evaluating SMPS for audio

[buschfsu]

i have a scope (old crt) and am wondering if its possible to evaluate wal warts (smps) or bricks to select for audio applications like running opamp based phono preamps etc. so far im thinking measure the dc coming out and zoom in but that doesn't seem like it would tell me everything about how 'clean' the dc waveform is . any help is appreciated.

yes i know how to make a linear psu with a torroidal and a few caps/transistors but i have so many of these smps things. meanwell seems to be a decent brand and i have some medical grade supplies so very curious.

jb

 

[shabtek]

noise can vary with load
ac and hf are probably where all the action is

 

[k brown]

Maybe a crude, non-tech way to evaluate is to conduct listening tests comparing different SMPSs with clean battery power. Whichever sounds most like the battery is likely the cleanest supply.

 

[shabtek]

in another smps thread someone recommended cap coupling the ac component of the power supply into a mic pre to get a better look at the noise