Simplest Linear PSU?

@itsjustme 

On the topic of SMPS (switched mode power supplies) the problem is noise.  Noise CAN be controlled, but it is difficult. 

Thank you - the first intelligent post on this thread.

That is the issue - linear power supplies vs switched mode power supplies.

The early switched mode power supplies were awful, spewing out rf and noise both into the circuitry and back into the mains. New generation switched mode power supplies are much better now, but personally I still prefer a linear power supply - ease of repair and if properly designed more headroom.

there are no serious audio-grade SMD components,

Hilarious  

"audiophile" with size, shape, lovely colour, gold plated leads, pc triple c copper leads, aged, brewed - I have a bunch of audiophile components in the spares bin that were easily outperformed by "non audiophile" components.

SMD can offer huge advantages in short signal paths, more controlled rf floating around, less leakage, more accurate solder joints ( by the way solder joints - no 2 are the same, even the shape of the solder joint can induce distortion )

But @lewm is correct here - most audiophiles have no idea and make assessments based on labels on components and audiophile jewellery. A bit of machined aluminium inside the case sends most audiophiles into raptures - completely unaware of the dodgy solder joints. 

I recall asking my tech about a stereophile class phono stage all the rage - he said "the case looks nice, but I lost count of the dodgy solder joints".