Crossing isn't much of an issue as long as the crossings are close to 90 degrees. What you want to avoid is running non-related cables next to each other.
OK, I connected how the manual says one should not do it.
But when connecting a single end source as described in manual we get a lot of hum/buzz. But no DC. At this time there is no chassie for the nCores so I can't do it exactly acc to manual but source ground to cold and + to hot. Nothing to "pin1".
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your...
layout is essentially perfect. I did the same with my stereo build: speaker binding posts at the outer edges, XLRs spaced in the middle, and IEC in the center. This layout allows one to get the most spacing internally of the AC wiring away from the input wires, and keeps speaker wiring away from input wiring as well. With a full width case this layout also allows one to take full advanatge of dual mono supplies and output modules, without having to go to the extra expense and complexity of building two mono blocks. I did not have extra speaker connections though, and I fitted my speaker binding posts in a verticle alignment so the cables (with spades) would run directly at a right angle away from the case-this avoids having the speaker cable having to make a sharp bend.
layout is essentially perfect. I did the same with my stereo build: speaker binding posts at the outer edges, XLRs spaced in the middle, and IEC in the center. This layout allows one to get the most spacing internally of the AC wiring away from the input wires, and keeps speaker wiring away from input wiring as well. With a full width case this layout also allows one to take full advanatge of dual mono supplies and output modules, without having to go to the extra expense and complexity of building two mono blocks. I did not have extra speaker connections though, and I fitted my speaker binding posts in a verticle alignment so the cables (with spades) would run directly at a right angle away from the case-this avoids having the speaker cable having to make a sharp bend.
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my experience XLR pin 1 needs to be connected to ground return of the source component, and the shield wire of the nCore module for there to be no hum.
If I had to connect a single ended source, I would wire the XLR jack as recommended by Hypex: Pin 1 to chassis, then shield wire from nCore module to chassis. Then I would make an RCA-XLR cable with sheild tied to pin 1 and RCA G, pin 2 to RCA hot, and pin 3 to RCA G.
You can test this without a chassis by attaching the sheild of the nCore module to pin 1 of your XLR jack, I think you will have silence if that sheild wire connects to your source G.
Also, have you confirmed that your source has <50 mV DC, make sure, as the nCore is DC coupled and cannot have significant DC on its input.
OK, I connected how the manual says one should not do it.
But when connecting a single end source as described in manual we get a lot of hum/buzz. But no DC. At this time there is no chassie for the nCores so I can't do it exactly acc to manual but source ground to cold and + to hot. Nothing to "pin1".
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my experience XLR pin 1 needs to be connected to ground return of the source component, and the shield wire of the nCore module for there to be no hum.
If I had to connect a single ended source, I would wire the XLR jack as recommended by Hypex: Pin 1 to chassis, then shield wire from nCore module to chassis. Then I would make an RCA-XLR cable with sheild tied to pin 1 and RCA G, pin 2 to RCA hot, and pin 3 to RCA G.
You can test this without a chassis by attaching the sheild of the nCore module to pin 1 of your XLR jack, I think you will have silence if that sheild wire connects to your source G.
Also, have you confirmed that your source has <50 mV DC, make sure, as the nCore is DC coupled and cannot have significant DC on its input.
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I wasn't actually complaining, I was just pointing out that we seem to agree about the solution
By "input end of...input cable" do you refer to load or source component? Respectfully, the term "input" might be ambiguous because both ends of an IC "input" to its respective connector. Conversely, the terms "load" and "source" are explicit and defined more consistently.
Ideal IC for unbalanced source is as follows: Tie XLR pin 3 (inverted audio signal) to RCA ground/shield; the closer this tie occurs to the source/RCA plug the better/quieter is performance.
You are right. My terminology was confusing.
I tried to avoid talking about XLR connector pins, because I am not sure TNT is using XLR connectors at all. Sounds like his amp is intended for unbalanced sources and has RCA inputs.
In any case, to be clear - the inverting input and the shield of the nc400 input cable should both be connected to the ground of the input at the point where unbalanced becomes balanced.
So you don't have anything to drain earth currents?
Pin 1 needs to go somewhere or you've lost the reason why balanced (xlr) gives benefits
Connect it to the screen on the nCore input cable
Which in turn connects to ground at the amp
If you look at the data sheet you can see this is what is recommended, except that the diagrams assume the case is conductive. So with a conductive case the connection between pin 1 and the screen of the input cable is via the case
Pin 1 needs to go somewhere or you've lost the reason why balanced (xlr) gives benefits
Connect it to the screen on the nCore input cable
Which in turn connects to ground at the amp
If you look at the data sheet you can see this is what is recommended, except that the diagrams assume the case is conductive. So with a conductive case the connection between pin 1 and the screen of the input cable is via the case
OK I need probably to spill it all. My pin 1 in the XLR input connector is connected to the earth and the ampon in the input connector of the nCore. This gave actually 1,7-2,4 V DC on the output when pin 1 was connected to Cold. (pin 1 to Cold gave the DC with or without the preamp connected).
With my balanced trafo out DAC this is no problem as threes no short between any pins of cource.
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With my balanced trafo out DAC this is no problem as threes no short between any pins of cource.
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Attachments
The XLR Pin 1 in a balanced analog audio interconnect is a shield not a ground. This shield is always connected to the chassis at the send end, but it is sometimes not connected at the receive end. Other times a hybrid connection is made at the receive end using a series capacitor (or anR/C network).
My nCores has XLR
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Tie XLR pin 1 to XLR shield/frame (all or most XLR have four terminals, one of which is XLR shield; there's no reason not to shield both the XLR plug and jack themselves regardless whether or not amp chassis is conductive).
Following the above instructions, for conductive chassis, unless paint or anodize prevents it, XLR pin 1 carries source shield to XLR frame then to the entire chassis, either via direct contact jack-to-chassis, fasteners, or both.
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Please forgive me for this correction, meant only to promote the use of common audio terms which are easily identified and seldom confused: "load" and "source."
For NC400, Hypex tech instruction was to tie XLR pin 1 to shield of XLR jack. IOW this is sole correct wiring instruction, not optional, though other components may wire differently as you state.
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OK, just to be clear - you have the shield of the nc400 audio input cable (and the nampon input lead) connected to the XLR pin 1, with non-inverting input to pin 2 and inverting input to pin 3, right?
So how is your source connected? With a RCA-to-XLR cable? Or some XLR cable you have made yourself? How is it wired?
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