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Yes

4 (23.5%)

No

6 (35.3%)

Doesn't Matter

4 (23.5%)

Wire Nuts Are Evil

3 (17.6%)

Total Members Voted: 17

[Tommy Peel]

.....Amtrak is still around?!?

<back off track>
Yeah... I get stopped by one in one of the towns I drive through on the way to/from work occasionally. The train station is right by one of the main roads through town.

Of course being a local I know the way around it. 
</back off track>
<back on track>

[Steve M Smith]

When did railway (or railroad) stations become train stations?


Steve.

[Frank DeWitt]

Should I make this a new topic and write a short essay on it? That could be useful, I think....

Good question,  Can it be short?  To stand alone it should also include what a ground isn't  (hot all hum comes from ground loops.
so lets see

1 Hum is bad but is it a ground loop?
       Other common causes.
       How to tell.
2.  OK  Ground loop where?  How to tell
     The right way to break it and keep audio
           Balanced with phantom
           Balanced w/o phantom
                 mic level or line
                        install the fix at what end?
3  How not to fix it?

Perhaps some more on the other causes of hum and there fix
Do include your clamp on amp probe use.  I have never seen anyone else use it or talk about it.

Or just write a book and get rich?  Probably not.

[Stephen Swaffer]

we can only install what the customer wants or what the blueprints specify. you must understand WE the electricians HAVE TO follow the plans..... if i install ig recepts when a customer didnt ask for them i would have to pay the extra and that aint gonna happen. what needs to be done is the code changed for places that have sound systems.

By definition the NEC is concerned with fire and personel safety-proper functioning is not really their concern-and I would argue it should not be.  What SHOULD happen is that the people making the plans should be professional and competent enough to draw up plans that take into account the intended use of the facility and spec proper wiring.  I just did a remodel that spec'd isolated ground receptacles in 2 locations for IT equipment.  (Finding MC/BX cable with 2 ground wires is a pain-at least in Iowa-fortunately my inspector allowed me to remark a wire as the iso ground.) There is nothing preventing their being specified for audio or other technical uses.

Code was never intended to be "best practices"-but rather a minimum, hopefully safe install.

[Tommy Peel]

When did railway (or railroad) stations become train stations?


Steve.

I don't know... Maybe it's a Texas thing. That's what I've always heard them called.

Sent from my Moto X (XT1053) using Tapatalk

[Mark Cadwallader]

When did railway (or railroad) stations become train stations?


Steve.

Shortly after "automobiles" were referred to as "cars."  Don't let me get started on motorcycles being called "bikes"....

Mike, a sticky article on hum and ground loops would be great. Mark C.

[Mike Sokol]

Good question,  Can it be short?  To stand alone it should also include what a ground isn't  (hot all hum comes from ground loops.
so lets see

1 Hum is bad but is it a ground loop?
       Other common causes.
       How to tell.
2.  OK  Ground loop where?  How to tell
     The right way to break it and keep audio
           Balanced with phantom
           Balanced w/o phantom
                 mic level or line
                        install the fix at what end?
3  How not to fix it?

Perhaps some more on the other causes of hum and there fix
Do include your clamp on amp probe use.  I have never seen anyone else use it or talk about it.

Or just write a book and get rich?  Probably not.

Actually, my next book is going to be "No-Shock-Zone for Sound Systems" or something like that. I'm writing it over the winter and should release it next spring. One full chapter is dedicated to identifying and solving ground loop hums in sound systems.

While my editor says I can't write my own name in less than 250 words (he's probably correct) I can probably boil this procedure down to a simple bullet-point list of how to test for ground loop currents with possible solutions in order of preference and price. That would make for a good chapter close, especially if it could fit on a pocket card.

If I do come up with a bullet-point test list for ground loop hum, then you guys will need to test it and give me feedback on the procedure. Does that sound like a fair deal? 

[Frank DeWitt]

.
If I do come up with a bullet-point test list for ground loop hum, then you guys will need to test it and give me feedback on the procedure. Does that sound like a fair deal? 

I would like to be in that loop.  Please keep us current on it.

[Jeff Bankston]

When did railway (or railroad) stations become train stations?


Steve.

Dont know. Got to do with where choo choo go. Mongo only pawn in game of life.

[Jeff Bankston]

When a building or club design is in the works the electrical architect designs the circuts for the code lighting and power requirements. Its up to the business owner to know that they need to specify seperate panel(s) for sound system use only. There would be a panel for general receptical/lighting use and panel(s) that only power sound system recpticals. The sound system panel(s) can power multiple I.G. receptiacls on the same circut , deticated circut I.G. recepticals , and the seperate circut I.G. receptical. The panel(s) can be powered from an isolation transformer and would have its own grounding wire to the cold water pipe , etc. BUT this has to be part of the design. I wired a few nightclubs and the club owners didnt know anyting about electrical. They are businessmen not electricians. There is the cost factor and extra panel(s) and transformers and I.G. recepticals can easliy add a 5 gigit cost factor that the owner(s) might not want to spend to get better sound. We played in clubs that had awful house pa systems and when i said they otta get a better sounding pa the response was > the people come and drink and are probably to drunk to know or even care. It all comes down to money. If th customers complain about the sound the club owner(s) might do something about it. All they seen to care about is if its loud enough.

btw I have about 80 HO locomotives. no amtrak

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