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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => AC Power and Grounding => Topic started by: David Kulick on May 04, 2020, 10:47:11 am

Title: What to buy for the stage power?
Post by: David Kulick on May 04, 2020, 10:47:11 am
I've inherited the soundman position at our local 55+ community's theater, apparently because I'm the only one who read the manual for our Soundcraft GB4-32 board. I did help out the former soundman and learned a lot and basically I can handle the tribute bands that we tend to book.

I was reading an interview in the Sweetwater mailer and he casually mentioned the importance of line conditioners on the stage power, and I've always considered that the stage power outlets weren't the cleanest. I don't know what other things are on those circuits but I'm thinking maybe it would pay to put something between those old stage floor outlets and the various keyboards, amps, guitar boxes, etc.

I started looking through Amazon for electric line conditioner and don't know what would help, if any would. We don't need rack mounting (the rack has a conditioner) and that would likely create problems physically plugging things in so I'd stay away from rack mount stuff. So what do you recommend I do? We don't have much of a budget but most of the serious items are around $100 and I can do that for one or two.
Title: Re: What to buy for the stage power?
Post by: Kevin Graf on May 04, 2020, 11:34:37 am
In that 'power conditioner' is an undefined term.  It could mean almost any combination of the following.

a)  Noise filter - a low-pass EMI/RFI filter.
b)  Surge protector - although it's better to have surge protection at the home's service entrance.
c)  UPS - note that many UPS's are not really UPS's!
d)  Line voltage adjuster.
e)  Balanced power transformer.
f)  Isolated power transformer.
g) DC blockers.
h) Regenerators (PSAudio)
i)  Power Factor Correction
j)  I forget? But I think that there are more.

But in general, it's just a profit item for a vendor.
Title: Re: What to buy for the stage power?
Post by: David Kulick on May 04, 2020, 11:53:07 am
I've read reviews from audiophiles on some of these things and how much better the system sounded after using a particular item. I don't know, I have a decent surround sound system that does have a fancy UPS/Conditioner but it's to keep Florida storms from frying it. I don't know that it sounds better with or without. Mostly I listen to live (often bootleg) shows so I'm used to hums and less-than-pristine sound. I was once at a Zappa Halloween show at the old Felt Forum and had front row seats, right in front of the PA. My ears rang for three days. I'm lucky I can hear anything as I'm closing in on 70.

But there are times when something on the stage is humming we move it to another outlet or try a different cable. Something usually works. I do have one guy that plays fairly often and his box of guitar pedals always hums somewhat. I've just always wondered if something "cleaning" the power would help.

Title: Re: What to buy for the stage power?
Post by: Stephen Swaffer on May 04, 2020, 12:29:12 pm
Short answer-most of those hums are caused by things other than "noisy" power.

For lightning protection, I prefer a very low tech disconnect (switch) when not in use.
Title: Re: What to buy for the stage power?
Post by: Tim McCulloch on May 04, 2020, 12:32:44 pm
Hi David-

Power conditioning requires the previous application of power shampoo - lather, rinse, repeat.  ;D

Others here can speak more specifically but for the most part the PoCo is delivering "clean" juice to your building.  What happens on your side of the meter is another matter.

What is dirty power, anyway?  Without a definition how will you know if you're correcting a problem or applying a placebo? (Hint:  search for posts by Guy Holt here at PSW and follow the links in his posts).

Any building can have self-inflicted power problems, often created by volunteers or staff (or even licensed electricians trying to cut costs for the client).  Things that "work" by themselves become problems when there is a current path between them, read on:

In the altruistic sense it would be best to figure out *why* you have issues with stage power rather than apply more devices.  Chances are good that somewhere, in at least 1 circuit, you have a hot/neutral swap... and somewhere else you have a neutral/ground swap.  See the potential for a problem here?  If the circuits never meet (in a conductive sense), they will power a device and possibly without issue.  Things go to shit when those meet with a human in between.
Title: Re: What to buy for the stage power?
Post by: Brian Adams on May 04, 2020, 12:58:48 pm
In all my years and the hundreds if not thousands of stages I've been on, I've never seen a "power conditioner" for stage power. Sure, each rack usually has one in there (except amp racks), but it's more for power distribution than filtering of any kind. The power run to the backline (or most things) is never filtered, and I run plenty of "sensitive" equipment straight from the distro with nothing in between.

That said, Furman has some nice units that do some useful things, like not turning on power if the voltage is way out of range, or you have 2 hots, for example. Super nice features to have, and I recommend them, but I wouldn't buy them for the "filtering" they claim.

Don't trust reviews from audiophiles. Sure, having nice equipment can make a difference, but a $6,000 power cable isn't really any better than a $6 one. There'a A LOT of snake oil in that industry. So much so that it's hard to tell what (if anything) is real.

If you're not trying to correct any specific issues, buying "line conditioners" isn't where I'd recommend you spend your money. And if you are having issues, they probably aren't the right answer.
Title: Re: What to buy for the stage power?
Post by: David Kulick on May 04, 2020, 05:23:26 pm
That's why I ask these things here. I'll stick with regular cheap surge protector strips, thanks.
Title: Re: What to buy for the stage power?
Post by: Mike Caldwell on May 04, 2020, 07:51:58 pm
That's why I ask these things here. I'll stick with regular cheap surge protector strips, thanks.

A cheap power strip would be the last thing I would want to lay out on a stage for stage power if for nothing else you know the power switch on it will get bumped off at the wrong time.

