is contacting the ring at all. So how can there be continuity?

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Balanced 1/4" connections/sockets should have two "click" points, one as the tip locks into the 'ring' contact (the first click) then a second click as the tip pushes past the ring and locks into the actual tip contact. If it is not either an insert or a stereo out/in socket then it 'should' likely be a balanced connection.

I honestly don't get the continuity thing either. Unless a particular TS socket's 'tip' contact is constructed in such a wau to contact both tip and ring?
 
Balanced 1/4" connections/sockets should have two "click" points, one as the tip locks into the 'ring' contact (the first click) then a second click as the tip pushes past the ring and locks into the actual tip contact. If it is not either an insert or a stereo out/in socket then it 'should' likely be a balanced connection.

I honestly don't get the continuity thing either. Unless a particular TS socket's 'tip' contact is constructed in such a wau to contact both tip and ring?
Thanks for the tip. I've tried the "number of clicks" thing before, and it doesn't seem terribly reliable to me. When testing the idea, I plugged TRS cables into known (properly working) balanced 1/4" jacks, and sometimes the two "clicks" are easily discernible, and other times pretty much only one is detectable. In another instances, I plugged a TRS cable into the input on my Fishman Loudbox Mini acoustic amp, and it feels like two clear, separate clicks, although the diagram in the manual clearly shows a TS jack.

I'm guessing it has to do with the tension of the jack's contact maybe.

Regarding your last sentence, I thought of that, but that would mean continuity between the ring and the tip, not the ring and the sleeve, which is what the post said. I should mention that several other people chimed in and agreed with the poster's statement on that forum.

Clearly, I'm not understanding something, or I'm performing my experiment incorrectly or something, because when I check continuity between ring and sleeve in my picture above, there is none.
 
Sorry for the confusion. The typo/autocorrect made it worse. If, like me, you have some cables with 3 circuit, TRS connectors, you need to remember that some devices like guitars - have jack socket contacts that connect ONLY to tip and the sleeve - the ring contact has nothing touching this. Other devices - and it's common in synths, for example, if they are unbalanced, then the sleeve and ring are connected, as in a guitar jack - where they are connected by the long sleeve and no ring.

Think about a balanced patch bay - one of those that has sockets on the front for patching, but has 3 circuit jacks on the rear. When unbalanced jacks are used at the rear to connect to unbalanced kit, the 3 circuits in the jack socket are converted, by that jack shorting ring and sleeve, to unbalanced - even though they are balanced (capable) connectors. Any unbalanced source automatically unbalances the destination.

In real terms it doesn't really matter. A test meter across ring and sleeve reveals unbalanced as a short.
 
Sorry for the confusion. The typo/autocorrect made it worse. If, like me, you have some cables with 3 circuit, TRS connectors, you need to remember that some devices like guitars - have jack socket contacts that connect ONLY to tip and the sleeve - the ring contact has nothing touching this. Other devices - and it's common in synths, for example, if they are unbalanced, then the sleeve and ring are connected, as in a guitar jack - where they are connected by the long sleeve and no ring.

Think about a balanced patch bay - one of those that has sockets on the front for patching, but has 3 circuit jacks on the rear. When unbalanced jacks are used at the rear to connect to unbalanced kit, the 3 circuits in the jack socket are converted, by that jack shorting ring and sleeve, to unbalanced - even though they are balanced (capable) connectors. Any unbalanced source automatically unbalances the destination.

In real terms it doesn't really matter. A test meter across ring and sleeve reveals unbalanced as a short.
Thanks for the clarification. I was wondering about that - the fact that different types of jacks may be used on guitars than other pieces of equipment - but the guitar jack was the only thing I had lying around at the time (without having to open something up).
 
yes I asked the same question in DIY thread a long time ago because my interface LINE IN is Unbalanced per the Manual (and meter testing confirmed)...
..but the mfg used Balanced 1/4 plugs! but then soldered the sleeve and ring together internally making it unbalanced.
 
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