You are here

Well, yeah, again, electric shocks from mics !!

For performing musicians and engineers: stagecraft, engineering and gear.

Re: Well, yeah, again, electric shocks from mics !!

Postby funky54 » Tue Sep 03, 2019 3:28 pm

I didn’t read 11 pages. This thread is a little over my head.

For 30 years I have done a few things to protect myself.

First, I have two really good power conditioners with surge. One for PA and One for my guitar amps.

Second, I try to plug PA, guitar amps into the same circuit if at all possible

Third, I never plug lighting in on the same circuit with anything else band related (and in truth I’m about to go all LED anyway)

Last, this one may seem like voodoo... I have a bag full of large “O” shaped strong magnets that open in the center. Each and every cable near the user end is wrapped 3-4 times through the magnets and then are sealed wrapped in twine.

Now make fun if you like, but I’ve set up my 6600 watt PA, Wet Dry Wet guitar rig in every Victorian Home converted to biker bar, tavern, bar, wedding, school gym, County Fair, State Fair imaginable, and have never experienced ground loops or a shock through a mic.
funky54
Poster
Posts: 32
Joined: Mon Sep 02, 2019 3:57 am

Re: Well, yeah, again, electric shocks from mics !!

Postby Hugh Robjohns » Tue Sep 03, 2019 4:48 pm

funky54 wrote:....and have never experienced ground loops or a shock through a mic.

It's nothing at all to do with your weird magnet voodoo* ;) or even your (pointless) power conditioners... and everything to do with having properly maintained and grounded equipment, with balanced connections and all plugged into the same mains outlet...

H

* It might be worth reading up on the very well understood physics of static wires carrying alternating currents wrapped around magnets (Flemings left hand rule), and also the effect of coiling wires carrying alternating currents around metal cores (inductance).
User avatar
Hugh Robjohns
Moderator
Posts: 24818
Joined: Fri Jul 25, 2003 12:00 am
Location: Worcestershire, UK
Technical Editor, Sound On Sound

Re: Well, yeah, again, electric shocks from mics !!

Postby ef37a » Tue Sep 03, 2019 7:15 pm

Hugh Robjohns wrote:
funky54 wrote:....and have never experienced ground loops or a shock through a mic.

It's nothing at all to do with your weird magnet voodoo* ;) or even your (pointless) power conditioners... and everything to do with having properly maintained and grounded equipment, with balanced connections and all plugged into the same mains outlet...

H

+ 1 and FFS get an RCD! Preferably one that is hard wired into the main supply cable so you cannot forget it.

Dave.
ef37a
Jedi Poster
Posts: 10724
Joined: Mon May 29, 2006 12:00 am
Location: northampton uk

Re: Well, yeah, again, electric shocks from mics !!

Postby cyrano.mac » Thu Sep 05, 2019 5:10 pm

I've lost a dear friend to this kind of foolery, so I learned the hard way...

If you're in doubt about anything mains related, don't play. That's my rule.

A good solution is to buy an isolation transformer. If your amp is connected through it, you still might get shocked, but at least you won't die from it. Unless you're foolish enough to put one hand on one side of the transformer and the other on the other end.

You'd still have to hope the rest of the setup is ok, but seeing that tube guitar amps are the worst offenders, it's a big advantage.

Our entire live setups are connected through big isolation transformers. These were installed for safety, but also solved a problem of magnetic interference. There's a 750 KVA - 500V transformer across the street, feeding the trams. It was there already before our old building was constructed, so not much reason to complain. It resulted in a hum in some equipment. Nobody could solve it, until the decision was made to invest in isolation transformers everywhere. The hum was only a problem in one place and there it depended on equipment used. It could be horrible and it could be hardly noticeable.

The main argument was safety, but it also solved the other problem. Everybody's real happy now.

And since it's legal in the UK to "steal ground", it's even more important than elsewhere.
cyrano.mac
Regular
Posts: 75
Joined: Sun Jun 02, 2019 5:00 pm

Re: Well, yeah, again, electric shocks from mics !!

Postby funky54 » Sat Sep 07, 2019 4:55 am

Hugh Robjohns wrote:
funky54 wrote:....and have never experienced ground loops or a shock through a mic.

