Not a great idea. Use a shielded twisted pair, like low noise mike cable. Shield to Pin 1, pair to pins 2 and 3.
http://www.hottconsultants.com/pdf_files/aes-2007.pdf
The page before is also important. There are no real benefits of doing it the way shown though really. Think about the complexity of connectors and wiring up, also more chance of creating inbalances between the cables.
Source: two PCM1702 per channel, one per phase, with dc coupled balanced IV stage, one per phase.
Load: a monolithic dual n-channel jfet per channel in the input stage of an inherently balanced amplifier for electrostatic transducers, also dc coupled.
Do you recommend balanced or single ended connections?
Considering physical pairing of - coaxial cables - or - twisted pairs with shield and soldered XLR connectors -, which would be more precise?
I currently use single ended ic's, because my load input stage only accepts RCA. I do not have measuring equipment, but I believe I have not been able to hear any ground loop or interference (or my brain found its rout to masking them or I do not have experience with more precise equipment to differentiate, I honestly do not know…).
But then I am not using the opposite phase of my source.
I was trying to achieve: 1 - lower capacitance; 2 - shield; 3 - crimped connections; and 4 - matched impedances of cables, connectors (50 or 75 Ohms for BNC, 110 Ohms for XLR's?), source and load (at least in the 20kHz region...). Thus I considered the option of low capacitance coaxial cable + BNC.
Now I see how twisting relates to EMI.
Does twisting have any impact in capacitance? Shall I be concerned with conductor to conductor capacitance in twisted pairs?
While I can't think of any good reason for using 2 coax's for a balanced interconnect, but if Henry W. Ott writes that it can be done, I'll take his word for it.
The main consideration about balance interconnects is symmetry and Shield Current Induced Noise (SCIN). Jim Brown has several papers (some with measurements) about mic cables & balanced interconnect cables. (near the bottom of the page)
Audio Systems Group, Inc. Publications
The main consideration about balance interconnects is symmetry and Shield Current Induced Noise (SCIN). Jim Brown has several papers (some with measurements) about mic cables & balanced interconnect cables. (near the bottom of the page)
Audio Systems Group, Inc. Publications
It is just one small example, if you read up on balanced connections (such as I posted above) they all recommend twisted pair as the best way.
The main advantage of twisted pair is isolation from ground noise, while the co-ax will work the shields of each co-ax has to be used for the return current for each signal, negating one of the advantages of balanced signals. Using co-ax will only work with differential signalling whereas using twisted pair as a BALANCED connection means you can transmit signals other than differential in balanced mode.
The main advantage of twisted pair is isolation from ground noise, while the co-ax will work the shields of each co-ax has to be used for the return current for each signal, negating one of the advantages of balanced signals. Using co-ax will only work with differential signalling whereas using twisted pair as a BALANCED connection means you can transmit signals other than differential in balanced mode.
The thing is that you get your immunity from noise via the application, build, etc, of the balanced 'idea', but the overall complexity in a home environment is generally not required, for line level. At line level, the extra hardware (active, connections, etc) are detrimental. None of that can be a perfect mirror,and they all disagree with one another in the micro domain and the micro transient domain within the context of in-situ complex signal function -so we get a serious problem in the micro detail. Obscuration, loss and false enhancement are all the order of the day. This is critical, as this vanishingly small signal distortion aspect is the very system by which the ear functions. The overall gross distortion can be lowered via measurement, but our ear does not use those aspects of engineering weighting, to hear. It uses the vanishingly small differentials in level and harmonic structure, to discern. That is how the ear works.
As we skip above the skin effect range and move up into complex high frequency harmonics in such a conductor arrangement, we find ourselves with insurmountable problems in complex waveform interference patterning, that is essentially chaotic and unpredictable. Resonances all over the place. The fact that we thought that we could go to balanced digital signal transfer as we went into higher sampling rates... and found out we could not..that is an explicit hint that balanced/twisted is a no-show in high resolution audio.
For micro level signals or any signal level, for that matter, I'd rather go for an overall shield and stay away from twisting with tight or close proximity conductors. All in an effort to send the signal across the balanced junction that has been presented by the component manufacturer, in as least damaged a way as possible. Hum is not a primary driving force in high resolution home audio and in a studio it should not be a problem either. It should be properly taken care of so it never rears it's head.
One should not allow the customer's illiteracy in these matters push one into producing something that is false. It's a huge problem, as the customer then turns to the company and people that produce the items that fit their perceptions... and then we have the continual promotion of illiteracy as being high art, the continual promotion of dogma that can only continue to worsen into more severe forms of inertia.. as it's premise is faulted and derailment is assured.. but never actualized. A train wreck that refuses to end. Human nature at play in the world of audio.
