How do you know the digital engine is simply acting like a simple low order non-linearity? If not no conclusions can be made about the audibility of x THD under all circumstances.
I believe that you are in good faith here but any real speakers are already orders of magnitude over these numbers and if it is simply an addition of like distortion hearing the difference is truly an extraordinary claim.
Yes, if it were. But, apparently its not. Certainly doesn't sound like it is, perceptually speaking.
Lots of work to do to make a very strong case out of one isolated experiment.
One may recall that it took Martin Seligman 20-years of published research to overturn Skinner's Behaviorism. I don't have the time or the interest to do whatever it takes to overturn certain audio design engineer beliefs. Respectful disagreement is fine for now.
It must be different IMD then. Probably is, if one did spectral analysis vs amplitude vs frequency.
Perhaps we can change that.
Unless of course you really want to discuss Bybees and Goop.
I thought it was Chomsky that bet his career on taking on Skinner. BTW many years ago my wife and I went to an open house (the for sale kind) at Skinner's house.
At this juncture the more interesting question would be how we could measure what is going on. And once we have a could are we able to make it happen?
Seligman experimentally showed that 'learned helplessness' couldn't be properly accounted for by Behaviorism. His contemporaries kept insisting it could be fully explained by Behaviorism. Seligman eventually won the argument, but it took a lot of published experiments to rule out every claimed behavioral explanation.
Chomsky and Skinner disagreed about the extent to which language is innate or learned. Their disagreement was perhaps more famous because it largely took the form of spirited debate, rather than a series of dry scientific publications.
It was only later, coming out of the end of behaviorism, that psychology became much more of an overall experimental science, rather than fundamentally theoretical.
For practical purposes, behavioral approaches are sometimes still applied, although they tend to be much more effective with animals other than humans.
Chomsky and Skinner disagreed about the extent to which language is innate or learned. Their disagreement was perhaps more famous because it largely took the form of spirited debate, rather than a series of dry scientific publications.
It was only later, coming out of the end of behaviorism, that psychology became much more of an overall experimental science, rather than fundamentally theoretical.
For practical purposes, behavioral approaches are sometimes still applied, although they tend to be much more effective with animals other than humans.
Nelson Pass built a circuit with a low order 2nd's transfer function. I don't recall anyone seeing an effect at levels anywhere near -120dB (in fact the circuit is not capable of going that low).
I would start with actually measuring the output of the DAC vs. register settings, not exactly rocket science.
There is only one name for IMD, but like CP (cow pictures) the details are not all the same.
Right now I am working on other things. As I said, my primary interest in the time I have available is not to change the thinking certain audio design engineers. Maybe someone else would like to do it. If so, I would be happy to help out as I can. I do have software code that could be used to make the adjustments.
What I can say for now is that small adjustments of the registers show FFT results consistent with changing only one harmonic component at a time.
Fine you believe your peeking ears, but I actually think this is worthy of testing further. If you are able to supply the board you did the tests on and code to test with I'm willing to help pony up some beer tokens for someone to try and measure it.
The exact dac I used is too large to ship. I could provide a dac board with the same dac chip, a USB board to feed it I2S, and an Arduino with code to program it. The experimenter would need to provide +-15v, +5v, power supplies, and would probably need to fashion a 3-opamp output stage for which a schematic could be provided. I do have a reasonably low distortion discrete output stage I could send, but don't know if its distortion can go as low as a good OPA1612 output stage (I would suspect not). If someone were serious about doing it, it would probably take me a few days to collect everything together and draw up an interconnection diagram.
EDIT: Alternatively, I could order an Iancanada output stage board and then send it combined with a different dac board. Distortion should be low enough and it should simpler to work with than the other option described above.
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If you agree to expand on these details, then I would agree to expand on the Dead Milkmen CP.
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