It's nothing at all to do with your weird magnet voodoo* ;) or even your (pointless) power conditioners... and everything to do with having properly maintained and grounded equipment, with balanced connections and all plugged into the same mains outlet...

H

* It might be worth reading up on the very well understood physics of static wires carrying alternating currents wrapped around magnets (Flemings left hand rule), and also the effect of coiling wires carrying alternating currents around metal cores (inductance).

Gotta ask, why do you feel power conditioners are pointless? They do a great job at removing hum and static sounds. Not to mention smooth voltage. Mine might even serve as the very transformers your talking about. They also have indicator lights to let you know if your grounded, out of phase, hot neutral wire, and a few other responses that I can’t remember.
funky54
Poster
Posts: 32
Joined: Mon Sep 02, 2019 3:57 am

Re: Well, yeah, again, electric shocks from mics !!

Postby Hugh Robjohns » Sat Sep 07, 2019 11:35 am

funky54 wrote:Gotta ask, why do you feel power conditioners are pointless?

To be fair, there are power conditioners... and power conditioners... and there are mains supplies and mains supplies! I'm not sure where you are based, but we are blessed in the UK to have well engineered mains supplies which are generally pretty clean and stable. I know that's not the case for all parts of the world...

Most power conditioners -- the lower cost ones (although none are cheap!) -- don't do very much at all, and probably actually make the problem worse rather than better because they raise the impedance of the mains power source as a whole. And the filtering they apply is typically only a duplication of what is built into any decent equipment anyway. I tried a very expensive power conditioner on my main hi-fi system a few years back, and even the sales rep had to agree it made the system sound worse, rather than better! :lol:

To really 'condition' the mains properly is complicated and expensive, and although there are some units that do a genuinely good job, they're not what most people purchase!

They do a great job at removing hum and static sounds.

A power conditioner can't remove hum... That comes down to the ground wiring and avoiding any magnetic coupling...

A power conditioner can sometimes help reduce HF noise if you have a particularly dirty incoming mains supply, but the power supplies inside the individual equipment should do that too. And if the incoming mains is badly contaminated it might be better to have a word with the supply company to get that sorted out at source (such as by switching your building to a different phase)!

Not to mention smooth voltage.

If you mean regulate the mains voltage, yes, some can -- those with auto-transformers, for example. However, modern equipment with SMPS supplies can cope with a very wide range of incoming mains voltage anyway, and even legacy equipment with linear power supplies are pretty tolerant of the typical voltage variations of normal mains supplies.

They also have indicator lights to let you know if your grounded, out of phase, hot neutral wire, and a few other responses that I can’t remember.

Sure... added value... but if you're worried about the mains supply suddenly becoming L-N reversed you can buy a plug-in mains tester for very few sheckles. :-D

So really, all these apparent benefits are generally unnecessary, redundant or just frippery, with a side order of potentially making the power supply worse, rather than better.

I've tested a fair few mains conditioners in the studio over the years, and I can't say I've ever noticed any real repeatable benefits, not even from the really expensive ones. I don't need a display to tell me the mains voltage, or lights to confirm the socket is wired up correctly. The rack lighting can be useful, but much cheaper rack lights are available. And the surge-protection, while theoretically useful, is rarely effective in my experience -- at least, not more than once! :-)

In all honesty, I've never had a mains-supply related problem in the studio -- no static clicks, no hums, no problems with varying mains voltage, no damaging surges... -- and that's just because the studio gear is wired up sensibly, the equipment is well-designed, and the incoming mains supply is pretty reliable.

Okay, so occasionally we get the odd blackout when a tree gets blown into the overhead mains cables coming into the village... but a typical mains conditioner couldn't solve that problem anyway, and for situations where supply continuity is essential I use an on-line UPS which basically regenerates its own clean sine-wave mains power from a constantly-charging battery.

Sorry if my views clash with your own... but that's my take on it. Years back I followed the dogma and used power-conditioners, but the more I understood about them the more I realised how pointless most really were, and I've not used them here for over 20 years with no negative aspects at all.

H
User avatar
Hugh Robjohns
Moderator
Posts: 24818
Joined: Fri Jul 25, 2003 12:00 am
Location: Worcestershire, UK
Technical Editor, Sound On Sound

Re: Well, yeah, again, electric shocks from mics !!

