The evil 2 prong plug.

[voodoostation]

Unless you're still living in 1976 or just like using ancient crap, every piece of modern electrical equipment sold in the U.S. with a real UL rating has a polarized plug, though I honestly think if we quit using polarized plugs we could maybe thin the herd and reduce the number of retreads promoting the use of two prong non polarized plugs. Just a thought.

 

[JKjr]

Bubblebath looks kinda like champagne, but the taste leaves a bit to be desired

Every Sunday morning I lay in the bathtub and make toast and jelly. It's OK though, my toaster has a 3 prong, and I can wash all the dishes without even getting up.

 

[teleman65]

My tech will not service any gear with 2 prongs unless part of the service includes installing a 3 prong. I've had some nasty shocks and think I'll go with the 3 prong.

 

[Tim Armstrong]

...there are techs out there that do not like to use them 3 prong plugs on amps for what ever the reason. I know one and woozy at the gear page knows one I would suspect there are certainly more out there. These folks also have been in business for a long time and are not afraid of giving this advice or worried about law suits so who is right and who is wrong hard to say as this is one of those continual debate issues. Jim

I'm pretty sure that you'll find one or two people in ANY field who hold an opinion that's different from the other 99% of their professional peers.

In the case of electronics, they're wrong, and their advice can kill you.

Cheers, Tim

 

[fakeocaster]

I'm pretty sure that you'll find one or two people in ANY field who hold an opinion that's different from the other 99% of their professional peers.

In the case of electronics, they're wrong, and their advice can kill you.

Cheers, Tim

+1

The laws governing free speech means theyre entitled to say what they like. The laws of physics mean theyre wrong

 

[RodeoTex]

My tech will not service any gear with 2 prongs unless part of the service includes installing a 3 prong. I've had some nasty shocks and think I'll go with the 3 prong.

Good for your tech, and you too.

With the old unpolarized plugs the chassis of the device or appliance was often 'hot' because the plug was in USD. Back in those days no one even noticed it much because they were standing on a wooden floor and not touching any real earth ground unless they leaned over and touched the sink or something.
I'm am electrician and cannot stand the sight of those old 2 prong unpolarized plugs. For the benefit of Eric Johnson I might put a 2 prong polarized cord on something but I'd still cringe. Modern structures are wired with true earth reference and I don't see any reason not to use it, especially with something that you are holding in your hands and sweating on.

I love the earlier story about paying the bass player to touch his mic and strings to test for a shock for a beer. That sounds like a true road story except my experience says that the drummer would have done it on a dare (every time) for nothing.

 

[surfoverb]

No offense, but just because Eric Johnson does something is not a license for you to do it to.

Never said it was...I was just responding to someone saying they don't know anybody that doesnt prefer 3 prong when clearly there are people.

EJ does it because 2 prongs sound better This is the same guy that can differentiate tones of variable battery brands.

Tim's diagnosis may very well be accurate.

 

[guitarzan13]

Eric Johnson is, well, crazy!

Cheers, Tim

Doesn't he also have the paint removed from under the pickguard?? He says that it allows the wood to "breath". He shoulda left it in the tree if he wanted it to breath.... strange dude, he is.

 

[robrohdeszudy]

I worked an entire career in electrical and electronics and have accrediation in each. I would absolutely never agree with anyone who refuses to install a hard wired ground to a guitar amp chassis.
If the power cable ground is properly installed, it will always be safe to touch the amp, guitar and strings. Period.
How can anyone, in this modern age, imagine a house or any other structure, wired with a "hot" ground?? If that were the case, sure you'd get a shock. I find it impossible to imagine receptacle wiring to be that screwed up. If in doubt, use a receptacle checker first. 2 wire power cords for guitar amps are archaic and dangerous. Do NOT bet your life on a 2 wire power cord.

BTW a 220k resistor in parallel with a .001 capacitor in the guitar is a "work around" and doesn't address the principle problem. I recommend leaving the instrument(s) as is and ensuring the amp is safe to touch.

+1!! More like +10, since I have most certainly played in venues with incorrect wiring. Sometimes reversed polarity, but very often no real ground. Definitely get a tester. --Rob

 

[robrohdeszudy]

Would you happen to know why?

