I guess there is no-one stopping you...
I have to say I would be pretty surprised. What are you basing your view on?
I guess there is no-one stopping you...
I have to say I would be pretty surprised. What are you basing your view on?
Thanks, but I have more important things to do, and class d is not on my wishlist
SMPS is working at high frequencies and might intermodulate with HF audio.
Problem is that specifications are good, but maybe there is more at stake.
Sometimes a trial/error approach can help solving problems, and replacing a SMPS with a linear supply might be an opportunity.
After all, raising quality of audio equipment over time has been more a trial/error thing than the outcome of a purely scientific approach, and besides the subjective factor remains to be dominant
Class D is working at high frequencies, and might intermodulate with HF audio... now, wait....
Sure. But properly twisting and protecting the wiring might be an easier first step.
Not sure Bruno would agree with that.
I guess ti33er already tried to optimize his build?
Not sure Bruno would agree with that.
Do we have to agree with Bruno before taking a breath....?
Not sure Bruno would agree with that.
I recall Bruno writing early in this thread that SMPS was superior to linear supplies, based on measurements and listening tests. Hypex discontinued their linear supplies years ago.
Do we have to agree with Bruno before taking a breath....?
A subjective or objective breath?
Just find it slightly ironic to talk about trial and error in a thread about an amp that exists purely because Bruno actually took the scientific approach and developed the maths instead of resorting to mere trial-and-error tweaking.
Hi Julf
Nobody local that I know of has an Osciliscope, unfortunately...I would love to have this tested :-(
Safe to say that SGK (many thanks again) already re-built most of my nCore, twisting all the wires properly and patching up other bits he could see were poorly finished...but it still has the same, or similar sonic signature.
Reason I was goading a response as to what this interference/noise from untwisted wires sounds like, is trying to understand if this could be some form of noise affecting my nCore?
It has been said the AUDIOLAB MDAC sounds better outside of its aluminium case (sounds harsher/colder the closer they lower the mainboard to the casing) - the Designer himself stated there may be some RFI refelctions, affecting some circuits? Guess one day I need to find the time and space to run this amp naked, outside of the box.
Other Amps I've tried it against so far are SGK's KRELL 200W (didnt have long to listen but my initial thought was it sounded brasher vs his KRELL), TAG McLaren 60P (60w), 100X5R (100w Monblocks), 250MR (250w Monoblocks) and an ARCAM Stereo 80w. Various 'DACs' and Speakers in these setups also.
It's a similar observation each time so far - my nCore brings out the brashest, most unpleasant sounding high frequencies.
I did a week's swap with my friend who has the TAG McLaren F1 Speakers, for his TAG 250MR ...funny enough I started enjoying my music again, which became less fatiguing and there was just more depth to the sound-stage...no other way to describe it.
Ricky was also happy to have his 250MRs back again as his comments regarding my nCore were ... "Great Bass, but the rest sounds like toast, with no butter" (quite an accurate analogy if I may say so)
Has anyone else noticed similar to what I am describing? ...I was very keen to visit SebbyP to listen on his Phison DAC but he has gone a bit quiet - no offence intended if you are busy Sebby, just seem to have lost contact..cest la vie
Nobody local that I know of has an Osciliscope, unfortunately...I would love to have this tested :-(
Safe to say that SGK (many thanks again) already re-built most of my nCore, twisting all the wires properly and patching up other bits he could see were poorly finished...but it still has the same, or similar sonic signature.
Reason I was goading a response as to what this interference/noise from untwisted wires sounds like, is trying to understand if this could be some form of noise affecting my nCore?
It has been said the AUDIOLAB MDAC sounds better outside of its aluminium case (sounds harsher/colder the closer they lower the mainboard to the casing) - the Designer himself stated there may be some RFI refelctions, affecting some circuits? Guess one day I need to find the time and space to run this amp naked, outside of the box.
Other Amps I've tried it against so far are SGK's KRELL 200W (didnt have long to listen but my initial thought was it sounded brasher vs his KRELL), TAG McLaren 60P (60w), 100X5R (100w Monblocks), 250MR (250w Monoblocks) and an ARCAM Stereo 80w. Various 'DACs' and Speakers in these setups also.