Postby ef37a » Sat Sep 07, 2019 11:36 am

Can I guess Funky 54 that you are not in UK?

Most of us here get a very "civilized" mains power feed. Most folks are served through a buried, armoured cable from a BIG mother substation transformer (like the size of a small house!) This means virually nothing is induced RF wise into the mains feed. The ground is all that armour in the soil so very good indeed.

Voltage stability* is generally good, so good in fact that I doubt many people bother to monitor it? Because of the massive sub traffs the source impedance is very low (compared to a Pole Pig I would guess?) and so loads going on and off have little effect.

Our 13A fused plugs and the fact that they are now almost univerally factory moulded means reversed live and neutral does not happen. In any case an expensive "conditioner" is not needed to tell us that! £20ish buys you an excellent Martindale mains socket tester and you can take it to gigs.

Ad hoc isolation transformers and balanced mains carry serious third party safety risks but others here will have professional knowledge of this.

Waaaay back in the day we had a lot bother with the introduction of transistor audio products. Fridges were a constant pain but the filters I made did a FAR better job of stopping the crack when connected in the mains supply TO THE FRIDGE than in the mains to the audio devices.

*In any case, I have long been of the optinion that good quality mains powered kit should be designed to cope with a fair degree of dirt on the supply and surely everything has on board regulators where it matters these days?

You beat me to most of it Hugh! Just like to add? Heaven knows how good our electrical supply would be had it not been nationalized and put on a "war footing"? Whatever the colour of your politics, some things I think are just too important to be left "to the market". We did however recently have a million or so people disconnected, I was one of them for about an hour. AFAIK that was just two(!) power stations going off line and not in the midst of a very cold winter. I hope that is not an indication of future trends?

Dave.
ef37a
Jedi Poster
Posts: 10724
Joined: Mon May 29, 2006 12:00 am
Location: northampton uk

Re: Well, yeah, again, electric shocks from mics !!

Postby funky54 » Sat Sep 07, 2019 12:51 pm

I have two of these. One is branded Tripp-Light and the other says Eaton, but I’m pretty sure it’s the same OEM. They were originally for very very large commercial copiers.

Maintains usable 120V nominal output to sensitive electronics during severe brownouts and overvoltages. Prevents surges and spikes from damaging circuitry. Filters out potentially disruptive line noise.
Ideal for computers, routers, modems and home theater components
Corrects under- and overvoltages in 89V–147V range
Protects against spikes with 1440 joules of surge suppression
Monitors power status with front-panel diagnostic LEDs
Features 6 NEMA 5-15R rear outlets
2-year limited warranty
$25,000 Ultimate Lifetime Insurance


Where I have noticed them really making a difference is in very old homes built in the late 1800’s early 1900’s some having two conductor cloth rapped wiring. (Where I grew up there was an entire district of bars taverns, restaurants all from converted Victorian homes) I also have noticed it cleaning up the sound at some outdoor events where the power was sketchy and from lots of extension chords, big old schools. There is a very old firehouse that has become a venue for weddings that most devices make buzz and hum sounds until I plug these in. Quiets everything.

Last I know in one venue prior to my acquiring these we blew fuses all the time and had to try and use bare minimum gear, once I started using these we stopped blowing fuses.
funky54
Poster
Posts: 32
Joined: Mon Sep 02, 2019 3:57 am

Re: Well, yeah, again, electric shocks from mics !!

Postby Hugh Robjohns » Sat Sep 07, 2019 1:30 pm

ef37a wrote:I hope that is not an indication of future trends?

I very much fear that it is Dave.

I happen to know that there has recently been a lot of work done by various organisations and essential businesses at the behest of the Government to plan for potential power outages of up to 5 days! Yes, 5 days!!! Needless to say, none currently can cope with anything like that duration...

I'm talking here of hospitals, broadcasters and the transmitter sites, supermarkets, fuel stations, water and sewage treatment facilities, gas pumping stations, and so on and so forth... Most of these facilities have back-up generators already, but few have enough fuel storage to run for several days, and some might not have tested their backup generators in a while anyway!

