Hypex nCore vs Class A amps

[barrows]

The problem is not having the measurement gear and doing measurements on their products. The problem is that some manufacturers allow horribly measuring gear to pass and go on sale. Totaldac for example comes to mind.

Hi Matias! I am not so sure I agree fully here. As mentioned, most manufacturers I am aware of do have measrement gear, know how to use it, and measure all of their products. Such as Pass Labs, for example. Nelson Pass is very forthcoming about his approach, and shares very generously in the DIY community his thoughts on design. His amplifiers are designed to sound a certain way, this is an informed choice he makes. Personally I have no problem with this, and I am fully confident that if Mr. Pass wanted to, he could make an amplifier which measured similar to a Benchmark, that is just not what he does. Where is the "problem" here, I do not see one. Pass makes amps which sound a certain way, and a potential customer can choose to purchase one, or not: no one is forced to purchase his amps. If the customer is happy with their Pass amplifier, and gets enjoyment from listening to it, there is no problem.

Sure, there may be some very small, boutique, high end companies who do not have measurement gear (although they can also send their gear out for measurement), but all the companies I am familiar with do have the gear, in house, and do make the measurements. I am thinking of companies like Sim Audio, Ayre, Chord, PS Audio, Mbl, Constellation, Mola Mola, etc... Just because they do not publish a full suite of measurements is no indication of what or how they measure!

As to TotalDAC, where can I see the measurements? I have always wanted to see measurements of that product!

edit: never mind, found it right here, cool!

 

[Matias]

Hi Matias! I am not so sure I agree fully here. As mentioned, most manufacturers I am aware of do have measrement gear, know how to use it, and measure all of their products. Such as Pass Labs, for example. Nelson Pass is very forthcoming about his approach, and shares very generously in the DIY community his thoughts on design. His amplifiers are designed to sound a certain way, this is an informed choice he makes. Personally I have no problem with this, and I am fully confident that if Mr. Pass wanted to, he could make an amplifier which measured similar to a Benchmark, that is just not what he does. Where is the "problem" here, I do not see one. Pass makes amps which sound a certain way, and a potential customer can choose to purchase one, or not: no one is forced to purchase his amps. If the customer is happy with their Pass amplifier, and gets enjoyment from listening to it, there is no problem.

Sure, there may be some very small, boutique, high end companies who do not have measurement gear (although they can also send their gear out for measurement), but all the companies I am familiar with do have the gear, in house, and do make the measurements. I am thinking of companies like Sim Audio, Ayre, Chord, PS Audio, Mbl, Constellation, Mola Mola, etc... Just because they do not publish a full suite of measurements is no indication of what or how they measure!

As to TotalDAC, where can I see the measurements? I have always wanted to see measurements of that product!

Yes, I agree with you: some designers just choose not to reduce distortion as much as they can, and opt instead to "tune distortions to taste". Valves and vinyl comes to mind too.

Here is the totaldac measurements. I am sure the designer has all the gear he needs and still chose to let this product sell. To each his own, I guess, but ASR is demonstrating this choise very clearly.
https://www.audiosciencereview.com/...and-measurements-of-totaldac-d1-six-dac.8192/

 

[barrows]

Yes, I agree with you: some designers just choose not to reduce distortion as much as they can, and opt instead to "tune distortions to taste". Valves and vinyl comes to mind too.

Yes, agreed. I do not see this as a "problem", as no one is forced to purchase any piece of audio gear. Design engineers make their choices, and audiophiles make theirs, it is all good.

 

[Darkweb]

The nuanced approach is a breath of fresh air Barrows, great posts!

 

[mocenigo]

2. Having listened to many, many amplifiers, and many systems throughout my 20 years in the industry and being an audiophile since high school (with an audiophile Uncle and Father), I have learned, mostly, how to avoid allowing things like aesthetics to color my view of sound quality

Oh, I was referring to our Purifi builds. The more beautiful you make it, the better it will sound. It was a bit tongue-in-cheel and a stab at us DIYers

 

[mocenigo]

As to the example I posted here, one might be interested in comparing the 10 kHz square wave response of an NC-400 amplifier vs. that of the Bricasti M28 mono blocks (available at stereophile.com). This is one measure where well engineered class A/B amplifiers consistently outperform their Class D counterparts. Perhaps this has something to do with some differences heard during listening comparisons (this is only speculation on my part though, I have not specifically been able to correlate these two things). Of course tube amplifiers tend to do the worst on a 10K square wave, likely due to problems caused by the output transformer.

