- a 500Hz external filter is a good choice
Did you see the harmonic contents of the current pulses ?
To what frequency does that extend ?
I have more measurements, different currents, none really go any higher than 500Hz.
Why not filter AC from 500Hz ? The filter can be simple (40dB/decade) yet have good suppression up to about 10kHz where most transformers stop working properly.
- shape of the AC current waveform is relevant in this context
You are the professor in this field. What would happen if you were to filter at 100Hz ? Why doesn't anyone filter AC at just above 60Hz ?
Would there be enough power transfer into the smoothing caps ?
If one were to filter at 1kHz or 10kHz or 100kHz would that help with recharging the power caps?
Why would the current shape be not relevant when it is the current that charges the reservoir caps ?
- if rectifiers need any filtering or not (you flip flop on the topic)
Did I mention they did or did not ? Did I go into details about snubbering ? Did I address regulators (of different sorts ?)
This is about the mains side not what happens after the rectifier.
- anything EMC related that you just brought up
EMC is a wide subject. The discussed filter (that's what were taliking about) adresses various aspects of EMC of which only a small portion of differential mode is discussed which is not as important/impactful as common mode issues.
But if you read the thread and my and other comments you would have known this.
I think you know what you are doing.
The more you learn the more you realize you know next to nothing.
However, your statements are at times vague, at times not on point what matters, and at times not particularly useful.
And yours are ?
Just say what _matters_ according to you for a power supply in audio and what (if anything) an AC filter can bring to the table.
This is NOT a thread about power supplies this is a review of a mains power supply filter that has some of its aspects measured (not by me).
When you have comments about the review then post them.