There is very little spare generating capacity left in the UK's power grid at times of peak demand, yet the total load continues to rise and fossil fuel power stations are being closed without reliable 24/7 replacements being online...

H
User avatar
Hugh Robjohns
Moderator
Posts: 24818
Joined: Fri Jul 25, 2003 12:00 am
Location: Worcestershire, UK
Technical Editor, Sound On Sound

Re: Well, yeah, again, electric shocks from mics !!

Postby Wonks » Sat Sep 07, 2019 2:48 pm

And more circuit loading due to the switchover to electric cars.
User avatar
Wonks
Jedi Poster
Posts: 9753
Joined: Thu May 29, 2003 12:00 am
Location: Reading, UK
Correcting mistakes on the internet since 1853

Re: Well, yeah, again, electric shocks from mics !!

Postby ef37a » Sat Sep 07, 2019 3:52 pm

I blame a good deal of the shortfall in providing the baseload to the prejudice against nulear power.

Yes, there have been some serious accidents but overall I think the nuclear industry is safer than many. Even the great Chenobyll explosion killed many fewer than it could have done and fewer than is generally thought. The knock on effects also seem to be less serious than predicted.

From what I have seen and read of the Japanese disaster? They put the emergency cooling pumps in the wrong place!

All heavy technology is dangerous but I bet it will be a long time before the nuclear power death toll reaches that of two centuries of coal miners?

And if we never build any more reactors, what of nuclear medcine and research tools?

Dave.
ef37a
Jedi Poster
Posts: 10724
Joined: Mon May 29, 2006 12:00 am
Location: northampton uk

Re: Well, yeah, again, electric shocks from mics !!

Postby blinddrew » Sat Sep 07, 2019 6:18 pm

Won't be a problem for us post 31st october when we crash out without a deal, lose our membership of Euratom and suddenly discover we have no-one qualified to handle fissile material anymore... ;)
[/brexitrant]
User avatar
blinddrew
Jedi Poster
Posts: 8275
Joined: Sun Jul 05, 2015 12:00 am
Location: York
Ignore the post count, I have no idea what I'm doing...

Re: Well, yeah, again, electric shocks from mics !!

Postby Trevor Johnson » Sat Sep 07, 2019 7:26 pm

And if we never build any more reactors, what of nuclear medcine and research tools?

Fortunately, that would not be affected, the Royal College of Radiologists have a Nuclear Medicine Specialty Training programme. I think it's often under appreciated how much exceptionally high quality medical research is conducted in the UK: the NiHR have a budget of just over £1 billion per year and I have been very lucky to be involved with NiHR backed research.

Talking of backup strategies, the most impressive I shall ever see was at Hartlepool Nuclear Power Station, nearly thirty years ago, with my father and half a dozen members of the local amateur radio group. After visiting the control room and standing on one of the two reactors, the final visit was to the backup generator shed. Well, I say shed, because it housed four Olympus jet turbines, (Concorde), that could get up to maximum output in just a few minutes. It must have been a bit noisy in there on test days!
Trevor Johnson
Regular
Posts: 211
Joined: Sat May 15, 2010 12:00 am

Re: Well, yeah, again, electric shocks from mics !!

Postby funky54 » Sat Sep 07, 2019 7:47 pm

Trevor Johnson wrote:
And if we never build any more reactors, what of nuclear medcine and research tools?

Fortunately, that would not be affected, the Royal College of Radiologists have a Nuclear Medicine Specialty Training programme. I think it's often under appreciated how much exceptionally high quality medical research is conducted in the UK: the NiHR have a budget of just over £1 billion per year and I have been very lucky to be involved with NiHR backed research.

Talking of backup strategies, the most impressive I shall ever see was at Hartlepool Nuclear Power Station, nearly thirty years ago, with my father and half a dozen members of the local amateur radio group. After visiting the control room and standing on one of the two reactors, the final visit was to the backup generator shed. Well, I say shed, because it housed four Olympus jet turbines, (Concorde), that could get up to maximum output in just a few minutes. It must have been a bit noisy in there on test days!

Are there microphones that shock people at these nuclear power stations? Do they use power conditioners?
funky54
Poster
Posts: 32
Joined: Mon Sep 02, 2019 3:57 am

Re: Well, yeah, again, electric shocks from mics !!

