Class D

[iansr]

Thanks Gary. I should have them by next week. WILCO on the reveiw. I have the BMC monoblocks to compare them against. I believe the BMC monoblocks are top performers, so it should be fun.

VERY interested to hear (a) your impressions of the ncore and (b) comparison of the 2 power supplies.

 

[barrows]

A brief update on nCore. I am building a pair of nCore based monoblocks using the nCore DIY modules and the matching SMPS600. I did some preliminary listening to the modules (no cases, haphazard wiring) to make sure they worked. At first the sound was very good, with exceptional detail retrieval, with the exception of the high frequencies, which seemed a little veiled, and a slight lack in the low level resolution necessary to depict ambience.
After a few days of use, both these areas improved markedly, enough to make me consider nCore based amps for my own system, I am quite impressed, as these observations were made without proper wiring, or chassis.
These amps are being built for a friend, they should be finished within a week or so (I am still waiting for the back panels), and I will listen again (testing) for 24 hours or so before shipping them to their owner. I'll be happy to report my findings at that time.

My amplifier for reference is a Pass Labs X150.5, with Nordost Frey speaker cables, to Focus Audio FS-888 speakers. I use a custom music server running voyage/mpd, with a custom dual linear power supply, a very low noise independent supply feeds a SOtM USB out card in the server, and my DAC is a custom variation on a DIY Twisted Pear Audio Buffalo II, with a single input, a SOtM async USB receiver.

 

[Odyno]

Keep us posted on your decision!
I use 4 NCore witn 2 SMPS one power supply per channel and with those amps my system ever sounded beter.

 

[Occam]

I've been running my Ncore 400s, dual amp modules fed by 2 SMPS600, for 2 months now.
Subjectively -
- Excellent bass, although I do miss some of the 'phat' bass of my Aksa Lifeforce amp, a beautifully implemented Self styled Bailey architecture optimal bias AB bipolar output amp.
- Resolving mids and treble, but subjectively 'colder' than the above amp. Changing the tube dampers on the Siemens PCC88s on my E.A.R. Acute III cd player/dac from Herbies Ultrasonic SS to Blackberrys helped somewhat.
-The Ncores require about 6 hours of warm up to come 'on song' with a solid soundstage. As I acquired the amp to evaluate [directly coupled] balanced and single ended cabling on the fly, I simply leave the its 3pdt center off switchs for switching between inputs in the center muted, Nampon line ungrounded, position.
- Unlike most amplifiers I've evaluated, the Ncore powered by its mating SMPS, does not IMO benefit from added low pass mains filtering. Its SMPS incorporates a CMC filter with X2 and Y2 caps. Regardless of whether Hypex incorporated the filter for emissions purposes, and the input filtering is a happy byproduct, kudos to Hypex. I wouldn't know if the Ncores would benefit from those power conditioners that rely upon the capture, subjugation, and redeployment of Maxwell's Daemons.
- The Ncores came with input signal cable harnesses made of Mogami w2791 cabling. Changing it to my preferred shielded twisted pair cabling was, IMO, a substantial improvement. Current Ncores modules come with cable harnesses labeled "hypex electronics QuietConduit low-noise balanced audio cable". Per Bruno

We did indeed decide to roll our own. It's a full custom product designed by yours truly. The manufacturer is "one of the usual suspects".

If your Ncore has an original Mogami based harness, I'd suggest rolling your own, or trying Hypex's newer implementation.

As an analytic tool, my implementation of the Ncore 400 is quite successful. As part of a system for the joy of listening to music, I'm not quite there, yet.

FWIW, YMMV,
Paul
Kaplan Cable

 

[iansr]

I've had my ncores for about a week now. By way of reference, I'm a SET fan but also really like Nelson Pass' First Watt amps. I have been using a pair of F4 monoblocks for the last couple of years to drive my Quad 989s, one of which needs a new panel and so I'm curretnly using an old pair of 57s. Now I remember all the fuss about the Nuforce amps when they came out but when I eventually heard them I wasn't impressed. So it was with some trepidation that I ordered the ncores purely on the back of all the reviews from very happy owners.

I'll be brief; I agree with Paul in saying that the ncores are a tad "colder", (less romantic?) than a SET or indeed a Class A SS amp like the F4, but the level of clarity, transparency and articulation is just in a different league. And then there is the power. I thought that the F4s (combined with my high voltage output (80v) Leben preamp provided all the power my Quads needed, but I was woefully mistaken. The ncores enable the 57s to produce very respectable bass - they now rock! Can't wait to get the 989s back in the system.

I wouldn't say no to a smidgin more warmth but that's a minor complaint and overall these are not only the best amps I have ever heard, they also represent the best value for money in amps that I've heard. Others have called them game changers. I wouldn't argue.

For the avoidance of doubt, i have no connection with ncore.

 

[MarinJim]

Interesting from P.F.:

" Conclusion

Audiophiles come in many stripes. Attend the next meeting of your local audio society. About the only thing this diverse group has in common is their tight-fisted concern for their billfolds. The MP150s will cut the mustard for a wide swath of those tastes, ranging from the PRAT Flat Earth types, to the precision and control technophiles, to the reluctant tube-ophile, just stopping short of the tone, gotta-have-more-tone, lover of beauty. The amps are dead quiet, without a hint of grain, stridency or other solid-state symptom. They actually sound closer to quality SET amps than to transistors, with a large dollop of fleshy, fulsome images, and a wonderfully integrated treble. In looking over this copy, I realize I didn't stress enough just how musical the little MP150s are. You may have minor quibbles about that voicing—decisions were made biased in favor of musicality, especially in the shaping of their dynamics. Still, if you have a taste for a sweetened sound, with a touch or more of euphony, don't look to the MP150s—you won't find it there—they measure flat as a pancake.

