Ncore amp

[dan92075]

Moving the discussion on Ncore amp to a dedicated thread.

 

What are people's thoughts on this amp, both the diy NC400 and the NC1200?

 

I will share my experiences as well. . .

[realhifi]

Moving the discussion on Ncore amp to a dedicated thread.

 

What are people's thoughts on this amp, both the diy NC400 and the NC1200?

 

I will share my experiences as well. . .

 

Looks like you may be the one with the experience with these beasts. Obviously they have gotten press that is over the top and from the 6moons review you would think the had reinvented solid state amplification.

 

Don't be shy, tell us what you think.

[Blake]

Yes, I am with David, Dan please let us know your thoughts. Barrows, you too!

[barrows]

I have built an Ncore 400 stereo amplifier. One can see the details of my build at the audio circle forums: hypex owners circle-show us your Ncore thread.

 

I am still experimenting with the amp, trying to get the best out of it. For reference, my other two amplifiers I use for comparison are a refurbished and slightly modified PS Audio Classic 250, and a Pass Labs X 150.5 (current version). Both of these amps are class A/B and run in class A for the first handful of watts. The C-250 is FET input, bi-polar current stage, and the Pass is FET input with a MOSFET current stage. I run all the amps balanced, and they are all balanced input circuits (although only the Pass is balanced on its output).

So far the Ncore beats both other amps on ultimate resolution, and low noise floor (in fact, the noise floor is basically non-existent in reality). The Ncore will result in one discovering musical details they had not noticed before, the kind of details where once discovered, I hear them with the other amps, but it took the low noise and high resoltion of the Ncore to first discover them. This is a very intersting amp, and it seems to be very sensitvie to build approach, cabling, vibration, and tweaks. I am still working on it, trying to get it to where I want it to be.

So far, the drawback of the Ncore seems to be in terms of body, and natural warmth. I run amp direct, from a solid state, very neutral sounding DAC (but opamps style etched digital crap sounding DAC). I am not looking for a syrupy warmth, just the natural body and warmth that real instruments deliver. Note, that a lot (but not all) the folks over at audio circle who are really digging the Ncore are using tube preamps, it makes me wonder if tube pre amps are actually adding some coloration, which is masking what I think is a somewhat threadbare sound (a little bleached) in the Ncore-but, one cannot be sure about such things.

Bruno Putzeys, the designer of the Ncore, has outright stated that he made this amp to be as neutral, and without any coloration, as possible. He has also stated that it would be possible for him to make it sound any way he wanted. Note, for sure, the Ncore needs to be powered up for at least 24 hours before listening, anyone who listens to it without this warm up period is very likely to be disappointed. Next on my experiment list is to transformer couple the input, I am hoping that this may bring more body to the equation. I really want to switch full time to the Ncore, as I really hate using the large, energy wasting, traditional style amps...

[untangle]

I agree with barrows fully on his assessment of the NC400.

 

I would add that I detect no trace of "Class D" artifacts. If it sounds like anything, it sounds like a clean-and-hyper-detailed (high feedback) solid state amp. A bit acetic, but clean and powerful.

 

Lots of bang for the buck. I have not heard an NC1200.

 

Bob

[bhobba]

I got one to check out based on the hype. It's OK, good value, but a giant killer it aren't. A bit deadpan, slow and dull. Easily beaten by, the admittedly much more expensive stuff, we compared it to, such as a Spectron and MAC 501. Closer to stuff in its price bracket but a NAKSA 80 or Arion S250 is still better in my view.

 

I really am scratching my head why people went ga ga over it. There will be an amp GTG out my way soon and it may be there (the issue is everyone and their dog wants to bring an amp so a bit of rationalization will probably occur) and that may show a different result but I am not optimistic. When I checked it out before it was in three sessions with two other very experienced audiophiles, as well as having it in my system for an extended period, so it wasn't just my view.

 

Thanks

Bill

[bhobba]

I run amp direct, from a solid state, very neutral sounding DAC (but opamps style etched digital crap sounding DAC).