Basically, we need to get past this 'it's always been done this way' kind of inertia that emerged from the perception that studio work was 'the best thing to aspire to', this 'balanced dogma' that is in effect in home audio.
The key is understanding this rise of micro distortion, and then understanding that this is 'damaged goods' that we are perceiving as a form of quality increase. Never cease questioning, is the key point, even when you think the answer is in hand. Always leave the door open, otherwise you'll end up blocked and boxed in.
I've been playing with human perception of sound and micro distortions in all domains of audio, as a pair of bookends for at least 25 years, and that is what I've found hiding in the world of balanced signal transfer in the world of audio.
As we skip above the skin effect range and move up into complex high frequency harmonics in such a conductor arrangement, we find ourselves with insurmountable problems in complex waveform interference patterning, that is essentially chaotic and unpredictable. Resonances all over the place. The fact that we thought that we could go to balanced digital signal transfer as we went into higher sampling rates... and found out we could not..that is an explicit hint that balanced/twisted is a no-show in high resolution audio.
For micro level signals or any signal level, for that matter, I'd rather go for an overall shield and stay away from twisting with tight or close proximity conductors. All in an effort to send the signal across the balanced junction that has been presented by the component manufacturer, in as least damaged a way as possible. Hum is not a primary driving force in high resolution home audio and in a studio it should not be a problem either. It should be properly taken care of so it never rears it's head.
One should not allow the customer's illiteracy in these matters push one into producing something that is false. It's a huge problem, as the customer then turns to the company and people that produce the items that fit their perceptions... and then we have the continual promotion of illiteracy as being high art, the continual promotion of dogma that can only continue to worsen into more severe forms of inertia.. as it's premise is faulted and derailment is assured.. but never actualized. A train wreck that refuses to end. Human nature at play in the world of audio.
Basically, we need to get past this 'it's always been done this way' kind of inertia that emerged from the perception that studio work was 'the best thing to aspire to', this 'balanced dogma' that is in effect in home audio.
The key is understanding this rise of micro distortion, and then understanding that this is 'damaged goods' that we are perceiving as a form of quality increase. Never cease questioning, is the key point, even when you think the answer is in hand. Always leave the door open, otherwise you'll end up blocked and boxed in.
I've been playing with human perception of sound and micro distortions in all domains of audio, as a pair of bookends for at least 25 years, and that is what I've found hiding in the world of balanced signal transfer in the world of audio.
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Agreed, there are so many words in the English language and KBK likes to use most of them in his replies
To a true subjective Audiophile the content is as meaningless as the text in "The Art of Electronics" but certain words act a triggers reinforcing their beliefs (e.g. micro detail etc.) and proving they are correct in their super human hearing ability.
Balanced signal transmission and differential signalling does seem to be the in thing, most digital transmission is now LVDS, there has to be a reason (ah noise rejection and immunity)
To a true subjective Audiophile the content is as meaningless as the text in "The Art of Electronics" but certain words act a triggers reinforcing their beliefs (e.g. micro detail etc.) and proving they are correct in their super human hearing ability.
Balanced signal transmission and differential signalling does seem to be the in thing, most digital transmission is now LVDS, there has to be a reason (ah noise rejection and immunity)
Its the term generally used for digital differential signal transmission.
There is balanced interconnections (same impedance to ground for each leg, twisted pair cable, Differential routing on a PCB) and differential signalling (LVDS balanced audio).
Balanced interconnects can benefit both differential signals (equal and opposite signals in the two legs) and unbalanced signals where the voltages differ in each leg).
So there are two things at play here the balanced interconnection and balanced signals...
Clear as mud
There is balanced interconnections (same impedance to ground for each leg, twisted pair cable, Differential routing on a PCB) and differential signalling (LVDS balanced audio).
Balanced interconnects can benefit both differential signals (equal and opposite signals in the two legs) and unbalanced signals where the voltages differ in each leg).
So there are two things at play here the balanced interconnection and balanced signals...
Clear as mud
Agreed, there are so many words in the English language and KBK likes to use most of them in his replies
To a true subjective Audiophile the content is as meaningless as the text in "The Art of Electronics" but certain words act a triggers reinforcing their beliefs (e.g. micro detail etc.) and proving they are correct in their super human hearing ability.
Balanced signal transmission and differential signalling does seem to be the in thing, most digital transmission is now LVDS, there has to be a reason (ah noise rejection and immunity)
Those are single impedance, single frequency applications. The comparison is not even remotely applicable.
Perfection in broadband DC to high frequency as an all inclusive set, has far more demanding requirements. Requirements that cannot be met via LVDS transmission methodologies. You can make the bear dance via such transmission methods, but it just ... dances. It does not dance very well.
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