Eric Johnson is the same guy who is positively convinced he can hear the difference if the guitar's cord is turned around and plugged in the other way.

Right. That's what I said too.

Not to bash the guy, but he's plainly delusional. I think he needs to be medicated. Hopefully before he gets electrocuted.
--Rob

 

[robrohdeszudy]

I'm pretty sure that you'll find one or two people in ANY field who hold an opinion that's different from the other 99% of their professional peers.

In the case of electronics, they're wrong, and their advice can kill you.

Cheers, Tim

Well put, Tim. --Rob

 

[Radspin]

My tech will always install a three-prong plug when repairing a vintage amp. If the customer insists on a two-prong, the tech makes him sign a waiver that the tech is not responsible if something shocking happens.

I have three-prong plugs in all my amps. I've been shocked one too many times while playing live (not recently though).

 

[DickensCPA]

I NEVER take anything electrical for granted. Certain additional precautions may not be foolproof, but I at least do everything possible to try and prevent disaster.

I got my degree and took the CPA, but my Dad has been an electric/plumbing contractor for 41 years. As a small child I was "free" labor. He made me get my elec and plumbing license as "something to fall back on." Glad he did. My brother will take over his business and I still take on the odd job with my brother for extra guitar money.

It's pretty common today that white is neutral, black is hot and bare is ground. It wasn't so long ago that it was up to the particular electrician whether he made black OR white hot. Either will work, just be consistent. Still a LOT of buildings out there with white as the hot wire. Imagine a club owner of an older building decides he wants to add an outlet himself. Reads a book and wires it as black=hot. Runs a feed line to the box, pays no attention to all the black wires on ground bar and runs his black into the breaker and his white and ground to ground bar. I went into that long boring piece just as an example of why to never take electricity for granted.

On the flip side, if you have a 3 prong plug and your outlets in an older home are only two prong, it's an easy fix. Buy a 3 prong recepticle and pick up some scrap wire. Usually bedrooms, living rooms, dens and so forth are 14g and kitchen, dining room, bathroom, garage and outside are 12g. 14g plug circuits will be in a 15A breaker and 12g in a 20A breaker. Take a scrap piece of white and hook to the green ground screw on new plug and the other end around the silver colored screws on the side. Silver colored side is neutral and polished brass is hot. Hook your existing wires in the wall to the appropriate hot and neutral side. You've essentially completed the same circuit in an older home with out a ground run.

 

[JimiBryant]

I would go three prong on any rig I planned to gig with - but, having
so many amps, I can't justify replacing power cords on all of 'em so I
make due with what I have and anytime a cord or plug starts to look
like it's ready to crumble then I'll replace it with a new heavy-duty
cord w/3-prong plug.

if one has a vintage amp and feels squishy about altering the cord,
just save the old one and you can change it back if you think you're
going to ever sell the amp.

electrocution happens rarely - regardless, it is not your friend.

of course one nice thing about 2-prong plugs is sometimes one can
get rid of 60-cycle hum by unplugging the amp and turning the plug
the other way round then plugging it back in!

 

[bradpdx]

Yea and there are still a lot of things out there that have 2 prong plugs that are not polarized too and they are modern stuff so not every one uses polarized plugs on their products.

That's because many objects don't need them - they are totally isolated from ground and don't care where the ground reference is. Harmless.

Amps are such a different thing. If they were always used in isolation from other electronics, it wouldn't matter so much. The danger of a 2-prong plugs stems from the likely fact that the player will be contacting other grounded or ungrounded electronics while using the amp. It's all relative in that respect.

The urgency is compounded by the fact that we still use ancient technology for passive guitar pickups that more or less requires us to use our bodies as ground planes to reduce noise. When you hold the strings of a stock Tele, your body is directly connected to the ground of the amp, acting as a big salt water pool of conductivity that absorbs ambient radiated electrical noise like a lighting rod. Until we all decide to use something like EMGs, this will continue to be the problem.

I cannot believe any responsible tech would refuse to install a 3-prong cord. Yes, you can make a 2-prong cord work if you are careful and observant - years ago I used to carry an electrician's tester in my pocket while setting up on stage - the risks are too great and utterly unnecessary. A 3-prong cord simply increases the probability that you are in fact PROPERLY grounded in the same way as the gear you are likely to touch.

