Ncore Improvements

serengetiplains · « **Reply #220 on:** 24 Jul 2012, 01:56 am »

Another insult.

What I'm doing here is groping for a rationale for something I hear and have often heard, and in a way I personally find technically plausible. If you have technical objections, I'm open to hearing them. Even Bruno said he can't rule out those caps doing something at audio frequencies. Because DA is a lower-frequency distortion (lower than the original voltage charge that incited the DA response), bypassing DA-rich electrolytics would seem a likely candidate for improving performance in that respect.

cab · « **Reply #221 on:** 24 Jul 2012, 01:58 am »

Not an insult at all....It would simply seem that the technical nature of your posts above would find a more relevant audience on a more technically oriented forum.

So you are trying to lower distortion? At what level is it below the audible threshold?

serengetiplains · « **Reply #222 on:** 24 Jul 2012, 02:12 am »

Quote from: cab on 24 Jul 2012, 01:58 am

So you are trying to lower distortion? At what level is it below the audible threshold?

Yes.

For sure at zero distortion.

cab · « **Reply #223 on:** 24 Jul 2012, 02:19 am »

If you don't know at what level you can hear distortion, how do you know if a lowering of distortion is audible? How can you be certain that what you hear isn't simply a more preferred distortion?

Since the distortion of the stock ncore is undoubtedly already lower than everything else in your playback chain, wouldn't it be a more plausible pursuit to try and lower the distortion in the components that have distortion that is factors greater than in the ncore?

hifial · « **Reply #224 on:** 24 Jul 2012, 02:41 am »

serengetiplains · « **Reply #225 on:** 24 Jul 2012, 05:04 am »

You might ask when distortion measurement is at the limit of what in the audible world it can measure. That's the real question, isn't it? How else can one explain the improvement of our measuring abilities? On that note, I think Bruno thinks his next amp will be better. I'm interested in the question of how that is possible.

I'm one of those guys who doesn't buy that measurements explain more than just a part of what is audibly relevant. And as far as they go, the measurements are good. We fundamentally want an amplifier with zero distortion. Measurements give us an insight into what we then in the language of those measurements can describe as an audibly relevant factor. But there is much more going on in the audio field---I'll call it a field, comprised of inner and outer processes---than measurements can measure.

Let me get a little subtle here. Measurements are a means of particularizing. They say and point to this. But what they miss in particularizing---particular being limited, by definition---what they miss in defining and limiting is the relation between the thus-called defined, limited parts (measurements). And because music is one wave, that relation is a relation as of a whole. Only ever one wave---unity, whole. Measurements only ever approximate in the direction of the whole, which is why things improve.

Put it this way. We have, among many others, THD measurements and IMD measurements. What measurement gives us how those two relate? Do you see the problem there? If you have the measurement that tells you how those two relate, you have a more powerful measurement than either THD or IMD, in which case you'll be using neither in favour of the more powerful measurement. Quantum physicists don't resort to Newtonian equations to do what quantum physicists do as quantum physics. And nuclear be much more powerful than grind-and-bump force.

People get a feel for music, that it's off in this or that way. What is that feeling? It must be an intuited sense of a difference between real and not. We listen to real sounds all day every day. We know what real is. But because it's real, we can't define it---there's nothing to which to compare it! And by extension, it thus is impossible to precisely characterize how something is not real. Why? Because the comparator can't be said. Measurements truly are limited.

Gödel in a nutshell.

OzarkTom · « **Reply #226 on:** 24 Jul 2012, 11:19 am »

Paul McGowan wrote similar comments today in his daily letter.

http://www.pstracks.com/pauls-posts/close-perfection/7526/

serengetiplains · « **Reply #227 on:** 24 Jul 2012, 05:12 pm »

Indeed, my stereo doesn't sound like real sound in all those ways it doesn't. We improve (compare 24/192 to that heard by the master's cringing dog) by trying something new, and the new can only be measured when implemented. But where does the new come from? It comes from intuition. Bruno tried something new, and yes, what he implemented lowers distortion, but he had to grok some assumption somewhere that allowed seeing more deeply into processes to allow advance to occur. Measurement, per Gödel, is always but an aid to perceiving more deeply into fixed assumptions that need to be overturned. The best way to forestall that process is to assume there's nothing new under the sun ...

