I think it’s time to file this stuff and listen to the music or we will be sliding into the pit of digital inaccuracy again. :eek::D
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And under the Nyquist /Shannon sampling theorem there is nothing super sacred about 44.1khz at all, rather the theorem holds true for use of much higher sampling to be used ,representing twice the upper most audio frequency to be moved upward, and I would suggest twice from its present limiting figure. https://earthworksaudio.com/wp-conte...yond-20kHz.pdf
The benefits would be less severe brick wall filtering between 20khz and 22.05, and catering to our ability to perceive frequencies higher than 20 khz. The CD standard has had a number of developments to lengthen available space. https://en.wikipedia.org/wiki/Rainbow_Books that may enable the same 79 mins but with extended frequency.
Going back to where this thread commenced the discussion quoted but not necessarily agreed to, was on a downward spiral path to reduce audio frequency to be lower than 20 khz, as I recall 15 khz being suggested. The opposite namely a doubling of upper frequency being what is actually needed by audiophiles using digital replay. The Denon 103 cartridge as example of earlier/ present technology having frequency response of 20 hz to 45 Khz
Here is a great example of just that Marco,
Dc Direct current, despite being hundreds of years since its discovery has received very little research , here is the Wikipedia article about DC https://en.wikipedia.org/wiki/Direct_current
"A direct current circuit is an electrical circuit that consists of any combination of constant voltage sources, constant current sources, and resistors. In this case, the circuit voltages and currents are independent of time. A particular circuit voltage or current does not depend on the past value of any circuit voltage or current. This implies that the system of equations that represent a DC circuit do not involve integrals or derivatives with respect to time."
but then contradicting this is
"If a capacitor or inductor is added to a DC circuit, the resulting circuit is not, strictly speaking, a DC circuit. However, most such circuits have a DC solution. This solution gives the circuit voltages and currents when the circuit is in DC steady state. Such a circuit is represented by a system of differential equations. The solution to these equations usually contain a time varying or transient part as well as constant or steady state part. It is this steady state part that is the DC solution. There are some circuits that do not have a DC solution. Two simple examples are a constant current source connected to a capacitor and a constant voltage source connected to an inductor. "
We can see the discussion of DC involved with differential equations usually collapses as a pure mathematics exercise https://www.youtube.com/watch?v=CRLXDnViSyI
but is then awkwardly limited in how it relates back to the actual application in a DC circuit, rather it gets caught up in itself - happy that it has solved the mathematics
Moreover what tends to happen is the former limiting explanation "A particular circuit voltage or current does not depend on the past value of any circuit voltage or current" takes precedence. , so really exciting applications involving DC ( like I do ) get totally ignored, and commented on as being impossible. We see the conventional explanation of DC above containing explanation "the circuit voltages and currents are independent of time" An example contrary to this being the thyristor used in a DC circuit where the end of the circuit instructs the beginning, or where a gate or base of a semiconductor placed at the end of a circuit instructs the beginning of a circuit to commence.
which is then unexplained or contrary to conventional thinking. But the annoying thing is that there are devices readily available that solve a lot of problems in electronics - that is when and if they are applied. Hence the study of DC needs expanding, to place time as a real factor in DC circuits.
Thanks for that, Chris. Most of it goes over my head, but I understand the basis of where you're coming from. Certainly, I've always admired how you're able to think outside the box and apply some lateral thinking to the subject of electronics:)
Marco.
This article gives a pretty clear explanation: https://people.xiph.org/~xiphmont/demo/neil-young.html