There’s only one problem with the answer to the guitar electrocutions question. While the safety ground is certainly important to mind, there is no equivalent in the British electrical wiring. There is a different power distribution scheme there (and tmost of the rest of the world) than the US multi-grounded scheme. Since most of the electrocutions seem to have occurred in the UK, the reason for the problems were likely faulty wiring (or drug related experiments).
When posting a comment about a Staff Report, it is helpful to provide a link. In this case you are referring to Is playing the electric guitar dangerous?
It’s important to note that I did not specify what exactly the miswiring may have been, only that there was some problem that allowed line voltage to come into contact with the musicians. I mentioned the safety ground, since it applies to the US where the Reader (and thus the SDMB) is located.
Also, it is not true that a safety ground is never used in the UK. Here is a three-prong grounded mains plug used in parts of the UK and other countries.
Q.E.D.: from new member to guest contributor in less than six months.
We’re not worthy!
i was playing electric guitar in a friends low ceiling basement when some of the strings at the headstock(not trimed properly after being restrung) came into contact with a copper pipe above my head. it created a large ball of sparks but luckily i was not electrocuted.
Nevertheless your answer and advice was very US-specific, for instance that bit about the two-blade plug with one prong wider than the other. IMO that should have been made clear.
I’ve played places where the wiring in the wall was screwed up (the hot and cold wires wired in the oppisite of what it should be) and caused all kinds of problems. I accidently touched the front of my amp to a wall and scorched a black mark on the wall. Some higher end equipment has a swich where the hot wire and cold wires inside the amp or whatever can be reversed.
Speaking as a Brit, this is the only type of plug used all over the UK.
Julie
Point taken. But, naturally as a US citizen, I tend to write about what I know. And a good deal of the information presented is applicable, with minor modification, to most of the world. The article was intended more as a “Be Careful, You” type of thing, rather than a specific electrical how-to manual.
After a couple of fairly marginal episodes with musical instruments and electricity (one was a power lead with a broken earth - the bass amp would not switch off) I invested in a Residual Current Detector - this is always the first link in the power chain of my rig - I won’t hook up without it. An excellent safety device, and not very expensive.
Simon
here’s a handy tip for those of you rockin the clubs, and wanting to avoid a shock. Run your guitar through a DI box and then to your amp. Run a mic cable from the DI box to the club’s Mic Snake. This puts your guitar on the same grounding as the Club’s PA system and eliminates shock potential, and sometimes eliminates gutiar amp buzz in the process. IMPORTANT NOTE: make sure the soundguy knows NOT to use that channel in the mix, as it’ll sound crappy, and qute possible cause phase cancelation problems. the purpose of the DI use is merely to connect the grounds. and if the DI box has a “Ground Lift” switch, make sure it’s not engaged, otherwise the whole effort is wasted- you’ll be disconnecting the very connection that you are going out of your way to make!
I also travel (I am a soundguy for a living with various indie and major label bands) with a 12 foot pice of tiny wire with alligator clips on each end for the times when one guitar amp grounds different than the other- This does happen occasionally, and if the two guitarist happen to brush against one another while touching the strings of their guitars- zappo! not a big enough potential to seriously hurt, but it sure can be a surprise!
Q.E.D., congratulations on your first (I believe) column contribution. May it be the first of many.
Just wanted to say congrats on the Staff report. Good job. You have made a big impression on these boards, clearly. More please!
One problem with the use of a two-to-three-prong adaptor is that it assumes that the box the outlet is mounted in is grounded, even though a non-grounding outlet is installed.
This is not always the case- there are buildings where ancient knob and tube wiring is still in use and there is no grounding conductor connected to switch and outlet boxes.
If you’re going to use an adaptor to plug an amp with a three-prong plug into a two-prong outlet, get a grounded outlet tester or a voltohmmeter and learn how to use it to check for proper grounding.
A couple of other handy safety devices for the electric guitarist:
You can buy a portable ground fault circuit interrupter, which you plug into the outlet and into which your amp plugs. If the GFCI detects more than 5mA difference between the current flowing in the hot and neutral conductors (implying that the missing return current is flowing through someone’s body) it shuts off the power. If a GFCI repeatedly trips when your amp is plugged in and turned on, DON’T BYPASS IT- GET YOUR AMP AND EFFECTS CHECKED OUT BY A COMPETENT TECHNICIAN.