 

That's one thing I have to say about the NCORE. When I had it it was an entirely different amp fed direct from a DAC - I much preferred it that way.

 

And when I posted my finding on the amp in that really long thread on Audiocircle the designer did reply. He thought the deadpan quality I found was actually how he designed it to be neutral and understood because of that why it would be tough to compare it to MAC 501's which has a valve style output transformer that add's, according to some, euphonics. Maybe - but that's not what it sounded like to my ears and didn't explain why the Spectron was easily better.

 

Thanks

Bill

[barrows]

That's one thing I have to say about the NCORE. When I had it it was an entirely different amp fed direct from a DAC - I much preferred it that way.

 

And when I posted my finding on the amp in that really long thread on Audiocircle the designer did reply. He thought the deadpan quality I found was actually how he designed it to be neutral and understood because of that why it would be tough to compare it to MAC 501's which has a valve style output transformer that add's, according to some, euphonics. Maybe - but that's not what it sounded like to my ears and didn't explain why the Spectron was easily better.

 

Thanks

Bill

 

First, I made a word ommission in the description of my DAC's output stage, I meant to say that the output stage is not based on crappy, etched sounding opamps. It is a discrete output stage with no global feedback.

As to the MAC (McIntosh) amps, well, they have output transformers, and there is no question that an output transformer adds distortion, raises output impedance, and lowers damping factor. The Ncores are characterized by ultra low distortion, ultra low output impedance, and very high damping factor: from a technical standpoint, one would expect these two amps to sound very, very different, so it does not surprise me that one would find them to be different in a listening test.

I am not going to be so sure about saying one amp is "better" than another, as this is all about preferences and system matching.

[coxhaus]

I have never heard the NC1200 amps but I use digital Spectron amps. I run a Joule tube preamp and I am not sure I would want to run a solid state preamp with my digital amps. The other thing I have found is to run a power isolator for each of my amps. I have dedicated 3kVA power isolators for each amp.

[dan92075]

I completely agree with barrows description of the NC400.

Extremely low noise-floor compared to any other amp I have used, and very low distortion, and very neutral.

I have used various flavors of Class D ICE amps (Wyred, Bel Canto 500m, etc) and they all seemed to have weird distortion issues at high frequencies, which are revealed in measurements as well.

Compared to Spectron, the NC400 does not seem to have the same energy - the Spectron was a little more of an exciting amp. However, the Spectron did not get the treble region perfectly correct - its better than the ICE amps for sure, but there is a certain dryness to the Spectron sound that I believe is because it can't do the higher frequencies just right.

 

The NC400 does everything right - the treble frequencies are correct - but agree that it seems to somehow lack a bit of energy.

Nevertheless, I did some back to back comparisons to some good Class AB amps, including Simaudio and Cary, that cost much more, and it was actually very comparable, so overall it is very good value for the money.

 

But obviously, I was not completely satisfied - so I tried out the NC1200.

The NC1200 (Merrill based), was a revelation. It has all the best properties of the NC400 (low noise, low distortion, etc), but also has a wealth of energy. Immediately, I heard music in the 200-400Hz region that was so recessed before, that I never noticed was there on any amp - that took me by surprise.

This amp is similar to the Spectron in that regard - copious amounts of energy.

Unlike the Spectron however, there is no dryness to the sound - as with the NC400 this is the first Class D amp that gets the high frequencies perfectly correct.

But what I found amazing about the NC1200 (unlike the NC400) is it is so much smoother - almost analog sounding. The increase in energy I expected (its rated twice as much after all), but the smoother analog sound was something that definitely was a surprise.

 

So overall, I can say I am finally done with my amp search. I have not heard the giant amps, but find it hard to imagine any amp doing significantly better than the NC1200 - it does every aspect of an amp very, very well.

[cjf]

Well, I too run a DIY NC400 setup and they replaced my previous PASS Labs X250 amp.

 

In terms of the lack of energy previously mentioned, I resolved that by building X 4 of them and running them in a Quad amp setup on my B&W's. Much cheaper then the Merrill setup in terms of cash outlay. I haven't heard the Merrills so I can't comment on if they sound any better or not.

