Low Cost AC Regenerator

This is not a regenerator. It is a voltage regulator. Now whether it creates quality power is up to the design of the components but that isn’t it’s primary function. It is designed to handle transients and protect a wide variety of equipment. I won’t say that it is impossible that this makes good power to run an audio system but I would say it is unlikely.

A regenerator made with audio is mind is your best bet.

Jerry

I just connected an imported lowish cost step down conditioning transformer that takes my 240V (nominal, sometimes higher) supply and outputs to 230V and to 220V outputs.

This followed two boxes needing repair, supposedly due to overvoltge. I would otherwise have stayed with a 'normal' power conditioner. My components have 220 on the back of some, 230 on the others. 

It's sounding good so far, but it's  barely had time to warm up yet.

It would surprise me very much if any component is manufactured that is damaged by 240 V.  240V is standard here in the US (along with 120V).  My voltages runs as high as 124V/248V and nobody complains of damaged equipment.

Here in the US we used to call outlet power "110 V" and saw some components marked 115V.  I think these numbers were conservative, more like a minimum voltage, since many items are more likely to be damaged by undervoltage. 

So does your transformer sound good?  An oversized transformer can be a good thing to power an amp from.  So it may not be a waste of money (as it seem syou suspect).

Jerry