Covid keeps me from traveling so have a lot more time and what better to do but go back to old hobbies 🙂
So I've got some old amp boards (destroying a few but I had many) LC Audio millenium and now building a dual differential or bridged balanced singled ended dual mono 2x300w amp using 2 Hypex SMPS 400A100 PS and other potentially interesting stuff which I will get to later if it works out.
I've placed the two amp boards inverted to each other which when looking at it makes it very convenient to place additional filter caps directly on the +- rails between the boards not involving ground.
The Hypex PS keeps the rails in check relative to ground meaning they wont wander and am I correct that adding caps for additional filtering between the rails (and not to ground) is all that I need to potentially improve power supply noise rejection?
I am a bit new to bridged amps and a pure balanced signal path and having had some serious ground OCD in the past I sort of struggle with the idea of not getting ground involved hence the ask for confirmation?
So I've got some old amp boards (destroying a few but I had many) LC Audio millenium and now building a dual differential or bridged balanced singled ended dual mono 2x300w amp using 2 Hypex SMPS 400A100 PS and other potentially interesting stuff which I will get to later if it works out.
I've placed the two amp boards inverted to each other which when looking at it makes it very convenient to place additional filter caps directly on the +- rails between the boards not involving ground.
The Hypex PS keeps the rails in check relative to ground meaning they wont wander and am I correct that adding caps for additional filtering between the rails (and not to ground) is all that I need to potentially improve power supply noise rejection?
I am a bit new to bridged amps and a pure balanced signal path and having had some serious ground OCD in the past I sort of struggle with the idea of not getting ground involved hence the ask for confirmation?
Between the rails close at the amplifier should be good for high frequencies.
Just look at an op amp, no ground (common) is necessary in concept. The potentials at the
various circuit nodes are all relative. Draw the circuit out with batteries for the supplies,
floating in space unconnected. It's isolated from the rest of the universe.
There is no absolute potential there, just one circuit node compared to another. Any of
the nodes can be the reference common point for the other nodes, even the output node.
When that circuit is connected to another circuit that does have a defined potential, it is then
that the nodes all take on potentials relative to that.
Just look at an op amp, no ground (common) is necessary in concept. The potentials at the
various circuit nodes are all relative. Draw the circuit out with batteries for the supplies,
floating in space unconnected. It's isolated from the rest of the universe.
There is no absolute potential there, just one circuit node compared to another. Any of
the nodes can be the reference common point for the other nodes, even the output node.
When that circuit is connected to another circuit that does have a defined potential, it is then
that the nodes all take on potentials relative to that.
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Actually, could I decouple earth from the smps somewhat in adding say a 2 ohm resistor?
If I understand correctly all the power goes through the rails in a setup like this.
If I understand correctly all the power goes through the rails in a setup like this.