You know, there have been pages and pages about this cap distortion bull **** and DA stuff and no clarity on the issue has emerged.
So fcuk it - I'm just going to go for direct coupling and be done with it.
As for RIAA - do it in DSP or move over to CD ( that'll be high res downloads for you Richard!)
Down with caps! Period!
So fcuk it - I'm just going to go for direct coupling and be done with it.
As for RIAA - do it in DSP or move over to CD ( that'll be high res downloads for you Richard!)
Down with caps! Period!
But they make very effective tone controls....and what would the tube world do without them ?.
Dan.
Is the discussion now veering from alleged DA nonlinearity (of which there appears to be no evidence, but some anecdotes) to general dielectric nonlinearity (which has been well known and studied for decades)?
Still trying to understand the meaning of all the previous controversy about DA ;-)
Some people having a different definition of DAs in their subconscious ? I mean, some took the poor linear model to define the physical phenomena and want an other acronym for what is not modeled that we are seeing in the measurements?
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Yes.
Hot babes to the rescue!
An externally hosted image should be here but it was not working when we last tested it.
se
A remarkable claim was made that DA is the cause of nonlinearity. When evidence was sought (and that took a lot of pressing), it was not forthcoming. So... draw your own conclusion.
Richard made comment of 'silence between notes' with low DA caps.
Can particular cap dielectrics a exhibit a Barkhausen effect like noise ?.
Dan.
Can particular cap dielectrics a exhibit a Barkhausen effect like noise ?.
Dan.
For a small diversion Digital Cables and Noise | AudioStream a quite remarkable example of getting not only the wrong end of the stick, but completely the wrong stick!
Just a note on measuring distortion. Today the method of choice is a DSP based system that uses FFT. This allows fairly precise identification of the level of the fundamentals and each harmonic.
The prior generation of test equipment used a notch filter to tune out the fundamental. The Noise and Distortion was just often read on a meter. Now to get a % reading the fundamental was adjusted to a reference level before the notch filter. Now what is interesting is that even with linear distortion that reduced the fundamental the harmonics would read higher!
So when reading older papers the method of measurement comes into play.
The prior generation of test equipment used a notch filter to tune out the fundamental. The Noise and Distortion was just often read on a meter. Now to get a % reading the fundamental was adjusted to a reference level before the notch filter. Now what is interesting is that even with linear distortion that reduced the fundamental the harmonics would read higher!
So when reading older papers the method of measurement comes into play.
An externally hosted image should be here but it was not working when we last tested it.
Where did you get that picture of my wife ???
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Let me try again.
DA is modeled with multiple Rs and Cs and that model cannot lead to or explain nonlinearity.
But we don't know whether this model is all there is to DA, do we? It explains charge/recover cycles, but that's all it does because that's all we ask of it (the model).
We seem to agree that nonlinearity is impacted by DC bias on a cap. We know that DA, in a situation of changing DC bias, impacts the value of DC bias with time. So it appears that there might be a basis for a causal link between DA and nonlinearity. Bateman found 'a' link but we don't know it is causal.
Where in this reasoning did I go wrong?
Jan
DA is modeled with multiple Rs and Cs and that model cannot lead to or explain nonlinearity.
But we don't know whether this model is all there is to DA, do we? It explains charge/recover cycles, but that's all it does because that's all we ask of it (the model).
We seem to agree that nonlinearity is impacted by DC bias on a cap. We know that DA, in a situation of changing DC bias, impacts the value of DC bias with time. So it appears that there might be a basis for a causal link between DA and nonlinearity. Bateman found 'a' link but we don't know it is causal.
Where in this reasoning did I go wrong?
Jan
No references anywhere on that. In fact no mechanism I can think of for that oft repeated "silence between notes" too close to memory and echos for me frankly. You see how this DA thing got carried away.
It's a standard term. You can read the definition in just about any electronics text. For measurement methods, refer to MIL- C 19778.
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