Tell me how circuit A can be better than circuit B.
The current drawn by each stage create voltages between stages. Signal reference has to go through these small resistances and colect these voltages. With hierarchical ground these voltages are minimized by creating a very short and direct path for signal. It's been long known as "signal follows ground".
I believe you mean the reservoir capacitors currents? Where do they go? Read Kirchoff. They don't need a ground for closing the loop.
What mistake?
Profound misunderstanding. DC (as well as AC) has no home. Current exists in a loop. In taht respect, all points of teh loop are of equal importance. Calling one ground, or reference, or whatever, is a useful convention for circuit analysis.
Hierarchical ground, of course.
Doesn't make sense to me. Because of resistances introduced by wiring, and circulating currents, nothing is a "zero point". It's an abstraction, but when dealing with noise you can't rely on t, you have to consider all parasitics.
That's why chassis should never be used as an "audio ground". And for teh same reason, a dedicated ground should not make loops.
Correct. Same for many guitar amps, because guitar players have always been used to hum and buzz. The balance between the bonus of extra volume and the nusance of noise is still positive.
I don't need to research it. As I explained in another post, I used it to carry an unbalanced signal with an impedance of 200 ohms across several kilometers of cable.
Of course, currents should be separated as much as possible.
There's no doubt DC heaters are the best choice for low noise. It depends on the expected level of noise performance.
However I've seen poor implementations of DC heaters where incorrect filtering resulted in increased buzz compared to AC heaters. 50/60 cycles doesn't coupled too well capacitively, but their harmonics do.
As I said, I've had very good results with star grounding in audio amplifiers, all analogue, no digital signals.
Perhaps my explanation isn't clear.
It comes down to this for me. Treat the unbalanced input ground as the quietest ground point in the circuit. By referencing my HV regulators to that ground the dc from the regulator is as quiet as the input, assuming the regulators work. Mine do.
The star point is connected to the PS via a fat trace for lo z return.
Each successive stage (2 more, a gain then a follower) has their signal ground attached to the star which keeps the amplified signal referenced to signal ground. Returned dc from the stage may go back to the PS ground or the star ground depending on the current.
The output stage, power supply and it's filter bank of my hybrid amp 200 wpc mosfet amp live on a separate board, thus charging and output ground return currents never see the star point. There is a connection between the output stage ground, with no charging currents, and the star ground.
There is little to no signal at the output ground terminal referenced to the input ground. The point being there is no modulation of DC return paths with AC signal current.
The safety AC line ground is isolated by a 10k resistor in parallel with 2 6 amp diodes in parallel in opposite directions which bleeds off tiny ac leakage currents under .6 volts. If there should be a short to the chassis the diodes will conduct and blow the fuse or trip a house breaker. So the chassis is at signal ground and will connect with earth ground in case of a fault. Meanwhile there is 10K isolation between signal/chassis ground and AC line ground reducing or eliminating ground loops.
The overarching theme is to be conscious of the nature and magnitude of the ground currents and where you want them to go and how that will affect circuit performance.
Critique all you want. Stand up on a soap box ll you want. Doesn't bother me.
