An unshakable preference for Harman products? The mischievous could have much fun cross correlating manufacturer, panther rating and speaker spinorama results. On balance though he does a lot of value demonstrating that legacy and established 'non woo' audio companies can be as cynical and corner cutting as anyone.
Do a simple pulse test at different frequencies with a scope.
Compare different wires. See how the rising and falling signals are distorted.
One condition, they must be adequately rated for your equipment.
If it does not satisfy you, use a THD analyzer.
Then get this bee out of your bonnet, so that another can enter and divert your mind to a new entertaining thought.
Compare different wires. See how the rising and falling signals are distorted.
One condition, they must be adequately rated for your equipment.
If it does not satisfy you, use a THD analyzer.
Then get this bee out of your bonnet, so that another can enter and divert your mind to a new entertaining thought.
Measuring for audibility in such a simple way does not always make problems show up well. There are different types of tests for different purposes.
For example, one (non-wire related) audible problem that was NOT found with pulse or THD tests is the following: https://tinyurl.com/49mfa7tm ...The problem was initially detected by human hearing. A subsequent investigation found out how to measure the cause. After that, a design fix was developed.
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Bruno and Lars talked about it in some interviews. They reported that they received a few customer complaints. In one interview they said Lars heard it too and told Bruno it sounded a lot like hysteresis distortion he found in speaker drivers. BTW, we have been through all this before. Links were provided to the interviews.
Seems like Bruno didn't expect it to be audible in his output inductor. Probably the reason those guys talk about it at all is because they have a fix for it and they don't think their competitors do.
Not in this form, at least in the audio realm. This appears to be a novel discovery and most interestingly of a not steady of state phenomena typically amenable to the standard implementations of Fourier analysis.
https://purifi-audio.com/wp-content/uploads/2020/04/hd3loop.mp4?_=2
Ever heard about magnetic amplifiers? They were widely used in the military, since they are "solid state", have virtually no ambient temperature limitations, and an acceptable resilience to EMPs. Hysteresis distortions were well studied in this context. Granted, not an audio application.
Still cannot find any details about "initially detected by human hearing". I would think (if the interview is not a marketing ploy, no audio operation today can avoid going there, usually by trying to identify differentiators) it was more like a missing design target rather than a new effect, identified "by the ear".
Still cannot find any details about "initially detected by human hearing". I would think (if the interview is not a marketing ploy, no audio operation today can avoid going there, usually by trying to identify differentiators) it was more like a missing design target rather than a new effect, identified "by the ear".
There was some discussion a while back starting around: https://www.diyaudio.com/community/threads/the-black-hole.349926/post-6715378 ...post #7194. Jan Didden chimed in a few posts later to the effect Bruno told Jan he was looking for something.
One of the interviews is at: https://audiophilestyle.com/ca/bits...eaders-qa-with-lars-risbo-bruno-putzeys-r815/ ...Also IIRC, the interview where they talked about Lars hearing it was a recorded audio interview. Seems to me there were maybe a total of three interviews that talked about the subject, but Lars hearing it was only in one interview.
Regarding discovery of the problem by human hearing, I was referring to the story Bruno and Lars told about finding a problem in their amplifier. Seems like they were talking about discovery of a problem in class D amplifiers, perhaps like Doug Self keeps describing new distortion sources in amplifiers. Maybe similar type of thing for Cherry. IIUC nobody is claiming discovery of a new physical phenomenon or anything like that.
EDIT: Another interview where it says: "Putzeys’ research of this phenomena was motivated by sporadic reports of a sort of 'granularity' in the sound reproduction with class D amplifiers."https://audioxpress.com/news/purifi-audio-unveils-investigation-about-hysteresis-distortion
One of the interviews is at: https://audiophilestyle.com/ca/bits...eaders-qa-with-lars-risbo-bruno-putzeys-r815/ ...Also IIRC, the interview where they talked about Lars hearing it was a recorded audio interview. Seems to me there were maybe a total of three interviews that talked about the subject, but Lars hearing it was only in one interview.
Regarding discovery of the problem by human hearing, I was referring to the story Bruno and Lars told about finding a problem in their amplifier. Seems like they were talking about discovery of a problem in class D amplifiers, perhaps like Doug Self keeps describing new distortion sources in amplifiers. Maybe similar type of thing for Cherry. IIUC nobody is claiming discovery of a new physical phenomenon or anything like that.
