one of the earliest examples that just fired up some electricity
in my stagnant brain cells..

aparently Billy Fury needed a good slap bass sound
to make his 1st LP sound more like authentic yank rockabilly..
but couldn't find any credible sounding brit session players..

so they recorded the parts played on electric bass
and mixed in the sound of another player slapping the muted strings
on a stand up acoustic bass in time with the electric.

..and that would have been about half a century before
'convincing' bass sample Vsti instruments
became easily and cheaply available..