Mitch: To me, that is a very half-assed attempt at grounding a system. It is not only unsafe, it takes a lot of things for granted. Here are the reasons why i say what i do:
1) Using such an approach, all components are grounded through the chassis of the one chosen component. While one would think that this gets rid of the potential for a ground loop, all of the grounding taking place occurs via the negative conductors of the interconnects. Given the design of some interconnects, how much current do you think that they would pass before the circuit opened up? Once the circuit opened up in a safety situation, the only thing left to absorb the potential voltage & current would be you.
2) If the components are properly designed, the interconnects / RCA jacks are "floating" i.e. not physically connected to the chassis of the component. As such, you could ground the chassis of the preamp ( or any other device ) and still not have a real ground.
3) If the RCA jacks / interconnects aren't electrically tied to the chassis of a defective component, that component would still be "hot" due to the lack of connection to ground.
4) Due to the situation in #3, you could end up with some of the components grounded and some of them not. This now gives you a difference in ground potential, resulting in the potential for a higher noise floor and / or ground loop.
Your best bet is to run an external ground wire from the Hydra to the outlet. Since everything is plugged into the Hydra, you still end up with only one common path to ground and it is a true electrical ground, not that of a chassis which could be "floating". Just make sure that your AC grounding system is up to snuff. Sean
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1) Using such an approach, all components are grounded through the chassis of the one chosen component. While one would think that this gets rid of the potential for a ground loop, all of the grounding taking place occurs via the negative conductors of the interconnects. Given the design of some interconnects, how much current do you think that they would pass before the circuit opened up? Once the circuit opened up in a safety situation, the only thing left to absorb the potential voltage & current would be you.
2) If the components are properly designed, the interconnects / RCA jacks are "floating" i.e. not physically connected to the chassis of the component. As such, you could ground the chassis of the preamp ( or any other device ) and still not have a real ground.
3) If the RCA jacks / interconnects aren't electrically tied to the chassis of a defective component, that component would still be "hot" due to the lack of connection to ground.
4) Due to the situation in #3, you could end up with some of the components grounded and some of them not. This now gives you a difference in ground potential, resulting in the potential for a higher noise floor and / or ground loop.
Your best bet is to run an external ground wire from the Hydra to the outlet. Since everything is plugged into the Hydra, you still end up with only one common path to ground and it is a true electrical ground, not that of a chassis which could be "floating". Just make sure that your AC grounding system is up to snuff. Sean
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