Metal foil resistors often have current noise specifications, metal film typically do not. Why?
Depends on the resistor. E.g. the ones I use specify current noise.
https://www.vishay.com/docs/28713/melfprof.pdf
Yes of course since current noise is frequency dependent, thermal noise is not. That is all explained in the paper I linked to above. But if you read the LIGO graphs you should notice that e.g. in Susumu RG even the low frequency current noise is almost at thermal noise. And low frequency in this case is below 10Hz. Are you saying that the missing detail is below 10Hz?
What I said at the time what the effect was plainly audible, and to multiple people. It was not subtle. In some cases I provided more details about exactly what was different sounds. For some resistors the bass frequencies were far more affected than higher frequencies, which I stated at the time.
BTW, metal foil resistors have already been tried by Andrea, I found out a day or so ago. So, we'll see if they have an effect on this dac too. If they do, then maybe Acko can send the metal foil dac to Nautibouy and others to compare with a stock Marcel dac. We'll see.
BTW, metal foil resistors have already been tried by Andrea, I found out a day or so ago. So, we'll see if they have an effect on this dac too. If they do, then maybe Acko can send the metal foil dac to Nautibouy and others to compare with a stock Marcel dac. We'll see.
Yes, MELF resistors work very well for audio.
Here again is the link to the LIGO resistor noise paper:
https://dcc.ligo.org/public/0002/T0900200/001/current_noise.pdf
Here again is the link to the LIGO resistor noise paper:
https://dcc.ligo.org/public/0002/T0900200/001/current_noise.pdf
As AB testing was not possible all your resistor listening test results are just anecdotes regardless of the number of people involved.
Anecdotal evidence is still a type of evidence.
"In science, definitions of anecdotal evidence include: "casual observations or indications rather than rigorous or scientific analysis" "information passed along by word-of-mouth but not documented scientifically" "evidence that comes from an individual experience."
https://en.wikipedia.org/wiki/Anecdotal_evidence#:~:text=In science, definitions of anecdotal,comes from an individual experience.
For one example of anecdotal evidence:
The soliton phenomenon was first described in 1834 by John Scott Russell (1808–1882) who observed a solitary wave in the Union Canal in Scotland:
I was observing the motion of a boat which was rapidly drawn along a narrow channel by a pair of horses, when the boat suddenly stopped – not so the mass of water in the channel which it had put in motion; it accumulated round the prow of the vessel in a state of violent agitation, then suddenly leaving it behind, rolled forward with great velocity, assuming the form of a large solitary elevation, a rounded, smooth and well-defined heap of water, which continued its course along the channel apparently without change of form or diminution of speed. I followed it on horseback, and overtook it still rolling on at a rate of some eight or nine miles an hour, preserving its original figure some thirty feet long and a foot to a foot and a half in height. Its height gradually diminished, and after a chase of one or two miles I lost it in the windings of the channel. Such, in the month of August 1834, was my first chance interview with that singular and beautiful phenomenon which I have called the Wave of Translation.[3]
"In science, definitions of anecdotal evidence include: "casual observations or indications rather than rigorous or scientific analysis" "information passed along by word-of-mouth but not documented scientifically" "evidence that comes from an individual experience."
https://en.wikipedia.org/wiki/Anecdotal_evidence#:~:text=In science, definitions of anecdotal,comes from an individual experience.
For one example of anecdotal evidence:
The soliton phenomenon was first described in 1834 by John Scott Russell (1808–1882) who observed a solitary wave in the Union Canal in Scotland:
I was observing the motion of a boat which was rapidly drawn along a narrow channel by a pair of horses, when the boat suddenly stopped – not so the mass of water in the channel which it had put in motion; it accumulated round the prow of the vessel in a state of violent agitation, then suddenly leaving it behind, rolled forward with great velocity, assuming the form of a large solitary elevation, a rounded, smooth and well-defined heap of water, which continued its course along the channel apparently without change of form or diminution of speed. I followed it on horseback, and overtook it still rolling on at a rate of some eight or nine miles an hour, preserving its original figure some thirty feet long and a foot to a foot and a half in height. Its height gradually diminished, and after a chase of one or two miles I lost it in the windings of the channel. Such, in the month of August 1834, was my first chance interview with that singular and beautiful phenomenon which I have called the Wave of Translation.[3]
Is the hypothesis now that low level musical details somehow end up in phase in the non-inverted and inverted data streams and then cancel when the DAC signals are subtracted?
To an extent, yes. Not entirely of course. However, its typically enough so the ear/brain cannot deconstruct the pressure waves impinging on the ear drums as representing as much credible musical detail. With differential summing, low level musical details start to deconstruct as low level blurring of the sound. Why? To know that we would need to know how the brain does its trick of deconstructing a single pressure wave into a full symphony orchestra. Since we don't know exactly how that works at this point in time, we can only take note of the observed resulting sound that people report hearing.
hmm.. there is an original musical signal. positive branch is a copy (with gain) of it. Negative branch is an inverted copy of it. If there are places where these two are instead in phase.. then it's not low level part of the original, but is distortion, noise, whatever..
Maybe there is something going on somewhere but then explain it better, please.
Maybe there is something going on somewhere but then explain it better, please.
The body resonance of a violin does not sound like noise. Nor do the evolving vibrational modes of a drum head as the volume level decays. Either the information is there or its not. Noise is no substitute for a deterministic signal.
EDIT: However, I would agree that for systems that sound muddy, that adding some HD can give a perception of false clarity. That happens on poor systems, not good ones.
EDIT: However, I would agree that for systems that sound muddy, that adding some HD can give a perception of false clarity. That happens on poor systems, not good ones.
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but body resonance etc is entirely part of the original signal, and the inverted copy of it.. I see no way for it to become common mode noise or distortion.. - which instead will be removed..?
So why does it become a deviation precisely 'in phase' with each other? what mechanism..🤔
(note 'precisely' - if not that, than it's not removed..)
So why does it become a deviation precisely 'in phase' with each other? what mechanism..🤔
(note 'precisely' - if not that, than it's not removed..)
https://www.diyaudio.com/community/threads/return-to-zero-shift-register-firdac.379406/post-7441211
Then read (although the last paragraph was an add-on, not really part of the response to Marcel's question):
https://www.diyaudio.com/community/threads/return-to-zero-shift-register-firdac.379406/post-7441377
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Altough we can’t explain everything, what could be a sensible explanation that SE has something that differential hasn’t unless something is messed up in the process of getting the differential signals.
If so, the two differential branches would have a different sound.
Would be interesting to compare and hasn’t been tried so far to my knowledge,
Hans
If so, the two differential branches would have a different sound.
Would be interesting to compare and hasn’t been tried so far to my knowledge,
Hans
hm.. in the first quote you talk about the 'error terms' - that is not the original music material..
If you would have mentioned instead Bill Waslo and Diffmaker.. and the inner plays and difficulties with temporary phase shifts which should be compensated for.. then that would make me srart to think..
If you would have mentioned instead Bill Waslo and Diffmaker.. and the inner plays and difficulties with temporary phase shifts which should be compensated for.. then that would make me srart to think..
If you mean what I think you mean, the one of the differential-summed branches is inverted. That would already make it sound different on my system. It would need to be inverted again to remove that difference.