The issues have been addressed. I can vouch that the MP150s are wish fulfillment for owners of Kharma speakers. (I would have loved just a touch darker tonal balance—for my taste, that would have been ideal.) This is the Kharma Ceramique sound fully realized. I'm not sure if you'll ever find a better synergy—certainly not at this price point. Subjectively, based on what I'm hearing, I'd venture the amp has the ideal electrical characteristics for the Kharma CRM 3.2 speakers. It fulfills the speakers' potential. (I had to put qualifiers in this paragraph, because the MP150 is aimed at the Matrix and Ceramique levels, Kharma's lower rungs. An Exquisite level amp will be available soon.)

The Kharma MP150 offered at $6800/pair is a freak occurrence, a rare marketplace anomaly. This is a case of extreme value. Had they been packaged in a larger, fancier chassis, I have no doubt they would have no problem selling at $10,000 or more. I can't think of a competitive solid-state amp at anywhere near this price. The one that comes to mind is the darTZeel NHB-108 with its $18,000 MSRP. The MP150 is better. Marshall Nack"

 

[MarinJim]

I am seriously considering buying some UCoare based amps. How do they compare against the best class A or AB? What I have read, the new breed of class D NCore is up there with the state of the art in amplification. Thoughts?

 

[Elberoth]

Thanks Gary. I should have them by next week. WILCO on the reveiw. I have the BMC monoblocks to compare them against. I believe the BMC monoblocks are top performers, so it should be fun.

Any update ?

 

[dallasjustice]

It didn't go well. The amp worked for a few minutes. I heard one song. The left mono got really hot and started smoking! I sent them back. Thank god for American Express.
Frohe Weinachten!

 

[A.wayne]

 

[arthurs]

I have a pair of the Merrill Audio Veritas coming this week. They're built on the NC1200 platform of the NCore and have a couple positive user reviews out there. I'll put some thoughts up after I get a couple weeks on them.

 

[opus111]

How do they compare against the best class A or AB? What I have read, the new breed of class D NCore is up there with the state of the art in amplification. Thoughts?

From what the guys on here are saying, and what I know of Bruno and the technology, I'd say the ncores will suit those who want bags of power and have S-D DACs. Those who favour multibit DACs will probably find ncore's colder tonality detracts from the experience. Bruno does rather design amps by the THD+N numbers and probably hasn't made measurements of noise modulation - the reports of its colder tonality are telling me that it wouldn't measure so highly in that.

 

[MarinJim]

It didn't go well. The amp worked for a few minutes. I heard one song. The left mono got really hot and started smoking! I sent them back. Thank god for American Express.
Frohe Weinachten!

Und ein gutes neues Jahr!!

 

[A.wayne]

So class-d is still out to sea .....

 

[garylkoh]

So class-d is still out to sea .....

I wouldn't say that.....

 

[Elberoth]

I wouldn't say that.....

Did you have a chance to evaluate the new Ncore modules in your own designs ?

 

[Occam]

So class-d is still out to sea .....

What Gary said....

I've yet to slot in a different power amp that didn't benefit subjectively from some level of 'slap and tickle' on the amp itself or the components feeding it.

Merrill brought over a pair of his eponymous NC1200 monoblocs to compare to my own NC400 build and the wonderful Aksa Lifeforce AB amp. IMO, without a change from the standard input buffers on the nCores, discrete on the NC400 and monolithic on the NC1200, they'll never have that midrange density and warmth that I prefer subjectively. Then again, I've no doubt that someone could implement an instrumentation amp input buffer for the non-buffered version of the NC1200 that would address those issues.

IMO, the NC1200 oem modules are better than the NC400s, with a warmer denser midrange, yet more resolving throughout the spectrum. [I've also heard the Atsah NC 1200s] I did make some changes based upon suggestions from Merrill. Specifically, the change from Superior Electric BP30 binding posts to Cardas nekk'd copper posts was much to my liking.
But the largest change was wrought from tube swaps on the EAR Acute III CD player. The CBS specified Siemens PCC88s worked wonderfully on the inherently warm Aksa amp, but were too cold and sterile feeding the Ncores. After much swapping, the French Dario Miniwatts E188cc are, for me in my system, wonderful.

Futzing about with one's system when you slot in a new component is a given, for me. It may be finding the right tubes, isolation devices, or cables to suit the changes. YMMV

FWIW,
Paul
Kaplan Cable

 

[A.wayne]

Well I'm still waiting for class-d to kill me with it ......

 

[MarinJim]

I am going with Theta's new Prometeus monoblocks. No more overly romantic misty amps for me. To each his own. But whatever system one has, just enjoy!

 

[A.wayne]

I would love to hear them, not oppose to the topology , just the sound , class-d captures the speed of live music very well , it's the damn ringing and lack of bandwidth details that get me ...



"The new amplifier, named Prometheus, is rated at 250 watts RMS full-band into 8 ohms, 500 watts RMS full-band into 4 ohms and 1,000 watts RMS full-band into 2 ohms all with less than 0.01% THD. Signal-to-noise ratio exceeds 128 dB, frequency response is +0, -.5 dB from 20 Hz to 20 kHz at any impedance and damping factor exceeds 2,500 from 0 Hz to 20 kHz."


Love the power numbers it maybe even be able to power the 1 ohm amp widow i have here