Genelec 1029A noise problem when light switch on/off

[miroslav]

Lt. Bob is pulling your leg....he probably lives on a houseboat, hence no ground.

 

[witzendoz]

Lt. Bob is pulling your leg....he probably lives on a houseboat, hence no ground.

So it is a floating supply

BAck in the early years of wiring they would often not connect an earth to power points in the bedrooms and lounge rooms, this is because they could not see how you could be grounded and get a shock in these rooms, I actually had an old house once that had no grounds in the bedrooms. The kitchens and bathrooms would have a ground as you can become grounded when you touch a tap or water going down a drain.

Nowadays every power point should have a ground connected.

Alan.

 

[Lt. Bob]

You mean your outlets don't have grounds. If the wall box is grounded then you might be able to use one of those adapters with the wall plate screw going through the tab and have proper protection. Otherwise the "correct" thing to do is have the wiring updated to modern standards. I do understand the resistance to spending money, but in this context I can only recommend doing it right.

So, if you did get electrocuted how would I collect?

dude ..... there are millions and millions and millions of homes in the US that still have two pronged outlets with no grounds.
I have NEVER lived in a house with three prong outlets in my entire life except the very last house my parents had for a few years before I moved out in 1970.
Every single house my wife and I have lived in was two prong outlets including the 1950's house we live in today.

Further, people use those three to two prong adapters millions of times every single day.
Every hardware store in the country has shelves with a hundred of those things sitting there for people to buy.


Look ...... first off ..... I have not said a single time that there is zero risk nor have I given any advice to anyone to do or not do anything.

ALL I have said is that ya'lls immediate "OMG OMG OMfucking GOD you're gonna die" reaction anytime anyone uses an adapter is ludicrously overblown and it is and it's easy to see that it is.

For example, your figure of 400 electrocutions a year, meant to show there is a real danger is 1. super misleading and 2. statistically insignificant.
A very quick google shows that about 100 of those are transmission line accidents. The rest are construction accidents and/or people digging where they shouldn't be and have absolutely nothing whatsoever to do with adapters or defeating grounds.
I'm sure there are some but the number is very small or I'd find some.

In fact, (I didn't spend a ton of time on this 'cause I don't care that much but I did do some searching) in fact I couldn't find a single electrocution associated with the things ya'll are going all 'nanny-state' over and I could only find three electrocutions in the last 30 years associated with guitar amps.
Sorry ...... but when you consider the billions of times that people have used those adapters in that time and the literally trillions of times people have plugged things into the wall in houses like mine with no grounds, the figure for electrocution due to that issue is essentially zero.

Statistically you are FAR more likely to get struck by lightening.
FAR more likely to choke to death on a sammich.
FAR far FAR more likely to die today in a car wreck.

Hell ..... a quick google showed 26 deaths from dogbites in a year and I can only find 3 cases of guitar amp deaths in 30 years.
Any of you guys ride motorcycles? .... Around 2700 dead a year.

Ya'lls concern is way overblown ....... period.

That's not saying that it can't happen. It can and I have to think it has even though I can't find any examples of it.
But in a society with 300 million people and millions of ungrounded homes and billions of three to two prong adapters out there, to not be able to find examples of the 'deadly consequences' of defeating ground means that it just about never happens.

A few other issues:
To our British and Australian friends .... you have 240v systems ...... obviously more dangerous than 110v. Your feelings and laws about it don't apply here.
To whoever suggested that I might go to jail if I had an adapter on something and someone got bit, hahahahaha ..... no chance whatsoever of that .... both because no one's gonna die from that in the first place but even if they did it would be an accident and nothing more. ZERO chance I'd go to jail for using a legal product that every single hardware store and Walmart sells every day.

For boulder who runs a sound company the issue is different. If he gets someone shocked, not even dead, just shocked ..... he could easily get sued damaging his company so he HAS to be sure no one gets bit even a little bit.

