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What I am talking about is leaving out the death cap, which is totally supefluous and more hassle if you actually have a 3-wire AC mains setup, (the 3rd-wire being the ground or earth wire). The cap is there to provide signal coupling between earth and chassis ground. You want the chassis to be referenced to earth ground and not to float in order to shield stray RF. This coupling is achieved not by hard wiring, but via a .02-.05uF/400-600V capacitor.
Once upon a time in the old days of nonpolarized 2 conductor plugs, there was a 50% chance that a particular AC leg would be the one which was grounded. Hence the selector switch provided in some amps (that you can see in some old fender schemes) would connect one or the other leg to the chassis-coupling cap. If this cap becomes electrically leaky, you have a 50% chance that the chassis will be energized (@ 120VAC in the states, or 240VAC here in little old NZ, which, believe me, you don't want going thru' your body). Thats why you can get shocked when you touch chassis on some old equipment. Old caps can become leaky or can short in time and then pass high voltage current to the chassis.
With a 3 wire plug, you now have a real connection from chassis to ground via the earth wire. No way to mix it up, unless the venue's service is miswired. Thus, there's no reason to keep the old grounding ("death") cap.
What Enzo is saying is that the plethora of rules (or conventions?) that seem to apply in the US (probably for good reason) mean that you keep the earth wire separately bolted to the chassis (which come to think of it might lower the chances of it becoming inadvertently disconnected if you were altering the grounding inside the amp).
As Enzo is one of the most experienced magicians on this forum, you probably should heed his advice. Whereas I am not too humble to admit that I am just a passionate hobbyist, who has made some stupid mistakes, and doesn't want other people to make the same mistakes. ;-)
Once upon a time in the old days of nonpolarized 2 conductor plugs, there was a 50% chance that a particular AC leg would be the one which was grounded. Hence the selector switch provided in some amps (that you can see in some old fender schemes) would connect one or the other leg to the chassis-coupling cap. If this cap becomes electrically leaky, you have a 50% chance that the chassis will be energized (@ 120VAC in the states, or 240VAC here in little old NZ, which, believe me, you don't want going thru' your body). Thats why you can get shocked when you touch chassis on some old equipment. Old caps can become leaky or can short in time and then pass high voltage current to the chassis.
With a 3 wire plug, you now have a real connection from chassis to ground via the earth wire. No way to mix it up, unless the venue's service is miswired. Thus, there's no reason to keep the old grounding ("death") cap.
What Enzo is saying is that the plethora of rules (or conventions?) that seem to apply in the US (probably for good reason) mean that you keep the earth wire separately bolted to the chassis (which come to think of it might lower the chances of it becoming inadvertently disconnected if you were altering the grounding inside the amp).
As Enzo is one of the most experienced magicians on this forum, you probably should heed his advice. Whereas I am not too humble to admit that I am just a passionate hobbyist, who has made some stupid mistakes, and doesn't want other people to make the same mistakes. ;-)
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