Occam · « **Reply #228 on:** 24 Jul 2012, 09:15 pm »

Do that google thang on 'Timothy C. Neugebauer inductance cancellation'

serengetiplains · « **Reply #229 on:** 24 Jul 2012, 11:47 pm »

Ha ha. Gödel, what a treasure he left us. All our sets (our theories, our measurement regimes, our mathematizations) exist as a box. Each axiom in a set refers to, gains meaning from, assumptions on which it is based, which implies this: to create a larger, more capable set (or understanding etc), one has to question assumptions, which are tacit, invisible, the water in which one swims. In other words, any advance arises from thinking creatively, outside the box.

Thanks for the Neugebauer link. I had a similar idea a few years ago to this in one of N's papers, and wondered how the compensation winding could be used in an active voltage regulator:

cab · « **Reply #230 on:** 25 Jul 2012, 01:05 pm »

Quote from: serengetiplains on 24 Jul 2012, 05:04 am

You might ask when distortion measurement is at the limit of what in the audible world it can measure. That's the real question, isn't it? How else can one explain the improvement of our measuring abilities? On that note, I think Bruno thinks his next amp will be better. I'm interested in the question of how that is possible.

I'm one of those guys who doesn't buy that measurements explain more than just a part of what is audibly relevant. And as far as they go, the measurements are good. We fundamentally want an amplifier with zero distortion. Measurements give us an insight into what we then in the language of those measurements can describe as an audibly relevant factor. But there is much more going on in the audio field---I'll call it a field, comprised of inner and outer processes---than measurements can measure.

Let me get a little subtle here. Measurements are a means of particularizing. They say and point to this. But what they miss in particularizing---particular being limited, by definition---what they miss in defining and limiting is the relation between the thus-called defined, limited parts (measurements). And because music is one wave, that relation is a relation as of a whole. Only ever one wave---unity, whole. Measurements only ever approximate in the direction of the whole, which is why things improve.

Put it this way. We have, among many others, THD measurements and IMD measurements. What measurement gives us how those two relate? Do you see the problem there? If you have the measurement that tells you how those two relate, you have a more powerful measurement than either THD or IMD, in which case you'll be using neither in favour of the more powerful measurement. Quantum physicists don't resort to Newtonian equations to do what quantum physicists do as quantum physics. And nuclear be much more powerful than grind-and-bump force.

People get a feel for music, that it's off in this or that way. What is that feeling? It must be an intuited sense of a difference between real and not. We listen to real sounds all day every day. We know what real is. But because it's real, we can't define it---there's nothing to which to compare it! And by extension, it thus is impossible to precisely characterize how something is not real. Why? Because the comparator can't be said. Measurements truly are limited.

Gödel in a nutshell.

Nice but if you can't or don't measure something you have no way to know if it is really an improvement or simply a difference.

And none of this addresses the issue of the weak(er) links in the chain. Why spend the time on the strongest link? That makes no sense......

Barry_NJ · « **Reply #231 on:** 25 Jul 2012, 07:47 pm »

Quote from: cab on 25 Jul 2012, 01:05 pm

And none of this addresses the issue of the weak(er) links in the chain. Why spend the time on the strongest link? That makes no sense......

Will hearing aids improve our reception/perception?

