Hypex Ncore

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Didn't Bruno describe that the NCore improvement over the UCD in the bass an illusion since it is the improved top end that makes the difference?

If I remember correctly he himself was not convinced that the NCore beats the UCD in the bass when used in an active system.
oh, you're right, I remember now that he wrote something like that. but I'm not sure I get the 'active' part. :confused:

I'd be interested to know if it's top-end or mids, mid-highs etc that give that illusion. I have read before that certain kinds of distortions can have unexpected effects.
 
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oh, you're right, I remember now that he wrote something like that. but I'm not sure I get the 'active' part. :confused:

I'd be interested to know if it's top-end or mids, mid-highs etc that give that illusion. I have read before that certain kinds of distortions can have unexpected effects.

When active I mean if it's used only for the bass region. I think the discussion was about using NCore for a sub where Bruno suggested an UCD, standard edition I think since a NCore would be mostly overkill without convincing improvement. If I remember correctly the he theorized that the improvements of the NCore would become apparent in the midrange and upwards.
 
With that connector unplugged from the amp I have absolutely no white noise.
With a 1k ohm resistor shorted across the hot/cold of the input I have no white noise.
So your problem is solved and you know your amp is in perfect working condition.

Now, or you figure out why your input cable inside your amp act like an antenna (loop ground or shield problems) or you just forget about that, because your source will present an impedance far less than 1KOhm.
 
So your problem is solved and you know your amp is in perfect working condition.

Now, or you figure out why your input cable inside your amp act like an antenna (loop ground or shield problems) or you just forget about that, because your source will present an impedance far less than 1KOhm.


With the source hooked up to the amps input I still get the white noise though, should it not be silent if the source has an output impedance of less than 1k ohm?
 
Now, or you figure out why your input cable inside your amp act like an antenna (loop ground or shield problems) or you just forget about that, because your source will present an impedance far less than 1KOhm.

I think the experiment with the 1K resistor also shows the cable is *not* acting as an antenna - even with the cable in place, and terminated with a 1 K resistor at the input XLR plug, there was no noise.
 
With the source hooked up to the amps input I still get the white noise though, should it not be silent if the source has an output impedance of less than 1k ohm?

Even with the source turned off? And unplugged? That would indicate that the output circuitry (or cabling) inside your source is picking up the noise. Is the DAC placed near anything that could be causing electrical noise?
 
Even with the source turned off? And unplugged? That would indicate that the output circuitry (or cabling) inside your source is picking up the noise. Is the DAC placed near anything that could be causing electrical noise?

Julf, did not try it with the dac off, will do that when I get home from work.

The dac is sitting on the amp for my subwoofer for my 5.1 setup but that amp is never on unless i'm watching a movie.
 
that's weird.
have you ever used the Mytek with other electronics? have you checked with headphones (I see it has a headphone out)? when you connected the 1k resistor at the input, was it after a cable run or directly at the board connector (or XLR in)? so far what you're writing is implying that this a result of NCORE+Mytek interaction. how about some pics? that might avoid a long forum ping-pong game.
 
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Julf, did not try it with the dac off, will do that when I get home from work.

Looking forward to hearing how that goes!

The dac is sitting on the amp for my subwoofer for my 5.1 setup but that amp is never on unless i'm watching a movie.

But the 5.1 amp is still plugged in? It might still have parts of the power supply and logic circuits "alive" even when in stand-by/"off".

Just to be sure (and I might have asked this before), is everything powered from the same power outlet?
 
Looking forward to hearing how that goes!

But the 5.1 amp is still plugged in? It might still have parts of the power supply and logic circuits "alive" even when in stand-by/"off".

Just to be sure (and I might have asked this before), is everything powered from the same power outlet?


Ok, with the dac output plugged into the ncore but leaving the dac off I still have the tiniest bit of white noise. I have to very close to hear it, but honestly it is very little.
However, when the dac is powered up then all the very audible white noise comes back and so do the loud pops on power up/down of the amp.

The amp the dac was/is sitting on is not powered up at all, I have a furman "power conditioner" (really just a surge protector), that takes a 12V input to power on some plugs that powers up the subwoofer amp, so that amp never has power unless my 5.1 amp is on.

With regards to the outlets, the amps are plugged directly into the wall to a 20amp dedicated circuit.
The DAC has been plugged into those same outlets, plugged into a different circuit, has been plugged into the furman power conditioner/surge protector which was on the 20A ncore circuit and also plugged into the furman which was plugged into a different circuit. Every combination yielded the same result.


mr_push_pull said:
have you ever used the Mytek with other electronics? have you checked with headphones (I see it has a headphone out)?

No I have not, probably worth trying.

when you connected the 1k resistor at the input, was it after a cable run or directly at the board connector (or XLR in)? so far what you're writing is implying that this a result of NCORE+Mytek interaction. how about some pics? that might avoid a long forum ping-pong game.

The 1k resistor was added at the end of the input cable. I grabbed a male xlr connectors, soldered the resistor to the xlr and plugged it into the back of my amps female xlr input.
 
Ok, with the dac output plugged into the ncore but leaving the dac off I still have the tiniest bit of white noise. I have to very close to hear it, but honestly it is very little.
However, when the dac is powered up then all the very audible white noise comes back and so do the loud pops on power up/down of the amp.

OK, so we have proven that the problem is the DAC, not the amp.

Any chance of borrowing an audio isolation transformer?

The 1k resistor was added at the end of the input cable. I grabbed a male xlr connectors, soldered the resistor to the xlr and plugged it into the back of my amps female xlr input.

Good way to do it.
 
Nope can be very cheap, try googling "DI box", be careful to select one that uses xformers and look at the F response / distortion, look for passive ones.

Something likes this should work: ART Pro Audio Just an example!

Indeed. And that one has the benefit of providing -20 dB of attenuation to better match the gains in your setup (ideally you want -10 dB). The downside is that that one has single-ended input jacks.

Here is another: Whirlwind ISO-XL Line Isolation Transformer - it is XLR to XLR, but no attenuation.

The big brand name is Jensen, pricey, and I haven't found a suitable XLR-to-XLR, balanced 1:5 one in their range.

But before you buy anything, I would try to borrow one (or rent one from a pro audio / music store) to see if it actually helps.
 
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