Simplest Linear PSU?

Acopian -- industrial strength, quiet, not audiophile-priced.

Don’t be too critical of SMD. For semiconductor devices, the exact same dies are available in old fashioned THT and SMD. Difference: packaging. Packaging may affect heat rating, but for power applications you will find the devices are THT. In many cases newer devices with better performance are ONLY available in SMD.

Look more deeply.

As noted, if you understand the stuff, build your own. I do and they outperform pretty much anything you can afford to buy.

I'll also take issue with "simplest" implying that simpler is better. The best are not that simple. Mine are not that simple.  I use combinations of active and passive noise elimination.  Simpler would be nisier.

I really like sola Linear PS which can be had on ebay for a song for things like NUC PS. For more critical stuff, Sparkos Labs have the best dead silent mostly assembled boards for DIY. Peace

I just bought a Teddy Pardo LPS for my Node N130. It was a simple install and it sounds great!

+ for Pardo….i run a bevy of them including 24/7/365 servers…for years…zero issues