For real stage power distribution here is where you want to look.
https://www.oawindsor.com/ (https://www.oawindsor.com/)

Title: Re: What to buy for the stage power?
Post by: Dave Garoutte on May 04, 2020, 11:13:04 pm
Go for the  squid  (https://www.cablestogo.com/product/29803/18in-16-awg-1-to-4-power-cord-splitter-1-nema-5-15p-to-4-nema-5-15r-taa-compliant) type power splitter.  More versatile, no off switch and plenty of room for wall warts
Title: Re: What to buy for the stage power?
Post by: Kevin Maxwell on May 05, 2020, 10:45:40 am
Learn how to test the power outlets. Get a cheap plugin tester to start and an NCVT. It wonít tell you everything but it will most of the time at least show you some faults. One of the first things you want to check is, are the outlets old and worn and barely able to keep hold a power cord plugged into it? Those will need to be replaced.

I would strongly recommend that you find a reputable electrician that has experience in entertainment wiring and first talk to them and tell them what you are trying to accomplish. Then have them come in and check all of the outlets that you will be using. Some might be miss wired and some might be old and worn and some might not have the wiring to it properly tightened. I have experienced all of those and more and the problems that come with that. That is why some of us always tie in and provide the power distribution ourselves and donít trust installed outlets.

Here are 2 links to a place that sells the devices that I would recommend you get to do some initial tests. I am not necessarily recommending this seller it is one of the first that popped up when I did a search.

Receptacle tester https://www.alliedelec.com/product/klein-tools/rt110/70811173/
And a NCVT (NON-CONTACT VOLTAGE TESTER) https://www.alliedelec.com/product/klein-tools/ncvt-2/70145306/
Title: Re: What to buy for the stage power?
Post by: Jeff Bankston on May 06, 2020, 05:15:52 am
If it aint broke dont mess with it. However it is a good idea to have a licensed electrician preferably and old guy with decades of experience to check receptacles, and all ground and neutral busses in panels. If theres a transformer have him check that the XO is wired correctly. I was sent to help a guy finish a warehouse job and the companies BEST electrician didnt ground the XO. I am a retired commercial electrician. 

Also that audiophile stuff is mostly crap. A friend worked at 3 different audiophile stores here in lost angeles in the late 80's and early 90's. The amps, preamps, speakers, turntable were awesome but the super dupper power cable, $50,000 speaker cables, $20,000 cord plug are all BS.
Title: Re: What to buy for the stage power?
Post by: Ike Zimbel on May 06, 2020, 09:29:00 am
But there are times when something on the stage is humming we move it to another outlet or try a different cable. Something usually works. I do have one guy that plays fairly often and his box of guitar pedals always hums somewhat. I've just always wondered if something "cleaning" the power would help.
One habit I got into a long time ago was to always look at the AC plugs on back line equipment. First, to check to see if the ground pin hand been broken off (bad!) and secondly to see if a replacement plug had been wired in. In the 2nd case, very, very often, the wiring was incorrect and needed to be re-done.
WRT your question about "cleaning" the power: If everything normally works and then the occasional set-up is noisy, the problem is with the set-up and not with your power.
Title: Re: What to buy for the stage power?
Post by: Mike Monte on May 10, 2020, 10:23:23 am
I've inherited the soundman position at our local 55+ community's theater, apparently because I'm the only one who read the manual for our Soundcraft GB4-32 board. I did help out the former soundman and learned a lot and basically I can handle the tribute bands that we tend to book.

I was reading an interview in the Sweetwater mailer and he casually mentioned the importance of line conditioners on the stage power, and I've always considered that the stage power outlets weren't the cleanest. I don't know what other things are on those circuits but I'm thinking maybe it would pay to put something between those old stage floor outlets and the various keyboards, amps, guitar boxes, etc.

I started looking through Amazon for electric line conditioner and don't know what would help, if any would. We don't need rack mounting (the rack has a conditioner) and that would likely create problems physically plugging things in so I'd stay away from rack mount stuff. So what do you recommend I do? We don't have much of a budget but most of the serious items are around $100 and I can do that for one or two.

First of all I am wary of most anything put out from a vendor: You definitely need "this".... (means watch-out to me)  Most of the time it's an "upsell"...just like going to a restaurant, ordering a meal and asking the waiter "Do you know what wine pairs well with this?" When asked, the waiter n-e-v-e-r recommends the house (least expensive) wine.....

Assuming that the room is not a 500 seater, IMO to be very accommodating the bands should get three dedicated 20 amp circuits; one for PA, one for stage power, and one for lights.  All outlets should be stage-side. 
Bands usually bring their own extensions, etc.
If you want to be really nice you could get two of these:
https://www.sweetwater.com/store/detail/PDX430--hosa-pdx-430-power-distribution-cord-30-feet?mrkgadid=3274464262&mrkgcl=28&mrkgen=gpla&mrkgbflag=0&mrkgcat=livesound&lighting=&acctid=21700000001645388&dskeywordid=92700046938738817&lid=92700046938738817&ds_s_kwgid=58700005283820807&ds_s_inventory_feed_id=97700000007215323&dsproductgroupid=411569127080&product_id=PDX430&prodctry=US&prodlang=en&channel=online&storeid=&device=c&network=g&matchtype=&locationid=9002142&creative=250341283160&targetid=pla-411569127080&campaignid=953755110&gclid=EAIaIQobChMI_rP0yrmp6QIVwZyzCh0aowwtEAQYAiABEgLv4vD_BwE&gclsrc=aw.ds
and run one across the front of the stage and one along the back wall of the stage.  This, however, will increase your liability as there will be more things to trip on....

Not knowing the room, the best investment (already mentioned) would be to hire a licensed electrician to verify that the power is on the up'n up.  This way you'll know what you have to work with on the get-go.

If you mention to the manager of the 55+ Community that you have some safety concerns about the stage/room power (voice your thoughts in an email to the manager) you can get every breaker/outlet labeled during the inspection and it may not even come out of your budget.

safety first.....