[cab]

Think loop and EMI.....

[gstew]

I've seen this mentioned a number of times, but have a slightly different interpretation...

What Bruno wrote was:

"correct: do twist the speaker wiring and PLEASE do not have them come out of the opposing sides of the screw lugs. This makes a big pickup loop right next to the output inductor."

I take this to mean that you do want the speaker wire twisted and you don't want to have them coming out of the opposite sides of the lugs. And that this is to reduce the pickup loop size.

Given this, I suspect coming off the same sides of the lugs toward the center of the module is ok, same sides of the lugs away from the center of the module is better (loop farther away from EMI-producing parts), and near sides of the lugs would be best (very little loop if they are twisted tightly from there).



You can't see it from this angle, but the wire rises straight up from the lugs about 1" before curving towards the output connectors in my implementation.

My 2 cents.

Greg in Mississippi

[jmbulg]

Thanks again to all who helped w/ideas and input and answers to questions!

Mark

Very nice cases!. I would however twist the loudspeaker cables differently: you have twisest two positive cables(red greeen) with each other and also two negatives (blue white) which is meaningless.
The twisting is meant to help cancel radtion from positive and negative to cancel.

So you should twist
red with blue   
green with white
(and possibly twist the the two twisted pair together for the final touch).

An as other say, avoid the large open loop between positive and negative cable at the connector

[audio-heaven]

Very nice cases!. I would however twist the loudspeaker cables differently: you have twisest two positive cables(red greeen) with each other and also two negatives (blue white) which is meaningless.
The twisting is meant to help cancel radtion from positive and negative to cancel.

So you should twist
red with blue   
green with white
(and possibly twist the the two twisted pair together for the final touch).

An as other say, avoid the large open loop between positive and negative cable at the connector

Absolutely jmblug is right, to cancel noise the positive and negative should always be twisted together.

[mkcarnut]

Did you follow the link that I provided?  See the picture?  See the quote from Bruno?  I don't know what else to say.   

I followed the link, but the picture was not able to load.  Looks like it's no longer linked.  Hence my response...sorry if it upset you for me to re-ask, but with what I could see your input was not (and still is not understood).  I even scanned several pages back and forward in that chain to hopefully find more.

To the others who elaborated - thanks for the correction on the winding...I get that - my mistake as I got twisting away not thinking about that!

As far as the other point jwtrace was making...I can easily move the line that's enters the neutral side to the other side.  No big deal there, but from the comments from others it sounds like 1 school of thought is for them to come out of the same sides of the output connectors (which is what Bruno said) and another is to reduce the gap between the sides, which would mean both should be connected from the middle of the output connectors.  Did I interpret the comments right?  In any case, either way I go - the distance between the 2 sets of wires is shorter than they are now and no wire will go over the EMI-producing circuitry.

I'm not having the slightest issue w/any hum or noise right now, but I'll just go move the one to the center to match what Bruno said as I re-twist the wires.  It's easy enough to do.

Mark

[jtwrace]

I followed the link, but the picture was not able to load.

Originally Posted by Bruno Putzeys 
do twist the speaker wiring and PLEASE do not have them come out of the opposing sides of the screw lugs. This makes a big pickup loop right next to the output inductor.

[jtwrace]

As far as the other point jwtrace was making...I can easily move the line that's enters the neutral side to the other side. 

I'm not speaking anything about the power side. As I said above, the output wires.

[cab]

There are three possibilities: opposite outsides, opposite insides, one outside/one inside. The goal is to make the loop area as small as possible. Which arrangement accomplishes this? If tightly twisted, it is the opposite insides position.

[studley]

Originally Posted by Bruno Putzeys 
do twist the speaker wiring and PLEASE do not have them come out of the opposing sides of the screw lugs. This makes a big pickup loop right next to the output inductor.

The confusion about this arises from the differing interpretations of Bruno's use of the word "opposing" (as distinct from opposite which is open to even wider interpretation).  I believe in this context opposing means facing one another i.e. the inside entry points into the 2 lugs.  Hence the correct wiring shown in the picture shows one wire entering from the inside of the lug  and the other wire entering from the outside of the lug.  So if I'm right, and I've understood what gstew was saying correctly, then he has got it wrong.

PS. Tripe Face Boogie via my ncores sounding great as I type this   

[cab]

Disregard the words and focus on the intent. If you wire these to minimize the loop area, you will have the correct arrangement. Is there a loop in the above photo?

[jonbee]

Built my amp yesterday. After obtaining all the parts, it took me about 5 hours, and worked fine right off the bat.
Kudos to all for their input, and particularly to member HT cOz for his chassis (see his ad in the Commercial Zone for more info). Having the case precisely cut, drilled, and countersunk saved a ton of work.


Nothing too special here. I used Cardas copper speaker terminals, WBT solder, neutrik xlr. Speaker terminal wire is a hybrid 5 nines silver and PCOCC copper/foamed teflon. (I've re-twisted and re-routed the AC leads slightly since this pic was taken.)
It sounds quite nice out of the box, a bit forward in the upper mids overall, but very similar to Jason's monoblocks as far as I can recall. My feeling is that while this amp as it sits is not the best I've heard in all areas,  and perhaps not over all, it takes the honors for my needs and budget. For under $1800 total, plus my labor there is no competition new or used that I've heard for my system, taste and purposes. The transparency, dynamics, immediacy and bass control are truly remarkable.
I'm using a new (for me) balanced preamp (Bel-Canto Pre3) and XLR ICs (Discovery Essence) with Acoustic Zen Satori bi-wire and my Selah Tempestas. I need to let it run in for quite awhile before I embark on any changes. Right now I'm really enjoying the music. 

