The cable that grounds the chassis together is not the same as a balanced cable.
A balanced cable is related to balanced circuit design.
A balanced cable is related to balanced circuit design.
Anyone else making their own cables?
Over the years I have owned a lot of different brands of very sought after and very expensive cables(interconnections both balanced and single ended and speaker cables). Each time selling and then trying another. I recently have been experimenting with making my own. I have been doing a lot of reading on the subject of design. Also I have been dissecting some old inexpensive ones I had lying around. I am starting with ic's. From my experience and what I have read, when done right balanced is the superior method. What I had not realized is that single ended cables can be balanced as well. In fact Annolog(vinyl) starts out as balanced. This is the way I have chosen to make my cables. Also I have found that grounding at the receiving end and simply connecting the grounds at the sending side works best and in my view is the only real reason for directional cables. I have been using wbt and eichmann ends. I would like to hear from others with knowledge of design, cable types and materials, soldering, end type(brands) and their benefits and covers to improve final appearance. I would also be interested in any other point I have not mentioned or to simply disagree with any assertion I or anyone else makes on this subject. I do realize that cables are the single most controversial subject in this hobby. I am not trying to settle that argument. Just offer another option. It may even prove cheaper to buy a brand cable then make your own. I do not have a degree in engerneering nor am I an electrician or computer genius. Just a long time audiophile. My single ended cables are for vinyl set up(turntable to step up transformer to phono stage). Balanced everywhere else. My system is fully balanced(as earlier described) from end to end. Thanks for informative insights.
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01-26-15: PkoegzHere's my take: Single-ended by definition means the same thing as unbalanced. So a single-ended cable or connection cannot be balanced. It is possible for a balanced connection to be implemented via RCA connectors, but that is not usually done. A balanced cable will have two symmetrical conductors, which are often twisted together and are often surrounded by a shield. A balanced connection, which can also be referred to as a balanced interconnection or a balanced interface, will utilize a balanced cable, and the interface circuits in the connected components will utilize the cable in a manner such that the two conductors have the same impedance between each conductor and ground. A balanced connection will often, although not always, convey signals on the two conductors that are of essentially the same amplitude but have opposite polarities. On the other hand, if one conductor is provided with a signal and the other is provided with zero volts (i.e., ground), that still constitutes a balanced connection, as long as the two conductors are symmetrical and have equal impedances to ground. A balanced cable terminated with XLR connectors will have a signal conductor connected between pin 2 of the two connectors, and the other signal conductor connected between pin 3 of the two connectors. The shield will be connected between pin 1 of the the two connectors, and occasionally also to the housing of the connectors. Some manufacturers use the same wire type for their XLR and RCA cables. In those cases, if RCA connectors are used one conductor will connect the RCA center pins together, and the other conductor will connect the RCA shells/sleeves together. The shield will usually be connected to the RCA shell at just one end. That end should preferably be connected to the component which drives the cable, as Pkoegz indicated (although I think he inadvertently left out the word "not" when he said "I have found that [NOT] grounding at the receiving end and simply connecting the grounds at the sending side works best and in my view is the only real reason for directional cables"). RCA jacks are available in forms which may or may not isolate the shell from the chassis of the component they are mounted on. Well designed modern components usually utilize isolated jacks. Components utilizing XLR connectors should ideally connect pin 1 to chassis, but in many cases connect it to circuit ground/signal ground instead, resulting in increased susceptibility to ground loop issues or other adverse consequences. See this paper. Regards, -- Al |
Since I am so ignorant of the technical details of electrical or electronics that I still don't understand the difference between chassis ground, circuit ground, and signal ground, I am very hesitant to suggest that Al may not be 100% correct. However, fools rush in, so please take this with a grain of salt... While there may be a pro audio standard for how XLR plugs and jacks are wired, I believe that there is no absolute standard in consumer audio equipment. Some audio gear uses a different pin out/in. I had an Electrocompaniet EMC-1 CDP that was wired differently and so I had to have custom-wired XLR cables made up. Also, remember that some equipment has XLR jacks and/or plugs, but the circuits they tie to are not true balanced circuits. In that case, the jacks or plugs function as adapters. I hope that Al (Hi, guy, get much snow?) or someone else will correct me if I am wrong. |
Hi Michael (Swampwalker), I don't see any inconsistency between our two posts. Regarding the EMC-1 you had, equipment that is made in some European and Asian countries sometimes applies the non-inverted signal in the balanced signal pair to XLR pin 3, and the inverted signal to pin 2, rather than the opposite which is the usual convention in the USA and many other countries. In those cases, to maintain correct polarity/absolute phase, if one considers that to be audibly significant (and if one is using multiple sources, so that absolute phase cannot be restored by swapping + and - at the amplifier outputs or the speaker terminals), the cable would have to connect pin 2 at one end to pin 3 at the other end, and vice versa. I suspect that is what you are referring to. If not, and if pin 1 were used for a signal connection, that would have been really oddball, and incompatible with conventionally designed cables and components. Re your last question, fortunately and surprisingly Snowmaggedon didn't materialize down here. Only about 8 inches so far. Seems like the storm moved further east than expected, and eastern MA and southeastern NH are having the worst of it. Best, -- Al |
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