i know this is a old post, but i had to resond to the old crap thing lol, well its quite the opposite, old caps and diodes were bomb proof if they were made in the UK and USA, british standards have always been of higher rating when compared to CE mark, cheap imports go way back and quality control was sketchy from the import countries, and they were used in well known brands over here, so things did start going south quickly once the imports increased. As for rectifiers, heat dissipation is the reason for multiple diodes, too condensed the harder it is to control thermal runaway, tolerance in diodes is pretty close regardless, manufacture of the doped region is very accurate and consistent in silicon diodes, the issue is always cooling and constant flash voltage/current, modern machines fail much more than older types, they're build is inferior by far, caps are pure junk these days and tolerances are a joke in most well known brands too, one last mention in diodes, if you use lower current rated caps, expect fail rate to go up, any transients will wipe one or more very quickly, so double up on protection for surge and spikes