All of us here who have experienced that fabulous "lip toaster" feeling when contacting a microphone that is 120VAC relative to you, please yell "AAGGGHHH!".

AAGGGHHH!

 

[Wally]

+another for the 3-prong. +another for wall outlet testers.
I am also not against 'fusing' the guitar ground with the cap/resistor rig.
Note: with humbuckers in a well shielded compartment, the ground to the strings may not be necessary.

 

[milocj]

On the flip side, if you have a 3 prong plug and your outlets in an older home are only two prong, it's an easy fix. Buy a 3 prong recepticle and pick up some scrap wire. Usually bedrooms, living rooms, dens and so forth are 14g and kitchen, dining room, bathroom, garage and outside are 12g. 14g plug circuits will be in a 15A breaker and 12g in a 20A breaker. Take a scrap piece of white and hook to the green ground screw on new plug and the other end around the silver colored screws on the side. Silver colored side is neutral and polished brass is hot. Hook your existing wires in the wall to the appropriate hot and neutral side. You've essentially completed the same circuit in an older home with out a ground run.

This will really work? Most of my living room and bed rooms are still two-prong and the wiring is not easily accessible to add the third wire or to run new Romex. If I just jumper the neutral to the ground prong of the receptacle will it also test correctly using those small plug in circuit testers? I've checked my outlets for polarity but it would be nice if I could actually have them grounded, too.

 

[emu!]

This will really work? Most of my living room and bed rooms are still two-prong and the wiring is not easily accessible to add the third wire or to run new Romex. If I just jumper the neutral to the ground prong of the receptacle will it also test correctly using those small plug in circuit testers? I've checked my outlets for polarity but it would be nice if I could actually have them grounded, too.

I am concerned on this one. Because there STILL IS NO EARTH GROUND. The round prong is supposed to be tied directly to an earthing rod outside the home. It will allow you to use a 3 prong plug, but doesn't really allow for the use of the earth gound in case of a circuit failure. Kinda like just sawing off the round prong with a hacksaw and plugging in an old socket.

 

[DickensCPA]

I am concerned on this one. Because there STILL IS NO EARTH GROUND. The round prong is supposed to be tied directly to an earthing rod outside the home. It will allow you to use a 3 prong plug, but doesn't really allow for the use of the earth gound in case of a circuit failure. Kinda like just sawing off the round prong with a hacksaw and plugging in an old socket.

Not quite exactly. First off you may remove your outlet and see a rolled up or nutted bare ground already in there, I have worked on some old remodel or addition jobs and found that. If not, your neutrals are still connected to the bar in your breaker box. The bar in your breaker box should have a #4 bare connected to an 8' ground rod driven into the ground.

Just because an older house doesn't have three prong outlets doesn't mean it's not grounded. On a newer house the neutral and ground go from two separate points on an outlet to the same point in the breaker box. By adding that jumper, you're just completing that same circuit.

Take a bedroom plug for example. 14-2 w ground wire going to a 15A breaker. Take your plug and wrap your bare ground around the green screw up top. Trim your white wire and put it in one of the holes in the back on the silver screw (neutral) side. Trim your black wire and put it in a hole on the polished brass screw (hot) side. 14g wire easily fits in those holes. I've been able to get 12g to fit rarely, but mostly you're gonna be actually wrapping those around the actual screws. Complete your circuit for that room, this means most all your plugs are going to have two sets of wires in them except the first and last plug. One of these two will be marked feed. I usually mark that stud with a sharpie. I take 14-2 w/ground and run from my feed plug to the breaker box. At the breaker box I run my 14-2 thru a grommet up top and trim and fold my wires neatly. Take my hot black and connect to the 15A breaker. Take my white neutral and bare ground and run to the same bar. That's how you wire a house with 3 prong plugs. Would you agree that plug has an earth ground?

Now if I did everything exactly the same as above, but only used 14-2 and no bare ground in the romex covering and hooked a jumper from a ground screw to a neutral, is that not the same circuit and earth grounded?

 

[Radspin]

All of us here who have experienced that fabulous "lip toaster" feeling when contacting a microphone that is 120VAC relative to you, please yell "AAGGGHHH!".

Count me in. It's not something you want to experience.