 

You can see some pics in my sig.

[coxhaus]

I completely agree with barrows description of the NC400.

Extremely low noise-floor compared to any other amp I have used, and very low distortion, and very neutral.

I have used various flavors of Class D ICE amps (Wyred, Bel Canto 500m, etc) and they all seemed to have weird distortion issues at high frequencies, which are revealed in measurements as well.

Compared to Spectron, the NC400 does not seem to have the same energy - the Spectron was a little more of an exciting amp. However, the Spectron did not get the treble region perfectly correct - its better than the ICE amps for sure, but there is a certain dryness to the Spectron sound that I believe is because it can't do the higher frequencies just right.

 

The NC400 does everything right - the treble frequencies are correct - but agree that it seems to somehow lack a bit of energy.

Nevertheless, I did some back to back comparisons to some good Class AB amps, including Simaudio and Cary, that cost much more, and it was actually very comparable, so overall it is very good value for the money.

 

But obviously, I was not completely satisfied - so I tried out the NC1200.

The NC1200 (Merrill based), was a revelation. It has all the best properties of the NC400 (low noise, low distortion, etc), but also has a wealth of energy. Immediately, I heard music in the 200-400Hz region that was so recessed before, that I never noticed was there on any amp - that took me by surprise.

This amp is similar to the Spectron in that regard - copious amounts of energy.

Unlike the Spectron however, there is no dryness to the sound - as with the NC400 this is the first Class D amp that gets the high frequencies perfectly correct.

But what I found amazing about the NC1200 (unlike the NC400) is it is so much smoother - almost analog sounding. The increase in energy I expected (its rated twice as much after all), but the smoother analog sound was something that definitely was a surprise.

 

So overall, I can say I am finally done with my amp search. I have not heard the giant amps, but find it hard to imagine any amp doing significantly better than the NC1200 - it does every aspect of an amp very, very well.

 

The way to get good sound from Spectron amp's treble is to use power isolation. The treble is very good sounding after adding a large power isolator. I use 3kVA for each amp. Of course to get the best from any amps you need good power cords, Still points, and room treatment but I assume this is a given. This is probably true for all class D amps but I have never heard the NC1200 amps. Maybe one day I will get to hear them.

[dan92075]

Well, I too run a DIY NC400 setup and they replaced my previous PASS Labs X250 amp.

 

In terms of the lack of energy previously mentioned, I resolved that by building X 4 of them and running them in a Quad amp setup on my B&W's. Much cheaper then the Merrill setup in terms of cash outlay. I haven't heard the Merrills so I can't comment on if they sound any better or not.

 

You can see some pics in my sig.

 

Looked at your pics - it looks like you are bridging your NC400's - is that correct?

[dan92075]

The way to get good sound from Spectron amp's treble is to use power isolation. The treble is very good sounding after adding a large power isolator. I use 3kVA for each amp. Of course to get the best from any amps you need good power cords, Still points, and room treatment but I assume this is a given. This is probably true for all class D amps but I have never heard the NC1200 amps. Maybe one day I will get to hear them.

 

Agree - every Class D amp I have ever tried has been very sensitive to power cords.

Both the NC400 and the NC1200 are no exception.

I have found the Lessloss Signature to work well with every Class D amp.

[Blake]

Agree - every Class D amp I have ever tried has been very sensitive to power cords.

 

This was my experience as well with some Class D amps I used to own, Bel Canto REF 500, and PS Audio HCA-2.

[Julf]

Agree - every Class D amp I have ever tried has been very sensitive to power cords.

Both the NC400 and the NC1200 are no exception.

 

I have to disagree. I have found that my nc400's are not affected by the power cords as long as the cords are heavy duty enough. What I have found is that the nc400's don't like power filters (that probably limit current).

[PeterSt]

I never listened to the NC1200 but measured it. Then I just did not want to listen anymore.

 

Beyond the audio band, high frequency (square) monsters go up and up and up (looks like DSD), and for me it is clear that there's a low pass filter active to tame that in-audio band; there's a roll off visible towards 20Khz (I forgot where this starts). Beyond-band various frequencies are visible which I don't like to have (even) there. But this is Class D in general.

