Oh great. Now I need one of those cameras
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More fascinating than David Letterman dropping watermelons off a rooftop. 
This was good
Somebody has released new music on an Edison Cylinder! Techmoan explains
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Here’s Veritasium’s clarification of his “The Big Misconception About Electricity” video about energy not flowing in wires, it’s very good:
How Electricity Actually Works - YouTube
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So how do you at PS Audio think of circuit design?
Skip to 21:20 and see the comments by Rick Hartley, circuit board designer, then watch the vid.
Given my little brain, it appears to me that if you don’t consider the fields, you may be compromising sound quality. No?
Any PS Audio engineer want to weigh in? Ted?
Peace
Bruce in Philly
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I just finished watching How Electricity Actually Works. It made much more sense this time over his initial video. And Rick Hartley’s comment about circuit board design was an eye-opening WOW moment for me.
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Me thinks…just my .0002 that Paul and PSA Team already knew
this stuff…
Best wishes
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It’s especially important with 100MHz to GHz ranges in your design.
Roughly the field shape for DC signals is that everywhere is the same. For GHz signals the return current will flow very closely following a trace. Differential pairs are your friend. If you instead have a single trace on the surface, the return current will use whatever path is around it. If you have a ground plane that’s solid under the trace everything is fine. If you have interruptions in your return current path (say a trace across the ground plane) then things go awry quickly. You can help by using caps of the right size to help the return signal “hop” over any discontinuities that are necessary for other reasons.
But for audio frequencies the field shape is much more like DC. It’s quite wide and often can be assumed to be as big as the whole board. In the MHz and 10’s of MHz range I think of the return path as a rhombus with two opposite corners at the source and destination of a trace and the other two corners in the middle. The higher the frequency the narrower the middle. In general, I use differential traces at much lower frequencies that most designers and I keep any non-control signals (e.g. clocks, data from the digital inputs, etc.) that aren’t differential separated by ground on all sides (the layer above, the layer below as well as the traces on either side.)
We also need to pay attention to things like the skin effect to make sure the trace can carry the current necessary at its operating frequencies.
Besides good CAD tools that can do field analysis of your boards, there are some simpler “calculators” that are very useful. E.g.
Saturn PCB Toolkit - Saturn PCB Design | Saturn PCB Design
[Edit: I guess you could say that I intuitively see the fields all of the time that I’m working on boards. I could never get away with that lack of precision if I were doing RF boards, etc.]
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But why then are such techniques such as star grounding popular? Everything just flows down to the same place eh?
Peace
Bruce in Philly
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Field solvers can help to understand anything, but they are slow and cumbersome. Learning shortcuts can save a lot of time figuring things out, as long as you remember when those short cuts are valid.
Most audio grounding problems are relatively low frequency so simply assuming current follows wires is fine. Star grounding cuts out current loops (or at least minimizes the current in the loops which include your interconnects, etc.) That is good.
Things like RF interference are a little more complicated and you have to do a little more work to understand them and treat them.
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This also ties in nicely with those who “fear” the use of PC boards for audio circuits and prefer point-to-point wiring. A properly designed PC board is a much better controlled set of transmission lines than any direct hand wired circuit. Key words are “properly designed PC board”.
#21 far left gate, 81-1 
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That was an amazing run. It seemed like the seas parted for him all they way except for the last bit and then he just wanted it more than the rest of them. Great stuff!
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It’s really amazing the diverse content on YouTube. When the war started, the algorithm pushed this to my list. I’ve been following it ever since. This is supposedly one of two super yachts owned by Putin. The dimensions of it are staggering. The yearly maintenance alone is a minimum of 3 million dollars. That doesn’t cover charter costs which include food, crew, fueling and berthing costs.
I saw where there was another big yacht captured (for lack of a better term) and the estimated cost was $1billion.
The World’s Biggest Wave Explained:
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