Finally ..... guys, I'm not some newb here that you have to explain basic concepts to ..... I absolutely know as much about this shit as any of you.
I have 45 years of doing sound fulltime for every single band I've ever played in for 7 nights a week for 45 years plus doing sound for other bands. I very likely have MORE gigs and experience under my belt than any of you.
At least as much at the very least.

Also I have my diploma in electronics/electrical repair on the wall saying that I know at least a little bit about this stuff.
Yes ..... that was 25 years ago but still .....

The ONLY areas ya'll know more than me about this stuff is in the latest new gear and processes. I pretty much quit doing sound other than for my own gigs about 6 years ago so if I needed to know something about the latest digital mixers and/or time alignment devices I'd ask boulder or moresound because I wouldn't know.
I don't know much about switching power supplies although if I needed to I could quickly learn. Just haven't had a need to. So when we get to D/A converters A/D converters ....... the very most modern gear ...... I haven't delved into it much.
But that's not what we're talking about here.

I'm NOT saying anything to anyone about what they should or shouldn't do ...... I'm just saying the 'OMG' reaction to defeating ground is ludicrously overblown and there's simply no way any of you can show any statistics that make it the super dangerous, deadly thing you're all asserting it is ..... it just isn't.
It CAN happen and no one should be careless about electricity but it's EXTREMELY rare.



.

 

[ecc83]

Evergreen Safety Council I found reported in uk 2010
28 deaths from "low voltage" electrocution. But perhaps we should be looking at the figure for "serious injury" from shock which is an astonishing 350,000.

Serious injury is defined as ..
"**Based on a survey of 4,032 adults in Great Britain aged 15+ who have personally experienced an electric shock that resulted in injury while at home or in the garden in the past twelve months including all those who experienced one or more of the following injuries: Severe pain, Skin burn without scarring, Bruising from a fall or severe muscular contraction, Temporary blindness, Heartbeat disturbance, Persistent pain or numbness, Higher blood pressure, Skin burn with scarring, Broken bone(s), Difficulty breathing.' "

There is never an excuse to lift an earth. Hum loops can always be fixed some other way and if they can't? It's only Rock &Roll.

Dave.

 

[bouldersoundguy]

I'm NOT saying anything to anyone about what they should or shouldn't do ...... I'm just saying the 'OMG' reaction to defeating ground is ludicrously overblown and there's simply no way any of you can show any statistics that make it the super dangerous, deadly thing you're all asserting it is ..... it just isn't.
It CAN happen and no one should be careless about electricity but it's EXTREMELY rare.

I did use capitals and unequivocal language, but I don't think that makes me Chicken Little. That message is for general consumption and may not apply to people with specific skills/training/education in electricity. When you don't know who might be reading it's best to be conservative.

 

[Lt. Bob]

I did use capitals and unequivocal language, but I don't think that makes me Chicken Little. That message is for general consumption and may not apply to people with specific skills/training/education in electricity. When you don't know who might be reading it's best to be conservative.

I understand that and let me repeat that I have not said a single time that everyone should go defeat their grounds or anything else like that.
I'm just saying that actual deaths from that act are actually very rare .......that's all I'm saying .... nothing more than that.

And I'm also only saying this with regards to the U.S. ...... I don't know the figures for 240v systems but I would imagine that injuries and deaths are much higher in those systems. To me 240v is a very different animal that I would be seriously careful around. 110v hurts but unless it gets you at just the right places it's unlikely to kill you.

An example:
One time a bass amp I was playing thru had the power switch knocked around in transit and put the live 110v to the chassis and thus, direct to the strings on my bass.
When my lips touched the mic *BAM* , I saw blue fire and it was like someone hit me in the face with a bat!
Knocked me to the floor it did!

When I got up I went to touch the large bass string to the mic stand and POW! .... it instantly melted thru!

So I had a worse case scenario where 110v went thru my heart from my left arm to my lips ....... it hurt like hell but I was fine.
I suppose had I had some underlying heart condition it could have killed me but it really didn't do anything other than knock me down.
Though that accident also had nothing to do with defeating ground, it does illustrate how mellow 110v can be ..... I bet had it been 240v I'd be dead.