OzarkTom · « **Reply #232 on:** 25 Jul 2012, 11:08 pm »

I am afraid that improving the weakest link (the recording) in our systems is completely out of our hands. The recording engineers still believes that Monster Cable is state-of-the-art.

serengetiplains · « **Reply #233 on:** 26 Jul 2012, 12:33 am »

That's my view also, Tom. And up the chain from there, the next most-important link is the digital signal whose distortions are amplified by the rest of the chain.

serengetiplains · « **Reply #234 on:** 4 Aug 2012, 02:53 am »

Here's a picture of the innards of the Octave preamp. Notice the cascade of film capacitors bypassing power-supply capacitors in the psu on the left and in what looks to be the power supply section in the main chassis (upper left).

serengetiplains · « **Reply #235 on:** 19 Aug 2012, 07:53 pm »

And here's the Soulution 720 preamp. Notice the film bypasses.

serengetiplains · « **Reply #236 on:** 19 Aug 2012, 07:55 pm »

Question: why not use cheaper electrolytic bypasses? Less inductance with electrolytics, yes?

James Romeyn · « **Reply #237 on:** 11 Sep 2012, 05:14 pm »

I want to hear NC1200 and/or bridged NC400 because of my personal experience with NC400MB (mono blocks). Speakers are my Ambiance/Mode Cancelling array, two stand mount monitors per channel (each monitor 5.3 Ohm minimum), wired either parallel (2.65 Ohm minimum) or series (10.6 Ohm minimum). A thread in the Speaker "Enclosure" circle has diagram and description. True sensitivity is 88 dB/2.83V/1M, 3000cf room, three channel Trinaural System, mains active crossed 2nd order @ 80 Hz.

NC400MB sound quality is so much better (in every parameter) driving the latter load that I have no interest in hearing it drive the former load. This is a surprise and disappointment because the first reason to build mono blocks was 4x higher voltage potential driving the former load (the second reason was shortest possible speaker cables).

Driving 10.6 Ohm minimum load impedance, I presume NC400 maximum voltage swing is identical whether an SMPS600 drives one or two NC400. To what extent do readers agree/disagree? If correct, then the only purpose served by one of my SMPS600 is 6' shorter speaker cables.

In this room maximum SPL is just below live. Hence my desire to hear NC1200 and/or bridged NC400. Other than that, I'm a happy camper and never heard any amp I like better.

It seems critical to confirm the speaker's minimum load impedance before judging NC400 performance. If NC400 luminescence and tonal density falls short of your favorite tubes, insure you audition a speaker with minimum impedance magnitude close to 6 Ohms before making a final judgement.

At that point, you can decide if NC400 performance justifies different speakers or if NC1200 or bridged NC400 are the best compromise.

Which OEM plan live NC1200 demo @ CES?

cab · « **Reply #238 on:** 11 Sep 2012, 09:21 pm »

It is interesting that you should find the performance difference so great between the two speaker loads; one of the main design goals and performance targets as expressed many times by Bruno is the load independent response of the ncore. Looking at the frequency response at different loads confirms this. It might be beneficial to ask Hypex about this.....

James Romeyn · « **Reply #239 on:** 11 Sep 2012, 09:50 pm »

Quote from: cab on 11 Sep 2012, 09:21 pm

It is interesting that you should find the performance difference so great between the two speaker loads; one of the main design goals and performance targets as expressed many times by Bruno is the load independent response of the ncore.

I agree entirely, hence my "surprise and disappointment." The lower sound quality (higher and/or more distasteful distortion content) commensurate with the lower impedance prevents me from enjoying 4x larger voltage envelope.

Quote

Looking at the frequency response at different loads confirms this. It might be beneficial to ask Hypex about this.....

What about distortion content 2.65 Ohms vs. 10.6 Ohms?

I think I will contact Jan-Peter or Bruno, but only after I confirm the actual minimum load impedance, which might possibly (though doubtful) be less than 5.3 Ohms @ 200 Hz (flat 4 Ohms above 600 Hz) per monitor (2.65 Ohms with two monitors in parallel). There's no known reason to disbelieve the OEM impedance graph by the original speaker designer.

Till then, an appropriate question to Hypex might be:

With levels matched (series +6dB, parallel -6dB), within NC400 maximum current and voltage envelope, how do you quantify expected maximum quality difference between the two loads described above (identical except for minimum impedance)?