SMPS's are excelent products for cleaning up your mains supply.

[Music or sound]

I have mentioned in another thread that I do have a lot of SMPS's in and around my audio system.  The Devialet's themselves, Mutec MC3+USB, the SOtM kit, lots of AV kit, computer and so on.  Not good I am sure.

One thing I am thinking of doing is to sell the sPS-500 power supply that came with my SOtM bundle and buy two Paul Hynes SR4 LPSU's.  So losing one SMPS and replacing with two LPSU's.  From a conventional audiophile perspective, this should be the way to go.

The above has got me thinking though, the sPS-500 is actually designed to clean up mains noise.  To quote from SOtM:

The sPS-500 is an audio power supply designed specifically for high performance audio. It is built to eliminate noise generated by powered devices as well as to simply remove noise coming from an AC power source.

Using SOtM’s unique technologies for noise cancellation and sound enhancement, and high quality audio components that are already proven in sound quality, you will hear superior sound improvement with the well-designed sPS-500.

So maybe if I resign myself to the fact that I will always have some SMPS's around (AV kit etc.), having a SMPS like the sPS-500 powering the kit nearest to my Devialet might actually be the optimum solution.  Not conventional thinking, but it might be true?  A pair of Paul Hynes SR4's certainly has more "audiophile credibility" than the sPS-500, would it really be better?

I think SMPS are noisier than LPS if not implemented well but a good designed SMPS can be less noisy than LPS with big transformers. I got some Meanwell SMPS for some of my LED lighting and they have much lower impact on my music than the transformer they replaced. That said I have plugged all my computers, phone chargers etc. (bad SMPS) in a power purifier which resulted in better sound than plugging my stereo equipment in it.

SMPS have higher frequency noise which can be more effectively filtered. LPS have often large toroid transformers which are not necessarily the best option but because there were originally expensive (much less now) items from military purposes they are considered often the best choice. R or C core transformers have better DC filtering but they are rarely used