The Hypex nCore build thread

[Akasha]

I just don't get the circular circuit board that you cant bolt to a heat sink?
If this board is heat dependant why don't they design it so you can bolt it to a case heat sink FFS ????
Alan

no problem to bolt onto a heat sink just because its circular, heat sink doesn't have to be
long mounting bolts even applied with the Ncore if I remember correct

 

[occamsrazor]

Thanks all for the cable advice... For the XLR cables I think I'll just go for the Canford star quad. For 20 quid per 10m terminated it's hard to beat.

Which cases did you go for? I'm tempted to go for the Ghent ones.

Yeah I went for the Ghent cases in black (they do silver also). More expensive than the Silcon Ray but I much prefer the design. Their eBay page doesn't show great quality photos, but assuming its similar to all their other cases you can see better photos on their website, and it appears at least to be quite well made. By the way Ghent is very responsive to emails.

 

[Julf]

no problem to bolt onto a heat sink just because its circular, heat sink doesn't have to be
long mounting bolts even applied with the Ncore if I remember correct

Indeed. Mine are bolted to the finned sides of my enclosures.

 

[Julf]

Case IEC connector > power supply: I believe I can just use standard mains cable for this. Remove the plastic cover and twist the two blue/brown wires. Yes? If so, I have some already.

Or just use standard house wiring stuff.

XLR input connector > amp module: Someone said this is included but it looks different on each build picture I see. I believe this does NOT need to be twisted (correct?) but is shielded. Recommendations?

There are two versions. Hypex initially included one version, then upgraded it (and sent the upgraded one for free to owners of the old one). Because it is shielded, it does not need to be twisted.

Amp module > speaker binding posts: Someone recommended teflon insulated silverplated copper, alternatively just copper. Another recommended 2mm core. Recommendations?

Pretty much only recommendation is thick enough / low impedance enough, and thin enough isolation that it is easy to twist in a neat, tight twist.

MDAC > Ncore: As I want to run long XLR cable from MDAC to monoblock, then short speaker cable to speaker, I need a pair of XLR cables of around 8-10m each. Someone suggested star quad cable. What about this?

I use shielded cat 6 ethernet cable, as I needed multi-connector cable for my active setup. Nicely twisted, and if it is good for 1 GHz, it is good enough for music.

Ncore > Speakers: Will only need 0.5-1m, I will use my existing speaker cable for now (some old QED 79), unless I can buy 2x1m of better for good price at same shop as the rest of this stuff.

At those lengths it really won't be an issue, but one of the great things (especially compared to most "traditional" feedback-before-choke designs) is the low output impedance / high damping factor. Make sure you don't waste it on thin, high-impedance cables - use thick enough ones without any fancy trickery.

 

[Nick1881]

As I wrote, the thermal protection only kicks in at +95C, but specified max operating temperature is +50C. If your enclosure is warm to touch, you are probably hitting the +50C, possibly shortening the life of the electronics (usually the electrolytic capacitors are the ones suffering the most).

I have pretty good ventilation in my enclosures, and have checked temperatures, but I still switch my amps into smps standby when not listening. I haven't noticed any warm-up effect on the sound quality.

Hi Julf, I missed this reply yesterday.

How do you put your units into SMPS standby? Do you have an extra switch or something?

Thanks

I have also ordered the Ghent cases.

 

[Julf]

How do you put your units into SMPS standby? Do you have an extra switch or something?

It takes more than just a switch - you need an external voltage. I get it from my digital source, so everything turns on when I turn the source on.

 

[Nick1881]

It takes more than just a switch - you need an external voltage. I get it from my digital source, so everything turns on when I turn the source on.

That's what I need to do, could I do it with the 12v trigger from my AV amp? Could you tell me how to wire it in please?

Thanks

 

[occamsrazor]

It takes more than just a switch - you need an external voltage. I get it from my digital source, so everything turns on when I turn the source on.

Could you explain a bit how you are doing this please? it sounds like a nice solution. Bemused's solution was nice too, though it required an additional board - what does yours use? If there's something simple I may try, if not I'll just use one of those "intelliplugs" that senses the current use of the DAC, although that'll be messier in terms of running an extra power cable. Thanks.

