Funniest snake oil theories

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#8,902
marce said:
Eh, I think you may have read it wrong could you try and find the relevant passage,....
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So what about an asynchronous USB interface, isn’t it supposed to completely isolate the DAC from everything? Let’s look in detail at each part of the system and see what affects it.

Let’s start with the local oscillator, the “clock”. It turns out that almost all ultra low jitter oscillators are quite sensitive to ground plane and power supply noise. As the noise increases the jitter increases, and the spectrum of that extra jitter is directly related to the spectrum of the noise. This phenomenon is well known by many digital designers, so many will use decent low noise regulators with the clocks, but many don’t bother with that step, guaranteeing that the low jitter spec of the oscillator is going to be drastically compromised. Not only do you have to deal with the self generated noise of the regulator, but also its ability to block noise coming in on its input supply. Most regulators are very poor at this for high frequencies. This means that noise generated by the other logic elements on the board is going to sail right on through the regulators used in many DACs, causing jitter in the clock whose spectrum is highly correlated to what the rest of the board is doing. It IS possible to do a good job of providing low noise clean power to the clock, but it’s not easy and the designer really has to work at it.

And we still haven’t even talked about the ground plane! The noise on the ground plane is just as important to the jitter of the clock, but it doesn’t have a regulator, it just is what it is. If the clock is going to do what it is supposed to do, the ground plane it is connected to HAS to somehow be isolated from the noise generated by other parts of the circuit. I’ll go into this in detail later on.

So right at the beginning the clock itself is susceptible to influences outside itself in almost all implementations.

Read more at Q&A with John Swenson. Part 2: Are Bits Just Bits? | AudioStream
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This is all just Digital 101.
It's all a compromise between fast data signal rise times causing power/ground disturbances, and slow rise times causing data slice threshold uncertainties.
Fully agreed EMC techniques of controlled power/ground current loops and power decoupling is the first part of the solution.

Perhaps much of this becomes moot with DAC chips claiming high clock jitter immunity.
The question is, how good is this immunity, and what are the audible effects of clock jitter spectrum that that is present...ie is the system clock jitter transformed to a different jitter spectrum that is in fact subjectively worse ?.

Jocko has/had much to say about jitter spectrum down to ULF being critically important subjectively.

Dan.
 
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#8,903
More audio tweak tripe....
Something most of us worry about when listening to music is distortion and signal loss degrading our beloved music. Since the audio signal is magnetic in nature, it can be controlled and preserved through the use of magnetic conduction.

Magnetic conduction is a new patented form of conduction, implementing specially arranged magnetic fields to concentrate the signal within the conductor. The electrons of the audio signal have a quantum spin which gives them their "magnetic moment" or charge. It's this charge which allows the electrons to react with magnetic fields. So if we use a magnetic conductor instead of a regular conductor, we can guide the electrons (the audio signal) through the conductor in a very precise way to reduce distortion and signal loss.

Imagine this electron stream is an audio signal. In a regular conductor, the signal would be hazy and sparse, resulting in distortion and signal loss. In a magnetic conductor however, its magnetic fields attract the electrons into the center of the conductor, preventing escaping electrons and preserving signal integrity.
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I don't recall any such tweak product being panned quite so badly.
There were pluses. Dynamic peaks were peakier: In the portions where the ensemble's two pianists were both playing rather loudly, my system seemed marginally louder than it did without the Adapters. But removing them also removed from the sound a film of murk whose presence I had not at first detected. Without the HFC products, the violins again stood proud of the other instruments, and the oboe line became more audible and intelligible.

With the Adapters, the pace was laggy and lackluster, and the reverb-drenched spoken intro sounded desultory and, again, tired; with the Adapters removed, this broadly paced tune was rhythmically more on track, and more purposeful: Les Thompson's mandolin accents on the downbeats now seemed to push the band in a straight rather than a straggly line.

Read more at Listening #159 | Stereophile.com
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Dan.
 
#8,904
Max Headroom said:
This is all just Digital 101.
It's all a compromise between fast data signal rise times causing power/ground disturbances, and slow rise times causing data slice threshold uncertainties.
Fully agreed EMC techniques of controlled power/ground current loops and power decoupling is the first part of the solution.

Perhaps much of this becomes moot with DAC chips claiming high clock jitter immunity.
The question is, how good is this immunity, and what are the audible effects of clock jitter spectrum that that is present...ie is the system clock jitter transformed to a different jitter spectrum that is in fact subjectively worse ?.

Jocko has/had much to say about jitter spectrum down to ULF being critically important subjectively.

Dan.
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I had read that but my brain tend to freeze reading a lot of this stuff, reading on autopilot, but as you stated it is digital design 101.... sounds good if you don't understand digital as one commentator put "After reading all of this it makes one wonder how digital works at all"...
 
#8,906
A standard marketing ploy is to describe some feature of your product as though it is unique to your product, when in reality all competent/legal products of that type must necessarily have that feature. Everything which is said is true, yet deeply misleading to Joe Public. If you are really lucky some ignorant 'technical' journalist will magnify the effect of your words.
 
#8,908
DF96 said:
A standard marketing ploy is to describe some feature of your product as though it is unique to your product, when in reality all competent/legal products of that type must necessarily have that feature. Everything which is said is true, yet deeply misleading to Joe Public. If you are really lucky some ignorant 'technical' journalist will magnify the effect of your words.
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#8,913
Another example of what a total **** that guy is and half his surrounding minions, this measurement thing is also starting to grate, without measurement's you wont get anywhere.... I am trying to avoid Audiophilic ranting's as they make me iller than I already am and tend to mess up my Karma... Its never ending rants against engineering practices including measurements and this belief that audio designers should be like luthiers tuning the sound of their designs to their sound.....
 
#8,917
billshurv said:
I despair. I few weeks ago he 'cleansed' the comments sections so his acolytes could post their support of his views without fear of common sense entering the discussion.

But why he chose to pick on SL is beyond me. He is (IMO) one of the good guys.
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Got a link please.... or do you mean he did to others what he did to me, ban me for not towing his line... these are the people at the back of the queue when freedom needs to be defended, at the front of the queue complaining about abuses of freedom, yet given chance and power they become the most vile despots literature (or more correctly Internet ramblings) allows them to be.
 
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