Postby Trevor Johnson » Sat Sep 07, 2019 8:41 pm

Are there microphones that shock people at these nuclear power stations? Do they use power conditioners?

There are microphones in the control room and in use for the mobile reactor teams.

Asking the director of a nuclear power station about power conditioning might seem a little insensitive! And I would hate to hurt anyone's feelings.
Trevor Johnson
Regular
Posts: 211
Joined: Sat May 15, 2010 12:00 am

Re: Well, yeah, again, electric shocks from mics !!

Postby Hugh Robjohns » Sat Sep 07, 2019 8:45 pm

:lol:
User avatar
Hugh Robjohns
Moderator
Posts: 24818
Joined: Fri Jul 25, 2003 12:00 am
Location: Worcestershire, UK
Technical Editor, Sound On Sound

Re: Well, yeah, again, electric shocks from mics !!

Postby funky54 » Sat Sep 07, 2019 11:06 pm

Trevor Johnson wrote:
Are there microphones that shock people at these nuclear power stations? Do they use power conditioners?

There are microphones in the control room and in use for the mobile reactor teams.

Asking the director of a nuclear power station about power conditioning might seem a little insensitive! And I would hate to hurt anyone's feelings.
Yeah.. don’t want the guy to go nuclear or anything. Some people really blow up.
funky54
Poster
Posts: 32
Joined: Mon Sep 02, 2019 3:57 am

Re: Well, yeah, again, electric shocks from mics !!

Postby MOF » Sun Sep 08, 2019 3:02 am

There are microphones in the control room and in use for the mobile reactor teams.

So long as there aren’t any wannabe guitar wielding technicians there they should be OK.
If there are their Amps will go to 12. :D
MOF
Regular
Posts: 440
Joined: Thu Mar 06, 2003 1:00 am
Location: United Kingdom

Re: Well, yeah, again, electric shocks from mics !!

Postby Hugh Robjohns » Sun Sep 08, 2019 11:25 am

funky54 wrote:Where I have noticed them really making a difference is in very old homes.... I also have noticed it cleaning up the sound at some outdoor events where the power was sketchy and from lots of extension chords...

Ah, okay. Yes... as I said earlier, there are mains supplies, and then there are mains supplies.

You're describing situations where the mains supply is likely to be significantly less than ideal, probably with poor ground referencing. In situations like that transformer-based 'power conditioners' can be very helpful. Perhaps that situation is more commonplace in the US...

Thankfully, it's rare here in the UK and hence there is rarely a need or benefit to using simple low-budget 'power conditioners'.

H
User avatar
Hugh Robjohns
Moderator
Posts: 24818
Joined: Fri Jul 25, 2003 12:00 am
Location: Worcestershire, UK
Technical Editor, Sound On Sound

Re: Well, yeah, again, electric shocks from mics !!

Postby funky54 » Sun Sep 08, 2019 12:52 pm

Hugh Robjohns wrote:
funky54 wrote:Where I have noticed them really making a difference is in very old homes.... I also have noticed it cleaning up the sound at some outdoor events where the power was sketchy and from lots of extension chords...

Ah, okay. Yes... as I said earlier, there are mains supplies, and then there are mains supplies.

You're describing situations where the mains supply is likely to be significantly less than ideal, probably with poor ground referencing. In situations like that transformer-based 'power conditioners' can be very helpful. Perhaps that situation is more commonplace in the US...

Thankfully, it's rare here in the UK and hence there is rarely a need or benefit to using simple low-budget 'power conditioners'.

H

It’s common in small town USA. Old sections of very old cities. Of course it’s not common in new big cities or new communities. Anywhere there are buildings built before the 50’s & 60’s could be suspect to poor power. Where I cut my teeth the majority of taverns and bars were built during Industrial booms from steel mills and factories. Most of those towns today are just where people sleep.

I’m not too sure about “cheap” power conditioners. Mine would be about $800 to $1000 each to replace. I know some guys have SurgeX or Furman gear for a few hundred, but those probably help too.
funky54
Poster
Posts: 32
Joined: Mon Sep 02, 2019 3:57 am

PreviousNext

Who is online

Users browsing this forum: MarkPAman, Wonks