Thanks. But does this "matching" work for combinig two NCore NC400 to one SMPS1200 ? Looks to me, as if it is just hooking up one NCore NC400 and not two, doesn't it ? Employing two NCores should probably need some (logical ?) "interleaving" done, because they might carry opposing signal values in a worst case situation.
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No, they should be simply connected in parallel, unless you are trying to do bridging. The worst case is not opposing signal values, but peak output on both amps at the same time, and there is not much you can do about that.
No, no bridging just ordinary 2-channel usage.
I had to choose this layout using just one power supply, because i lack the space inside the cabinet for adding another power supply. And the cabinet can't be any larger because there is only limited space left inside the (open) sideboard. The mono amp (NCore) for driving the center channel has to sit ontop of it already due to this. Both cabinets feature holes in bottom and top plates for thermal "management". The one on top has to "live"
with the increased air temperature escaping from the top of the amp underneath...
Why would the combined peak power output be a problem ?
The SMPS1200A400 should have enough current reserve - from the datasheet at least - to supply it to both units at the same time, doesn't it ?
At 230VAC and a 4 Ohm load (1%THD/1kHz) it states 3x 340 Watt (typical) and 3x 400 Watt (max), 8 Ohm load (1% THD/1kHz) it states 3x 200 Watt (typical) and 3x 230 Watt (max). Am i missing something here ?
What about those control signals like "nFATA" if they have opposing status ? They are open collectors, i know ...
I had to choose this layout using just one power supply, because i lack the space inside the cabinet for adding another power supply. And the cabinet can't be any larger because there is only limited space left inside the (open) sideboard. The mono amp (NCore) for driving the center channel has to sit ontop of it already due to this. Both cabinets feature holes in bottom and top plates for thermal "management". The one on top has to "live"
with the increased air temperature escaping from the top of the amp underneath... Why would the combined peak power output be a problem ?
The SMPS1200A400 should have enough current reserve - from the datasheet at least - to supply it to both units at the same time, doesn't it ?
At 230VAC and a 4 Ohm load (1%THD/1kHz) it states 3x 340 Watt (typical) and 3x 400 Watt (max), 8 Ohm load (1% THD/1kHz) it states 3x 200 Watt (typical) and 3x 230 Watt (max). Am i missing something here ?
What about those control signals like "nFATA" if they have opposing status ? They are open collectors, i know ...
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On the NC400 the DC error output is indeed an open collector output. You can just tie them together. If either of the NC400 goes into an error, the SMPS should shut down.
It isn't really a problem, just the worst case scenario.
That is precisely the benefit of open collector - they allow easy combining of multiple signals.
No, I mean that pretty much any 4-connector twisted pair cable will already have the twisted pairs physically in the right configuration, it is just a question of connecting them up in a star quad configuration.
As far as I understood, you have already decided to go for a 4-conductor twisted pair cable (so 2 pairs). All I am saying is that you don't need a cable especially labeled "star quad".
Yes, I have a set of 1.6mm2 wires that I want to connect to the terminals, 2 on each, 4 wires total per nc400.
So, it there an advantage in twisting them in a star quad configuration, or would it be as good (or better) to only twist them as two independent pairs, going to the same speakon terminals at the end (no biwiring, just plain 2 pole sepakeon).
So, it there an advantage in twisting them in a star quad configuration, or would it be as good (or better) to only twist them as two independent pairs, going to the same speakon terminals at the end (no biwiring, just plain 2 pole sepakeon).
Ah, sorry, I though you were talking about a 4-conductor cable between the amp enclosure and the speakers.
If you are using individual 1.6mm2 wires, then yes, it is better to twist them in a four-wire twist around a common (possibly imaginary) center, and connect them as "opposite" pairs (what is usually referred to as star quad).
I measured the size of the speaker clamp at the NC400 and its 6.7 mm at the inside. The srews used are M3, thus leaving a difference of about 6.7 - 3.0 = 3.7 mm at the most. This means appr. 1.85 mm on either side of the screw. That would be appr. the diameter of a 2.5mm² copper conductor, solid or stranded. The inherent resistance of such a cable would be about 7.5 mOhm/m or 0.75 mOhm for a length of 0.1 m.
Using a solid conductor would make twisting the cable a lot tighter and easier, because the loop could be minimized by using the opposing inner sides of both speaker clamps. The cables would probably never be moved much after mounting it anyway. Any comments about this or does everyone prefer stranded wires ?
Using a solid conductor would make twisting the cable a lot tighter and easier, because the loop could be minimized by using the opposing inner sides of both speaker clamps. The cables would probably never be moved much after mounting it anyway. Any comments about this or does everyone prefer stranded wires ?
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I am totally OK with solid wire - at these distances, the surface effect will not really be an issue.
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