EDIT: Another interview where it says: "Putzeys’ research of this phenomena was motivated by sporadic reports of a sort of 'granularity' in the sound reproduction with class D amplifiers."https://audioxpress.com/news/purifi-audio-unveils-investigation-about-hysteresis-distortion
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So absolutely no evidence of audibility, but a great way to differentiate a new product. And you hang on to this with terrier tenacity as if it's proof that you've been right on audibility of things all along...
Bill, IIRC I found the link to recorded interview before and you verified they said Lars heard it and told Bruno about it. Bruno also said a few customers reported it. Right now I can't find that interview, don't know if the website even exists anymore. However, IIRC there is post by me somewhere in the forum that gave the link to it.
EDIT: Post by billshurv: https://www.diyaudio.com/community/threads/ak4499eq-best-dac-ever.331363/post-6542086
Another: https://www.diyaudio.com/community/threads/ak4499eq-best-dac-ever.331363/post-6542108
EDIT: Post by billshurv: https://www.diyaudio.com/community/threads/ak4499eq-best-dac-ever.331363/post-6542086
Another: https://www.diyaudio.com/community/threads/ak4499eq-best-dac-ever.331363/post-6542108
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"Hysteresis happens in any coil that has a magnetic core." This appears to be saying "we should have known." I've heard the sound of a microphone transformer vs. without. Much more dramatically, I've heard a recording on a tape recorder made with a nonfunctioning bias oscillator. Ferromagnetic domains have hysteresis and change a varying current. As others posted, this was well known, but these designers, who are admittedly a lot smarter than me, didn't think an iron core inductor would affect a high end amp.
Lars, thanks for chiming in. Did I get the story wrong at all, as it was from memory of the interviews?
Also, as you probably know what people can or can't hear has been a controversial subject in forums for decades. Maybe research into 'Auditory Scene Analysis' will eventually shed more light. Any thoughts?
In this whole thread, there seems to be two points totally overlooked - the difference in rca level, and speaker cable, and length.
I can well believe that since the load impedance of interconnects is around 10k to 50k ohms, vegetable interconnects wouldn't sound much ( if any ) different to copper - as long as they don't form a battery, but speaker cables have much different resistive loads and power going through them, perhaps in this application the quality of the copper does matter, perhaps it doesn't. The best speaker cable test I've found was by sterophile magazine, they used big Tannoys and the results were thicker the cables are the better, considering Tannoy have a reputation of a high impedance, high efficiency and non reactive load, I can only imagine most speakers would benefit from REALLY thick cables, but then I only have just over 2 foot from amp terminals to speaker driver terminals, so do I need as good cables as someone with 25 foot lengths?
The same goes for capacitors, just because a difference might be audible in crossovers doesn't mean it will be audible in coupling capacitors and vice versa.
I can well believe that since the load impedance of interconnects is around 10k to 50k ohms, vegetable interconnects wouldn't sound much ( if any ) different to copper - as long as they don't form a battery, but speaker cables have much different resistive loads and power going through them, perhaps in this application the quality of the copper does matter, perhaps it doesn't. The best speaker cable test I've found was by sterophile magazine, they used big Tannoys and the results were thicker the cables are the better, considering Tannoy have a reputation of a high impedance, high efficiency and non reactive load, I can only imagine most speakers would benefit from REALLY thick cables, but then I only have just over 2 foot from amp terminals to speaker driver terminals, so do I need as good cables as someone with 25 foot lengths?
The same goes for capacitors, just because a difference might be audible in crossovers doesn't mean it will be audible in coupling capacitors and vice versa.
Mark, here are some newer write ups we did: https://purifi-audio.com/2020/04/28/dist/
and
https://purifi-audio.com/2021/10/14/some-speaker-problems-that-needed-solving/
Audibility: we do not have resources to conduct RCTs using panels etc. We suspect all kinds of distortion to be audible at some level and some conditions until proven otherwise. if we can lower distortion at a reasonable effort /cost we do it. We are not bothered if a panel of average listeners cant tell a difference. If just one person can repeatedly it’s interesting to investigate and pursue. We have done a project with an academic organisation. specialising in controlled listening tests where drivers with different levels of distortion were on trial. A a whole, the panel was not able to discriminate with statistical significance but our teams members could because we have build the experience to know what to listen for. I am sure the panel could be trained to tell as well. These tests are also hard to do since we do not have a zero distortion reference so it’s comparing distortion flavour A with flavour B