It's a similar observation each time so far - my nCore brings out the brashest, most unpleasant sounding high frequencies.
I did a week's swap with my friend who has the TAG McLaren F1 Speakers, for his TAG 250MR ...funny enough I started enjoying my music again, which became less fatiguing and there was just more depth to the sound-stage...no other way to describe it.
Ricky was also happy to have his 250MRs back again as his comments regarding my nCore were ... "Great Bass, but the rest sounds like toast, with no butter" (quite an accurate analogy if I may say so)
Has anyone else noticed similar to what I am describing? ...I was very keen to visit SebbyP to listen on his Phison DAC but he has gone a bit quiet - no offence intended if you are busy Sebby, just seem to have lost contact..cest la vie
A subjective or objective breath?
Just find it slightly ironic to talk about trial and error in a thread about an amp that exists purely because Bruno actually took the scientific approach and developed the maths instead of resorting to mere trial-and-error tweaking.
I am pretty sure that Bruno, like any EE, does not rule out the empirical, trial/error approach, as a worthwile complementary element in his work. It's not or-or, but and-and. Perfectly normal in scientific thinking, and audio engineering is no exception
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I am pretty sure that Bruno, like any EE, does not rule out the empirical, trial/error approach, as a worthwile complementary element in his work. It's not or-or, but and-and. Perfectly normal in scientific thinking, and audio engineering is no exception
I totally agree. You might have noticed I wrote "Bruno took the scientific approach and developed the maths instead of resorting to mere trial-and-error tweaking" (emphasis added).
I was responding to:
Which of course is correct in that most audio "engineering" (especially "high-end") tends to be tweaking (calling it "empirical" actually assumes it is evidence-based - an assumption that unfortunately often is misplaced), but the real improvements have come from the scientific approach.
Where are you based? No hackerspaces or makerspaces in your area? Ham radio clubs?
Then I would tend to suspect that the issue isn't noise. I assume both channels sound the same?
It would be more of an issue with a DAC that has a bunch of high-speed digital circuits.
That does sound strange, and indeed like there is something wrong with your amp - but pretty hard to figure out what.
Where are you based? No hackerspaces or makerspaces in your area? Ham radio clubs?
Then I would tend to suspect that the issue isn't noise. I assume both channels sound the same?
It would be more of an issue with a DAC that has a bunch of high-speed digital circuits.
That does sound strange, and indeed like there is something wrong with your amp - but pretty hard to figure out what.
I'm in West London; does anyone know (or anyone belong that is reading here) to one of these Clubs, near W4 post code?
I'm still weary of the Aluminium Case reflecting some RFI as a lot more current goes through these Amps than a DAC, right?
...if a simple untwisted wire/s can cause this noise, what else may do this - there is a lot of heat and electric activity going on inside these cases and if the nCore is sensitive...Thanks
Did you check local wall voltage?
I know that in London wall voltage can exceed 250V, which can saturate standard toroidal power supply transformers (in case of linear supply).
SMPS600 is rated up to 264V when I am right and I don't know if it is sensible to high and/or over voltage but nevertheless it seems good to check.
I know that in London wall voltage can exceed 250V, which can saturate standard toroidal power supply transformers (in case of linear supply).
SMPS600 is rated up to 264V when I am right and I don't know if it is sensible to high and/or over voltage but nevertheless it seems good to check.
The nearest hackerspace seems to be Richmond Makerlabs in Ham (TW10 7NY), and they list a Rigol DS1054Z 4 channel 50MHz Digital Oscilloscope on their equipment list.
Most people have their amps in metal cases, and have no issues. Just to be clear - untwisted wires don't cause noise, they just don't attenuate noise as well as properly twisted ones, and the nCores aren't especially sensitive. Heat would not cause the kinds of issues you describe.I'm still weary of the Aluminium Case reflecting some RFI as a lot more current goes through these Amps than a DAC, right?
Bruno more than once pointed out the importance of wiring layout, which is more critical in a high feedback amplifier design, and even more in a class d amplifier.
Ncore is a (very) high feedback design, so I can imagine that pcb layout and wiring is critical making it more sensitive than more classical designs.
I was told long ago that the major challenge in class d amplifiers to sound good is pcb layout.
