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[George Friedman-Jimenez]

Tom, are the ground prongs of the 3 prong socket connected to the chassis grounds of power strips? I thought they were connected to each other and to the third prong of the plug, but not necessarily to the chassis ground that would contact the rack rails.

Cliff, it is interesting that you have never had ground loop problems in a live setting. I would have thought there would be even more electrical noise in live environments than in a home studio where I at least have several separate dedicated circuits.

[TJ (Tom) Cornish]

Tom, are the ground prongs of the 3 prong socket connected to the chassis grounds of power strips? I thought they were connected to each other and to the third prong of the plug, but not necessarily to the chassis ground that would contact the rack rails.

Yes - metal enclosures are grounded to the earth ground in most cases. 

[Clint Miller]

Cliff, it is interesting that you have never had ground loop problems in a live setting. I would have thought there would be even more electrical noise in live environments than in a home studio where I at least have several separate dedicated circuits.

No... The only noise I encounter now is caused by single coil pickups and neon signs.  there is a bar called Cliffside in Akron that an old cooler on the other side of the stage wall causes a crazy amount of noise in any distorted guitar sound.  I can't find any way to defeat that!  I put the bass player there last time and as soon as he hit his fuzz pedal, the noise went crazy!

[George Friedman-Jimenez]

So if multiple rackmounted 15A power strips are all tied to a common ground by the rack rails, there should be no need for a distro at all, as long as no single audio component draws over 15A. Assuming we can find separate 15A circuits in the venue (which we would need to find anyway with a distro), we can just plug each power strip into a different circuit and not worry about ground loops through the building wiring. Is that correct?

[Charlie Zureki]

So if multiple rackmounted 15A power strips are all tied to a common ground by the rack rails, there should be no need for a distro at all, as long as no single audio component draws over 15A. Assuming we can find separate 15A circuits in the venue (which we would need to find anyway with a distro), we can just plug each power strip into a different circuit and not worry about ground loops through the building wiring. Is that correct?

  Hello,

   Not necessarily.  These ground-loop hums are fickle.  You should not have a ground-loop hum if  both grounds are at the same voltage potential, but, you may need some very accurate measuring gear to measure/verify any potential difference.

   Hammer

   

[TJ (Tom) Cornish]

So if multiple rackmounted 15A power strips are all tied to a common ground by the rack rails, there should be no need for a distro at all, as long as no single audio component draws over 15A.

Yes - this is exactly the point.  You don't really have a "distro", you have consolidated grounds on all the independent 120v circuits you are using.

[George Friedman-Jimenez]

The problem with it is, as many have correctly pointed out, the there is danger having an open neutral that would become "live", or "hot".

Is this a potential risk in a venue with unknown wiring issues, when using multiple separate circuits with grounds all connected? Or does physically connecting the grounds prevent this problem?

[Ivan Beaver]

Is this a potential risk in a venue with unknown wiring issues, when using multiple separate circuits with grounds all connected? Or does physically connecting the grounds prevent this problem?

That really depends on the rest of your system-the gear in it-how the wiring/grounding scheme (on the signal side of things) is handled.

If you have gear with a pin 1 problem or are running unbalanced lines etc, you can have all sorts of hum buzz problems.

Saftey will not usually be a problem (assuming all the grounds go back to central point).

Of course if you have gear with pin 1 problems and other signal grounding issues, then having a "proper" distro/grounding system is not going to fix those.

As a general rule, the electrical ground should be used as a saftey and not relyed on for "noise control".

[Bob Leonard]

Could one of the moderators put this thread out of it's misery please.

[Spenser Hamilton]

Could one of the moderators put this thread out of it's misery please.

I agree with Bob, this thread has taken a few steps past ridiculous.

I can easily run a 3-way rig, 2 monitor mixes, backline power and 8 led cans off of a 15A circuit. It covers 150-250 people no sweat and I can't remember ever blowing a breaker. Why people need to be playing "electrician" for these little club shows is beyond me.

[ProSoundWeb Community]