 

In-band THD+N is totally neglectable, and specs are correct on that matter (0.00073% from the DAC becomes 0.00079% on the outputs (1KHz)).

 

From the pair I ordered one was broken in a way that didn't make sense to me and which would not be visible to a normal user (shortcut when no signal present), and the replacement was also broken. Support ? I'm disappointed.

Here I stop, but there is more. I don't think I would have written this when support would have been on par.

 

Sorry I did not listen.

Peter

[barrows]

Let's investigate power cabling more. Take a look at the stock provided AC cable for the SMPS 600, it is 18 AWG. So now consider a stereo amp build, one would have 2x 18 AWG for the AC input, that equals 15 AWG. So, compared to most power cords (even the most basic OE ones are usually 14 AWG) the input wiring of the SMPS 600 is going to be the bottle neck.

I changed the input wiring on my amp to 15.5 AWG, which is about all one can fit into the SMPS 600 PCB. So I have 15.5 x 2 in my stereo amp build, for aggregate gauge of 12.5 AWG. So even in my case, an 11 AWG power cable would appear to be totally adequate (I am using a 9 gauge cable, as that is what I have built right now).

I wonder if the differences people hear with power cords are the result of the amp sounding different, or the result of the power cable broadcasting differing amounts of RF (from the amp) into the air, and back onto the AC mains. SMPS are pretty good at isolating their output from mains borne noise, as they are heavily filtered by necessity. I am leaning towards the idea that the power cable with the Ncore is more likely to affect the sound of the system by what noise it is allowing out into the air, and back onto the mains. So, perhaps special attention should be paid to the shielding design of the power cable.

[Julf]

I never listened to the NC1200 but measured it.

 

Care to share your measurements with us?

[coxhaus]

I think we are getting technical enough about power for amps where I would like to inject that I feel 30 amp breakers sound better than 20 amp. I run 30 amp 220volt breakers feeding into my 3kVA power isolators.

 

I also run a 5kVA power isolator for my other gear split in half where half is for digital and the other half is for analog. I have all digital and analog totally isolated from each other.

 

This keeps the digital amps and other digital gear from feeding back into the AC system.

[christopher3393]

Wondering if anyone has heard the Auralic Meraks?

 

AURALiC

 

6moons audio reviews: AURALiC Merak

[Julf]

I think we are getting technical enough about power for amps where I would like to inject that I feel 30 amp breakers sound better than 20 amp. I run 30 amp 220volt breakers feeding into my 3kVA power isolators.

 

And your house wiring can take 30 amps?

[coxhaus]

And your house wiring can take 30 amps?

 

All my wiring for my system was installed for this purpose and is dedicated for my stereo system. It is all 10 gage separate runs.

[Julf]

All my wiring for my system was installed for this purpose and is dedicated for my stereo system. It is all 10 gage separate runs.

 

All the way to the transformer? Sweet!

[PeterSt]

Care to share your measurements with us?

 

I did not make screenshots Julf. My posting about it is just because I accidentally know (from 3 weeks back btw), and not to form a story or bashing (which I am doing now anyway I guess).

 

I wanted to use them for some project, and the first thing I learned was that one module consumes 90 Watts ?? (at a gain of 20). Completely ridiculous in my view, beyond my understanding and here again : no help other than "that should be less".

So 90 Watts for Class D ? and then to imagine that I needed 6 of them for that project.

Class A does better in that realm.

 

I have also a little history here, because 4-5 years or so back I investigated all the Class D (and T) amps, and all hopelessly failed for one reason or the other. The uCD700 "audiophile" version was made for me back at that time, but it never saw life when I was waiting for it. So I heard them all, but not that one.

This was my first re-attempt but got slapped in the face.

 

Regards,

Peter

 

 

PS: Might it come to Hypex doubting my measurements, I am all ready for that. No stupid shouting from me ever.

And as I said, there is more. At least one CA forum member (NC1200 owner) knows what I am talking about and if he likes he can speak up. I won't point him at this thread though.