 

[occamsrazor]

I have also ordered the Ghent cases.

Do you have an existing ncore setup and will be transferring the modules to the new cases? Or you are building a new amp from scratch like me?
Either way you'll likely get your cases a while before I do, so I'll be very interested to hear anything interesting you discover about them or tips and tricks in fitting stuff etc.

 

[Nick1881]

Do you have an existing ncore setup and will be transferring the modules to the new cases? Or you are building a new amp from scratch like me?
Either way you'll likely get your cases a while before I do, so I'll be very interested to hear anything interesting you discover about them or tips and tricks in fitting stuff etc.

I currently have a single NC400 powering my centre channel for AV use. I've just ordered 2 x NC400 and 2 x SMPS600 to use in the new ones I'm making. I still need internal speaker wire and maybe some fancy WBT binding posts.

 

[sam_cat]

Could you explain a bit how you are doing this please? it sounds like a nice solution. Bemused's solution was nice too, though it required an additional board - what does yours use? If there's something simple I may try, if not I'll just use one of those "intelliplugs" that senses the current use of the DAC, although that'll be messier in terms of running an extra power cable. Thanks.

http://www.amazon.co.uk/dp/B00BTBET2E/?tag=pinkfishmedia-21

Its what I use and works very well. No trickery or clever wiring involved, plug stuff in.. Turn on the thing plugged into the master socket (in my case the Dac) and a moment later everything else turns on.

 

[Nick1881]

My new modules are due to arrive tomorrow, cases on Tuesday.

Here is a pic inside my current centre channel amp.

 

[Julf]

Here is a pic inside my current centre channel amp.

I keep pointing out that Bruno specifically recommended minimizing the loop the speaker output wires form at the output terminals. Your speaker cables both leave the terminals in the same direction (left in the picture) and form a sizeable loop before the twisting begins. That is an antenna for HF noise.

The recommendation is for the wires to leave towards each other (so the outer/left one in your pic should go inwards, to the right), tricky to do with cable that thick, but doable.

 

[Nick1881]

Yea, I was worried about it shorting as they are so tight. I don't like those clamps at all, I might remove them from my next builds, not sure if they need to be de-soldered from underneath though and how difficult it is to remove the heatsink.

 

[Julf]

Yea, I was worried about it shorting as they are so tight.

It is indeed very tight. Removing the heatsink is not that hard - just be aware that the switching transistor/fet is attached to the heat sink, with thermal paste in between.

 

[Nick1881]

UPS just dropped these off

 

[occamsrazor]

Pretty much only recommendation is thick enough / low impedance enough, and thin enough isolation that it is easy to twist in a neat, tight twist.

Re: what wire to use for the amp > binding posts. I must be really stupid because I've been searching online for days and still can't work out what to get. Maybe I'm worrying too much, but I just want to do it right the first time. I only want to buy a metre or two, not a reel.
It seems 4mm2 is about the largest you'd want and still be able to wire around the screws on the amp module? Or would you go smaller like 2.5mm2? Is something like this appropriate? I guess the problem with "normal" speaker cable is the insulation is too thick for twisting, is that right?

http://www.12voltplanet.co.uk/39-amp-single-core-thin-wall-auto-cable.html

...or can someone please give me an actual link to some stuff and put me out of my wiring misery

 

[Nick1881]

I'm going to use Neotech STDCT-12 its quite thick strands so fairly stiff, should twist ok though and stay in place well, it's quite expensive though, I ordered 1m, kinda wish I had ordered 2m and done double runs, it should be ok though I guess.

I ordered from Hifi Collective, give them a call, they delivered next day.

 

[timH]

Maplin XR36P Equipment Wire 32x0.2 Red £1.49 per metre
XR32K Black ditto

 

[occamsrazor]

Maplin XR36P Equipment Wire 32x0.2 Red £1.49 per metre
XR32K Black ditto

Nom. conductor area: 1.0 mm2
Max. working voltage: 1500 V rms
Max. current: 6 A (commercial rating 10 A)

I am not knowledgeable about these things, but looking at the NC400 specs it says peak output current is 24A. Wouldn't this Maplins cable be insufficient for that? Or am I mistaken? Thanks.