I want to thank Jason again for the tour. I'd been a class d amp user for a long time (this is my 9th or 10th), and have eyeballed the n-cores with great interest. There's no substitute in this hobby for hearing a prospective component in one's own setup, and his offer was a godsend.

BTW, can anyone comment on how their sound quality changed during burn in?

[gstew]

Originally Posted by Bruno Putzeys 
do twist the speaker wiring and PLEASE do not have them come out of the opposing sides of the screw lugs. This makes a big pickup loop right next to the output inductor.

Just to be clear on where I was coming from....

The text I quoted by Bruno is in post #2840 of the monster DIYAudio NCore thread.

The picture that is often shown associated with Bruno's remarks is in a post by Mr_Push_Pull, #2846 of that thread. The picture appears to be taken from a shot of an NC400 Bruno is holding from the 6Moons Audio Industry Features piece on the NCores. But it was not posted by Bruno as an example supporting what he said.

Again, all Bruno said was "do twist the speaker wiring and PLEASE do not have them come out of the opposing sides of the screw lugs".

He never said have them come out of the same side of the lugs, even though he does show one wired up that way in another context.

The common interpretation of Bruno's comment seems to be 'Having the wires coming from the same sides of the lugs'.

My interpretation is 'minimize the non-twisted portion of the speaker wires'. This can also be done by bringing them from the adjacent sides of the lugs and if done correctly, can better minimize the non-twisted portion.

Bruno, if you are reading this, feel free to differ with me! Sorry, not trying to cause a controversy here!

Greg in Mississippi

[saisunil]

Nothing too special here. I used Cardas copper speaker terminals, WBT solder, neutrik xlr. Speaker terminal wire is a hybrid 5 nines silver and PCOCC copper/foamed teflon. (I've re-twisted and re-routed the AC leads slightly since this pic was taken.)

I'm using a new (for me) balanced preamp (Bel-Canto Pre3) and XLR ICs (Discovery Essence) with Acoustic Zen Satori bi-wire and my Selah Tempestas. I need to let it run in for quite awhile before I embark on any changes. Right now I'm really enjoying the music. 

That sir is special!

[mkcarnut]

jonbee - looks great!

Others debating the "opposing"...the comment above ("The confusion about this arises from the differing interpretations of Bruno's use of the word "opposing"...") rings home to me from my first read of the "manual" for the 400's and power supplies.  I found a lot of wording that for me I could interpret more than 1 way.  Luckily - with help from you guys who have studied this a bit more than others + the pretty good pace of responses from Hypex, we can get that wording clarified.

I'm going to move mine to the location jwtrace shows in that photo and be happy.  Heck, I'm happy now - mine sounds great...no noise at all and very good detail in all forms of music I have tried.  I would not even bother to do that, but I had a little "cleanup" to do inside each case anyway so I'll take an added 5 minutes to re-twist my wires and reconnect them in the spots shown.

Mark

[Phil]

It sounds quite nice out of the box, a bit forward in the upper mids overall, but very similar to Jason's monoblocks as far as I can recall.

BTW, can anyone comment on how their sound quality changed during burn in?

Although some have said burn-in is a matter of hours, in my system it seems that something like 200+ hours were needed (maybe more, I didn't track it closely since, overall, the sound was good out of the box and only got better) until the HF was not too forward.  Two factors may be at work here:  my ears (very fussy with HF) and the speakers (tend to highlight forward HF).  The speakers also highlight any noise.  Given there is no noise with these amps, it all sounded excellent after 50 hours or so (seemed to cycle through the typical burn-in before that).  Could this also be a factor of binding posts, etc. used?  Don't know.  Do run them in at high-ish volume when you can.  Please let us know if they change in a month or so.

Eventually, you might want to try one Audio Magic Pulse Gen X inside the case:  http://www.audio-magic.com/Prod-PulseGenZX.html

Phil

[jonbee]

Eventually, you might want to try one Audio Magic Pulse Gen X inside the case:  http://www.audio-magic.com/Prod-PulseGenZX.html
Phil

I've been looking at those. Do you use it?

[Phil]

I've been looking at those. Do you use it?

I do.  Had it installed with a switch and the switch is now always in the ON position.   
YMMV, but had verification from one other listener that is makes a positive change. 

[satfrat]

I do.  Had it installed with a switch and the switch is now always in the ON position.   
YMMV, but had verification from one other listener that is makes a positive change.

 

[ajst2duk]

In keeping with the "fire in the hole" theme - nowhere near as creative as the most recent additions though, my hat is off to you guys.

[jonbee]

It sounds quite nice out of the box, a bit forward in the upper mids overall, but very similar to Jason's monoblocks as far as I can recall.

Just a quick update-
After ~30 hours on the amp, all trace of excess forwardness is gone. I have no complaints at all with this amp; the change from my cullen modded Icepower PS Audio GCC500 amp is an unqualified success.
While the nCores do not do everything better than the best I've heard in every aspect of reproduction, overall they are most satisfying, in a very practical and well priced package.
Certainly the PS Audio amp, which I used happily for 3 years is not shamed by the Ncore, but the Ncore brings me closer to all the music, with no downside.
I could easily leave well enough alone, but at some point I will replace the stock power input and signal input wires, upgrade the IEC and XLRs, and maybe add the audio magic gadget. I'm in no hurry to do so, however. I've got so much music to listen to!