Thanks Gents
So I had one of those PowerInspired AG500 Regenerators and my mains Voltage used to hover around 239-242V ...I did test my 60P amp through it once, at low to medium volumes but as described by others, dynamics sufferered (the Choke theory) ...one day it just stopped working, a week after the Warranty expired...lol - it's under my bed if anyone wants it
Thanks for the link in Ham; may be in contact with them ...also still not been able to compare my nc500 with an nc400 if anyone lives close by W4 Chiswick?
So I had one of those PowerInspired AG500 Regenerators and my mains Voltage used to hover around 239-242V ...I did test my 60P amp through it once, at low to medium volumes but as described by others, dynamics sufferered (the Choke theory)
...one day it just stopped working, a week after the Warranty expired...lol - it's under my bed if anyone wants itThanks for the link in Ham; may be in contact with them ...also still not been able to compare my nc500 with an nc400 if anyone lives close by W4 Chiswick?
I just finished reading every page of this thread. I learned quite a bit, and some of it was even related to Ncore.
Julf, Hypex should send you another 8 channels of NC400 for free considering how long you have been in here helping people and providing technical support.
When you read 11,000 posts over a two week period, some patterns become really obvious.
One thing that became very predictable, very early, was pieter t showing up regularly to snipe at Hypex, or class d in general, or switching power supplies in general. I don't understand what motivates someone to monitor a thread related to something they don't own, and don't plan to ever own, for years, so they can mostly just make negative comments.
Pieter t, I don't mean to attack you personally, and I won't mention it again, but it really stands out when reading through years of posts start to finish. You did post some helpful stuff along the way but there is always a negative undertone to your participation in the thread. Do you sell products that compete with Hypex?
Anyway, I'm happy this morning. I submitted my Hypex order Saturday afternoon and woke up this morning to find a shipping notice. Should have my stuff later this week. Now I have to get my new speakers built but that's going to take a couple months.
-Chris
Julf, Hypex should send you another 8 channels of NC400 for free considering how long you have been in here helping people and providing technical support.
When you read 11,000 posts over a two week period, some patterns become really obvious.
One thing that became very predictable, very early, was pieter t showing up regularly to snipe at Hypex, or class d in general, or switching power supplies in general. I don't understand what motivates someone to monitor a thread related to something they don't own, and don't plan to ever own, for years, so they can mostly just make negative comments.
Pieter t, I don't mean to attack you personally, and I won't mention it again, but it really stands out when reading through years of posts start to finish. You did post some helpful stuff along the way but there is always a negative undertone to your participation in the thread. Do you sell products that compete with Hypex?
Anyway, I'm happy this morning. I submitted my Hypex order Saturday afternoon and woke up this morning to find a shipping notice. Should have my stuff later this week. Now I have to get my new speakers built but that's going to take a couple months.
-Chris
When there is a negative undertone in my participation, well that is not on purpose.
What I have experienced however is that it is extremely difficult to have a critical attitude on a forum when people are "into" something particular, and tunnel vision is easily lurking around the corner when people are enthusiastic. Then when coming up with some critics people find it difficult to accept (it kind of disturbs their dream...).
Exactly four years ago I came up with the idea to compare different types of power supplies, and it was merely received as an attempt to undermine the integrity of Hypex and their amps
.My experience with Hypex is that I built some UCD module based amplifiers in the past (nothing special wrt sound quality); further experience with class d is with Philips TDA8920/50 (another "Dutch" class d technology based on UCD). Hypex is physically next to my doorstep; I met the people sometimes and there are no problems whatsoever
; I admire what they have achieved with class d technology, especially Ncore. The fact that I am into another part of audio technology has nothing to do with it.In general I have nothing against class d as I am a music lover in the first place, and in the end I don't give a damn how the reproduction takes place as long as I enjoy.
My participation here is because I consider class d technology as one of the more interesting developments in audio over the last years, and I am interested in these developments.
Being critical however should not be judged as a threat but more as an attempt to keep eyes and ears open
.PCB layout is pretty critical, but the wiring issues are the same as with any high feedback design.
I would say that feedback topology is the primary factor, but a bad pcb layout can of course spoil an otherwise good amp.
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