An isolation transformer- this is simply a 1:1 power transformer- 120VAC in, 120VAC out. Unlike the wall socket, neither side of the secondary of an iso trans is grounded, so that even if there is a direct line-to-chassis short in your amp, the chassis will not become “hot” with respect to grounded objects.
These gadgets are commonly used by TV technicians to work safely on “hot-chassis” TV sets, where one side of the AC line is directly connected to the internal metal structure of the set. They can be bought off the shelf at most electronics distributors serving the repair market- VIZ (formerly RCA) makes a nice line of them.
Back in my sound-guy days, I used a 3-section isolation transfomer (three independent outputs rated at 350VA each) to power the guitar and bass amps onstage. Not only did this provide protection against electric shock from a faulty amp, but I discovered that it was often helpful in getting rid of the annoying hums and buzzes that guitar rigs are prone to.
Finally, NEVER TRUST THE WIRING IN A BAR OR CLUB- IT MIGHT HAVE BEEN DONE BY A DRUNK. I’ve not only seen hot-neutral reverses in stage outlets in bars, I’ve encountered a club where the GROUND PIN on the stage outlets was hot with respect to earth ground and the PA ground, 240V circuits on receptacles rated only for 120V circuits- loads of wrong and dangerous stuff. The only reason we didn’t get anyone zapped or any equipment destroyed was that I checked the outlets for wring and voltage before trying to use them. If you’re playing at a place that’s too small to tie in your own properly wired and grounded power distribution system- make sure to check every outlet before you try to use it!
We have amended the Staff Report so that the stuff that’s U.S.-specific, specifies such.
Here’s a good website that will tell you how to 1) check for improperly wired outlets and 2) place a capacitor in your guitar circuit that will reduce the shock hazard to non-lethal levels. Read this article carefully because suggestion #2 will NOT protect you in all cases.
http://www.guitarnuts.com/safety/clubshock.html
My guitar playing days (electric of course) started in the mid-1960’s. Yes back in those ungrounded, unshielded, mimimal safety days you could get the occassional “surprise”. Who among us hasn’t received the “burnt lip” microphone shock? Also someone else mentioned about playing a guitar with untrimmed strings that came into contact with copper pipes. Well during the sixties, some people thought it was “cool” to play the guitar with ALL untrimmed strings. Besides the danger of injuring one or more of your fellow musicians’ eyes, another danger was having those string ends come into contact with a guitar player who is NOT on the same polarity you are. OUCH !!!
And anyone ever play a “pool party” back in those days? Let’s just say the “fun” is multiplied MANY times.
Well, at least some of us are still around to talk about those “safety last” days !!
The best way is to use a radio link from guitar to amp.They are not that expensive when you consider the cost of other instruments, and it saves a fortune in replacing faulty leads.
Radio mikes do thesame for front persons.
It is not uncommon for guitarists and vocalists to disconnect the amplifer earth to reduce the system hum which can be intrusive.
Guitarists can reduce the earth loop hum by using humbucker pick-ups although you don’t quite get the sound that you may want compared to your single pickup, especially when overdriving.
>But, naturally as a US citizen, I tend to write about what I know.
Naturally. But you cannot go on to assume that 1/ everyone who reads it knows you are a US citizen, and makes allowance for that, and 2/ everone who reads it is themselves a US citizen.
This site, like much of the rest of the internet, is read around the world and IMO you have to write your column accordingly.
As Dex stated, the report has been amended to reflect this. The change should appear within the next day or two.
When I was a young boy, I had an experience with a really electric guitar. This was years before I started playing guitar myself. Some friends and I were lured by a couple teenagers into trying to retrieve a penny from beneath the strings of an electric guitar.
The guitar was laid flat on the ground, and the penny was placed on the face of the guitar, between the pickups and under the strings. The teenagers told us “if you can get the penny, you can keep it”. Of course, we were all young enough that the idea of a free penny was still tempting, so we all took turns trying to slide that penny out of there. Problem was, we got shocked every time we touched the strings! But we really wanted that penny, so we kept trying, and kept getting shocked.
It’s obvious to me now that those teenagers had rigged the guitar up to shock people. But for a few years afterward, I honestly believed that electric guitars strings were electrified - which explained to me why guitarists were always moving their fingers so fast! I was still a bit apprehensive when a few years later I actually played an electrc guitar for the first time 