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1/4 to rca? possible?
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| envisione |
| can RCA act as balanced inputs? for example a mixer with 1/4 outs and a soundcard with rca ins? can it still work? |
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| No Left Turn |
| Yes, you'll be able to go from the mixer's outputs into the soundcard's inputs. However, RCA is an unbalanced connection and you won't have a completely balanced signal. |
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| T-Soma |
| Any cable you want can be balanced but I cant say i have seen many soundcards with RCA balanced. For a balanced RCA Stereo signals I think you would need 4 cables. Iv seen it done at a radio studio I go to sometimes. In your situation I doubt it is going to work because it is probably just regular RCA. Iv fairly sure of all this but im sure someone will come along and either confirm this or destroy it... either way, I hope my post has helped. |
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| Pjotr G |
| yeah, balanced audio needs 2 channels for mono signal, so you can't get balanced stereo with 2 rca cables. |
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| sr126 |
| quote: | Originally posted by T-Soma
Any cable you want can be balanced but I cant say i have seen many soundcards with RCA balanced. For a balanced RCA Stereo signals I think you would need 4 cables. Iv seen it done at a radio studio I go to sometimes. In your situation I doubt it is going to work because it is probably just regular RCA. Iv fairly sure of all this but im sure someone will come along and either confirm this or destroy it... either way, I hope my post has helped. |
i have never seen what they have at the radio station, but from what i know, rca = unbalanced. the rca plug only has 2 contact points -hot, and ground. also 75ohm rca cable only has one strand to carry the signal (hot).
a balanced cable requires a plug that has three contact points, hot, cold, and ground. take mic cable, inside the cable there are 2 or 4 strands inside that will carry the hot, and cold signal.
even if you terminate mic cable w/an rca plug, you can only mate one strand to the pin of the rca plug. -the end result will be same as using rca cable.
you can use an adapter to go from a balanced out into an rca in, but you loose the benefits of having a balanced connection.
if you just want to get the job done, try to keep the connection between the mixer and computer as short as possible, assuming that you card isn't adding all kinds of noise of it's own.
if you want something pimpy-ier, then you definately need to upgrade your card. i don't think there's anything @the semi-pro level that does not offer at least one kind of balanced connection. you will always get atleast a set/pair of 1/4" combo TS/TRS jacks, or a pair XLR, or probably both.
if you're having trouble visualizing the whole strand/2 or contact thing, visit a music store and grab a microphone cable (balanced, xlr) and grab a guitar cable or instrument cable (unbalanced, TS) and grab the end/pin of each cable, and un-screw the body of the connecter, and pull them apart. you will see the mic cable will have two little strands inside the cable. each strand is soldered to it's own pin on the xlr connector, while the shielding is soldered to the third pin.
this demonstrates what pjotr g said about a balanced cable needs two channels to carry a mono signal.
on the guitar/instrument cable you will see only one strand, and that one is soldered to the pin in the middle of the plug, while the shielding is soldered to long part of the plug near the part of the plug that clamps onto the cable to ground the connection.
also you will notice that w/guitar/instrument cables that the on the tip, you will see that there is only one ring. on a 1/4" TRS cable, the tip will have 2 rings. -like the tip of connector on your headphones.
one ring = TS (tip/sleeve) = unbalanced. two rings = TRS (tip/RING/sleeve) = balanced.
if you grab cables that have molded plugs, like the cheap-y rca cables that come w/home audio equip... you will not be able to remove the plugs to inspect the insides. make sure you grabe the cables that have metal plugs.
i know i just did a lot of talking, but i hope all the extra info helps in picking the right cables the first time around for your application and avoid some headaches... especially w/dealing w/ 1/4" cables, because they look the same, except for the number of rings on the tip of the connector. |
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| Derivative |
| quote: | Originally posted by T-Soma
Any cable you want can be balanced but I cant say i have seen many soundcards with RCA balanced. |
a single RCA cable can never be balanced. Why? It is terminated in only 2 places - the tip and sleave. If you were to cut open a quarter inch TRS (Tip Ring Sleave) cable you will notice there are 3 signal carrying lines (positive, negative and ground) and each end is terminated in 3 places, with the ground connected to the sleave, the positive line to the tip and the negative line to the ring.
an RCA cable doesnt have any point at which to connect the negative line for electronic balancing. And even if you engineered one, it still wouldn't work in a balanced system because there is no RCA phone line input that can accept the antiphase signal, not least perform the reverse polarity trick in order for the balancing to work.
If you terminate one end of a balanced TRS line with an RCA phone connection, you end up with an unbalanced line. This is because you have connect the negative line and the ground to the sleave of the RCA connection, leaving you with only the positive line and the ground.
I guess you could use 2 separate cables and 2 separate inputs then perform the antiphase trick after conversion. Sum the result to a singal mono channel and output it back into a separate input. But really whats the point? Not to mention the fact you would be doubling the number of conversion stages which will sound . Maybe you can do it without feeding the ouput back into the input. Im not entirely sure how it would work. I just dont know - never tried because I have never been in a situation where I absolutely had to try and balance a system that was not in anyway designed to be balanced. |
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