The DSP correction possible with Meridian speakers can compensate to some extent for small shortcomings in drive units but these must be chosen to be of good performance and "fit for purpose" by the Meridian engineers. We know they do not just use any old rubbish.

As for making your own...

I use ATC active analogue monitors and, when I went to their factory, there were machines changing the cross-section of the copper wires from circular to a flatter shape to make the voice coils more space and thermally efficient. This must be the ultimate in "make it in house".

Malcolm