Of all tests, this may well be one of the less relevant to SQ, since already the second harmonic is inaudible (unless one believes to be capable of hearing 20Khz). Class D designs have a smaller bandwidth than many AB amps - this explains many apparently crappy 10Khz square waves.

 

[barrows]

Of all tests, this may well be one of the less relevant to SQ, since already the second harmonic is inaudible (unless one believes to be capable of hearing 20Khz). Class D designs have a smaller bandwidth than many AB amps - this explains many apparently crappy 10Khz square waves.

I agree, mostly. But I am not entirely certain about how the ear/brain perceives the onset and decay of the waveform. I would need to consult a person with cutting edge expertise in psychoacoustics to fully understand this. I do, though, understand the frequency make up of square waves.

 

[Julf]

I agree, mostly. But I am not entirely certain about how the ear/brain perceives the onset and decay of the waveform. I would need to consult a person with cutting edge expertise in psychoacoustics to fully understand this. I do, though, understand the frequency make up of square waves.

If the ear doesn't have receptors for frequencies above 20 kHz, it also can't hear components of the onset or decay that would be above 20 kHz.

 

[barrows]

Oh, I was referring to our Purifi builds. The more beautiful you make it, the better it will sound. It was a bit tongue-in-cheel and a stab at us DIYers

Yeah, I kind of figured that. But there is something to getting a build boxed up, solid, with optimized wiring paths, and properly mounted in and output jacks, with some degree of vibration control (vs. mounted on a board with wires all over the place), which often contributes to actual sound quality.

 

[barrows]

If the ear doesn't have receptors for frequencies above 20 kHz, it also can't hear components of the onset or decay that would be above 20 kHz.

Hi Julf, are you up to date with the latest psychoacoustic research into this? The reason I ask is because I thought I recalled reading something new about this topic, related to recent psychoacoustic research using brain scans, but I cannot recall it completely.

 

[Julf]

Hi Julf, are you up to date with the latest psychoacoustic research into this? The reason I ask is because I thought I recalled reading something new about this topic, related to recent psychoacoustic research using brain scans, but I cannot recall it completely.

Would love to see a link - the only ones that I can think of are the old and discredited Oohashi and Kunchur ones.

 

[barrows]

Would love to see a link - the only ones that I can think of are the old and discredited Oohashi and Kunchur ones.

Yeah, sorry, it is a vague memory!

 

[mocenigo]

Yeah, I kind of figured that. But there is something to getting a build boxed up, solid, with optimized wiring paths, and properly mounted in and output jacks, with some degree of vibration control (vs. mounted on a board with wires all over the place), which often contributes to actual sound quality.

This is absolutely true. I mounted the whole amp on a suspended inner baseplate, instead of feet I have four 5x5x1cm squares of sorbothane affixed to the case with 3M adhesive tape and some (mostly aesthetic) cork on the bottom. I have optimised the placement of components (kept all AC to the very left, all power supplies, whether linear or switching, output their DC to their right, i.e. the vertical center line of the amp, and all the audio circuitry is at the right) and somewhat the wiring as well: For instance, the 10cm or so of cabling from the purifi module out to the speaker terminals have been made with a "star quad" of 1.5mm2 Somer Cable Orbit cores - nothing esoteric, just good copper in a proven, good geometry, giving 3mm2 of cross section per pole, which is absolutely fine. Maybe all of this does nothing... but it gives me peace of mind, knowing that everything is in order and following sane best practices (as opposed to both sloppiness and snake oil addiction).

 

[Rich W]

This is absolutely true. I mounted the whole amp on a suspended inner baseplate, instead of feet I have four 5x5x1cm squares of sorbothane affixed to the case with 3M adhesive tape and some (mostly aesthetic) cork on the bottom. I have optimised the placement of components (kept all AC to the very left, all power supplies, whether linear or switching, output their DC to their right, i.e. the vertical center line of the amp, and all the audio circuitry is at the right) and somewhat the wiring as well: For instance, the 10cm or so of cabling from the purifi module out to the speaker terminals have been made with a "star quad" of 1.5mm2 Somer Cable Orbit cores - nothing esoteric, just good copper in a proven, good geometry, giving 3mm2 of cross section per pole, which is absolutely fine. Maybe all of this does nothing... but it gives me peace of mind, knowing that everything is in order and following sane best practices (as opposed to both sloppiness and snake oil addiction).

