Max, you might have a reasonable approach. Diffmaker might work in this case. I might be able to set it up with my new PC and its high quality Sound Module, that I haven't even fired up, because I have no immediate use for it.
I have been waiting for a better instrument than my HP 3563, which is an SRS, than many of us have seen demonstrated at AES, but I might be able to do it with what I have. See how things get done? I'm just a tired old man, but I can be inspired too!
I have been waiting for a better instrument than my HP 3563, which is an SRS, than many of us have seen demonstrated at AES, but I might be able to do it with what I have. See how things get done? I'm just a tired old man, but I can be inspired too!
In order:
1. Me.
2. Null to the same level as a 30 m-ohm resistor, i.e., better than 120dBFS. I may have even posted the files at some point. I did send them to someone who was a "believer," and he publicly confirmed that they were indistinguishable.
3. Random noise in both cases, same as any loopback.
In every single measurement, the results were indistinguishable from a cheap resistor. It's easy to find lots of positive "reviews" of any placebo (not just in audio) that has a good story behind it.
Fraud or performance art, take your pick.
Not just according to jn. You left out all the other people (including the referees who rejected it from the same engineering journals that publish other papers of his that aren't obviously wrong) who found the major flaws.
Only usual power mains network distortion. Measured thru 1:2 voltage divider.
Attachments
Dither Ain't Dither....
'Signal' is never plain signal...it always signal PLUS noise PLUS distortions (plural) PLUS distorted signal PLUS distorted noise PLUS distorted distortions (plural)...and so on...IOW typically a sorry mess.
Changing the nature of the system noise will exponentially change the nature of the final audio resultant.
Dither is touted as a cure all, so how come differing dithering sounds so subjectively different ???...Hint, try mixdowns on Cool Edit for example using differing dithering...IME the resultants are profoundly subjectively different !.
Dan.
'Signal' is never plain signal...it always signal PLUS noise PLUS distortions (plural) PLUS distorted signal PLUS distorted noise PLUS distorted distortions (plural)...and so on...IOW typically a sorry mess.
Changing the nature of the system noise will exponentially change the nature of the final audio resultant.
Dither is touted as a cure all, so how come differing dithering sounds so subjectively different ???...Hint, try mixdowns on Cool Edit for example using differing dithering...IME the resultants are profoundly subjectively different !.
Dan.
Last edited:
Maybe they live in the nanotubes. Max, they go to great effort to emphasize the causally impossible separation of signal and noise after the fact. I've posted pictures of the horrible 1/f noise on a typical LP, lets see the removal of this with no effect on the low frequency musical content.
Last edited:
If you change the spectral distribution of a noise floor, it can certainly sound different. Nothing remarkable about that, this is why you have those options in sound editing.
Dither is not a "cure all," it is a cure for a particular disease- quantization. And indeed, even with different dither types, quantization distortion disappears.
That doesn't mean he's correct, it just means that he has difficulty admitting error. That seems to be common in fashion audio...
As I said, only a Maxwell demon can distinguish signal from noise. All non-intelligent things can do is filter or apply non-linearity, thus perhaps adding some modulation noise. Such signal distortion might sound better, but it is actually worse.Max Headroom said:
Dragging dither into this discussion just adds statistical smoke to the quantum smoke. Dither, when done properly, adds linearity to a quantised system at the expense of adding some noise too. Like all engineering, there is a balance to be struck.
The claim, as I understand it, is that the BQP removes noise (and intermodulation?) from the signal. To do that it would need to know which electron movements are part of the signal and which are part of the noise/IM etc. Only a demon can do that.
Picking The Difference...
In my experience to do these kind of 'Diffmaker' measurements a totally stable clock or preferably a master clock system is required.
Using typical PC or outboard USB 'soundcard', drift becomes a major problem when trying to compare immediately subsequent loop back recordings.
IME over a typical three minute song, about only 15 seconds or so can be sufficiently time aligned to derive a valid deep nulling and thereby pick out a valid differential that can then be amplified and analysed, either by ear or other methods.
Dan,
Thanks John, if I can inspire you I consider that as a sincere compliment....the reciprocal is already true.
In my experience to do these kind of 'Diffmaker' measurements a totally stable clock or preferably a master clock system is required.
Using typical PC or outboard USB 'soundcard', drift becomes a major problem when trying to compare immediately subsequent loop back recordings.
IME over a typical three minute song, about only 15 seconds or so can be sufficiently time aligned to derive a valid deep nulling and thereby pick out a valid differential that can then be amplified and analysed, either by ear or other methods.
Dan,
Last edited:
In other words, you're guessing. As opposed to actual measurement displays such as PMA's.
Yes. At the time, he had very little understanding of what it takes to measure low impedance circuits.
Not just according to jn. You left out all the other people (including the referees who rejected it from the same engineering journals that publish other papers of his that aren't obviously wrong) who found the major flaws.
And I at least was nice about it. Man, some of the other people who addressed the article really trashed Malcolm. I was quite taked aback by the level of animosity displayed by some.
You've taken half the fun out of it. I'm waiting for JC to explain it electrically without resorting to guessing games.
The clipped waveform is asymmetrical.
And, the 1.2 volt neutral drop was not explained. Either it's a 30 foot length of #14 at 15 amp draw, or it's asymmetrical coupling between hot/neutral, and ground. Or, it's the effects of another draw in the lab, which would put all data into question, as in, is it the device, or is it something external.
Shabby test methodology.
jn
Perhaps BQP just changes the nature (spectral distribution) of the base system noise, and thereby ends up changing the audio system final output resultant, perhaps profoundly because of successive stage behaviours....think IMD modulating IMD modulating IMD.....
If this is the case I would expect mid-fi systems to benefit rather more than hi-end blameless audio systems.
That is why i posed the question in a previous post....anybody here have experience of BQP on audio systems of differing performance levels ?.
Dan.
Last edited:
Come on John, are-you REALLY an electronic engineer ?
Or don't you like Champagne ?
Last edited:
Dither Bother...
In my understanding dithering 'randomises' quantisation errors, however the seed (noise shaping) is not random, therefore causing differing subjective resultants according to the 'randomness'.....IOW you don't get ought for nought !.
Panasonic MASH, Sony SBM etc etc all sound different....some ok, some drive me out of the room.....I expect this is the basis of preference of NOS output stages of some listeners.
Dan.
Uh huh ???...the distortion changes sure, but it don't disappear...THAT would be inciting so called Maxwell demons !.
In my understanding dithering 'randomises' quantisation errors, however the seed (noise shaping) is not random, therefore causing differing subjective resultants according to the 'randomness'.....IOW you don't get ought for nought !.
Panasonic MASH, Sony SBM etc etc all sound different....some ok, some drive me out of the room.....I expect this is the basis of preference of NOS output stages of some listeners.
Dan.
last part first...
If we assume a reasonably low IMD of say, .01% lets do the "IMD on IMD" calculations.
.01% is 1 part in 10,000. Or, 10e-4.
If we "believe" IMD has in itself, IMD...the next level would be 10e-8.
Kinda low numbers, no?
I'd be more inclined to believe that introduction of a lumped element in the powerfeed system could lessen the dI/dt of the supply bridge diodes as they switch from high impedance to low, and low to high. A lumped inductance can indeed alter the spectra of the conduction switching.
What does Jack call the little wiggly thing in the waveform, Intermodulation? Intermodulation of what? Line, line harmonics, or music?
jn
Last edited:
- Status
- Not open for further replies.