When will you send it in to Amir to verify the performance of all of these additions?

 

[mocenigo]

When will you send it in to Amir to verify the performance of all of these additions?

I wish I could do that easily, but I live in the EU and Amir lives in the US. All of this would take a lot of time and would also be expensive. As I said above, maybe this just gives me only piece of mind but:
1) No esoteric case feet - just four little squares of sorbothane that cost me 15 EUR total. I need some kind of feet under the case anyway, right?
2) No thick steel or mumetal walls or transformer cans, no case CNC machined from a single block of aluminum.
3) No snake oil cable, just inexpensive but good purity copper cable used in a geometry that is known to help reject IEM/RFI
I did not claim anything about the performance of these additions. It is just sane engineering practices and as for the feet, well, not a big expense - I did not buy the sorbothane from the-high-end-snake-oil-seller-dot-com, but from a generic supplier.

Hence, I am quite confident that I have not made the Neurochrome UB + Purifi 1ET400A modules worse than what we should expect. Because of the quality of the Neurochrome UB the SINAD, for instance, should be between 104 and 108DB at 5W (and looking at the SINAD of the UB, even if reduced by the 1ET400A gain, everything should be closer to 108 than 104).

 

[Rich W]

I wish I could do that easily, but I live in the EU and Amir lives in the US. All of this would take a lot of time and would also be expensive. As I said above, maybe this just gives me only piece of mind but:
1) No esoteric case feet - just four little squares of sorbothane that cost me 15 EUR total. I need some kind of feet under the case anyway, right?
2) No thick steel or mumetal walls or transformer cans, no case CNC machined from a single block of aluminum.
3) No snake oil cable, just inexpensive but good purity copper cable used in a geometry that is known to help reject IEM/RFI
I did not claim anything about the performance of these additions. It is just sane engineering practices and as for the feet, well, not a big expense - I did not buy the sorbothane from the-high-end-snake-oil-seller-dot-com, but from a generic supplier.

Hence, I am quite confident that I have not made the Neurochrome UB + Purifi 1ET400A modules worse than what we should expect. Because of the quality of the Neurochrome UB the SINAD, for instance, should be between 104 and 108DB at 5W (and looking at the SINAD of the UB, even if reduced by the 1ET400A gain, everything should be closer to 108 than 104).

Sounds like a lot of hot air and no substance. I'm betting it measures worse than a bone stock un-modded eval board powered by the Hypex SMPS1200A400 supply. Not sure why a novice would mess with the work of professionals unless they had the means to verify performance.

 

[mocenigo]

Sounds like a lot of hot air and no substance. I'm betting it measures worse than a bone stock un-modded eval board powered by the Hypex SMPS1200A400 supply. Not sure why a novice would mess with the work of professionals unless they had the means to verify performance.

Hello, Mike.

 

[Rich W]

Hello, Mike.

Who's Mike?

 

[DonH56]

I wish I could do that easily, but I live in the EU and Amir lives in the US. All of this would take a lot of time and would also be expensive. As I said above, maybe this just gives me only piece of mind but:
1) No esoteric case feet - just four little squares of sorbothane that cost me 15 EUR total. I need some kind of feet under the case anyway, right?
2) No thick steel or mumetal walls or transformer cans, no case CNC machined from a single block of aluminum.
3) No snake oil cable, just inexpensive but good purity copper cable used in a geometry that is known to help reject IEM/RFI
I did not claim anything about the performance of these additions. It is just sane engineering practices and as for the feet, well, not a big expense - I did not buy the sorbothane from the-high-end-snake-oil-seller-dot-com, but from a generic supplier.

Hence, I am quite confident that I have not made the Neurochrome UB + Purifi 1ET400A modules worse than what we should expect. Because of the quality of the Neurochrome UB the SINAD, for instance, should be between 104 and 108DB at 5W (and looking at the SINAD of the UB, even if reduced by the 1ET400A gain, everything should be closer to 108 than 104).

Sounds like reasonable best-practices for assembly and dress, not sure what's so bad about it?

 

[Rich W]

Sounds like reasonable best-practices for assembly and dress, not sure what's so bad about it?

I was under the impression this was a science orientated forum. And when people make expensive modifications to existing products in which the performance has been verified, evidence is provided to support the improvements. But perhaps I was mistaken.