Jobiebass Posted May 13, 2008 Share Posted May 13, 2008 sat in my back yard in the sun playing on the weekend, I noticed when I didnt touch the strings with my left hand and my right arm connected with the strings Id get an electric shock, ok its not all that bad, just felt like when you put your tounge on a 9v battery (come on, everyones tried it) havent had chance to see if it does this thru my ashdown yet, and I was using an extention lead into a crappy 10wat amp. But my bass is active so I was wondering if it had anything to do with that or something to do with the little amp and extention lead? Quote Link to comment Share on other sites More sharing options...
bremen Posted May 13, 2008 Share Posted May 13, 2008 [quote name='Jobiebass' post='197940' date='May 13 2008, 01:23 PM']sat in my back yard in the sun playing on the weekend, I noticed when I didnt touch the strings with my left hand and my right arm connected with the strings Id get an electric shock, ok its not all that bad, just felt like when you put your tounge on a 9v battery (come on, everyones tried it) havent had chance to see if it does this thru my ashdown yet, and I was using an extention lead into a crappy 10wat amp. But my bass is active so I was wondering if it had anything to do with that or something to do with the little amp and extention lead?[/quote] Certainly nothing to do with the bass being active. Check that the earth wire from the amp is securely fixed to the mains plug. Then check the extension. It's worth buying a cheap multimeter for this sort of thing, you can probably pick one up from Maplin for a fiver. If the earth between amp and plug is OK, get the house wiring checked. Quote Link to comment Share on other sites More sharing options...
Jobiebass Posted May 13, 2008 Author Share Posted May 13, 2008 [quote name='bremen' post='197946' date='May 13 2008, 01:30 PM']Certainly nothing to do with the bass being active. Check that the earth wire from the amp is securely fixed to the mains plug. Then check the extension. It's worth buying a cheap multimeter for this sort of thing, you can probably pick one up from Maplin for a fiver. If the earth between amp and plug is OK, get the house wiring checked.[/quote] awesome, as long as its nothing to do with my bass im happy. Ill get the other stuff checked though just to be safe Quote Link to comment Share on other sites More sharing options...
bnt Posted May 13, 2008 Share Posted May 13, 2008 (edited) The fact that you're out in the garden on an extension may also have something to do with it. Even if the bass is properly earthed, via the amp, well... it's a bit odd to explain but, basically, Earth is not necessarily Earth. The Earth point in your house might be at a different potential to the Earth you're sitting on in the garden, depending on e.g. power lines running nearby. Touching the house Earth to the local Earth could lead to a shock. If you have a multimeter, and you've verified that the amp and extensions are earthed (as noted by others), try measuring the AC voltage between the strings and the chair or ground. . But, I thought strings did not need to be earthed in an active bass? I know EMG tell you [b]not[/b] to re-attach the bridge earth wire when upgrading to their active pickups. If you were running an extension out to a shed, for example, you'd want to have a physical earth point in the ground under the shed, and not rely on the house earth... Edited May 13, 2008 by bnt Quote Link to comment Share on other sites More sharing options...
BOD2 Posted May 13, 2008 Share Posted May 13, 2008 Check that the extension lead has an earth wire. I've seen some older, orange extension leads that only had a live and neutral inside them. Quote Link to comment Share on other sites More sharing options...
bremen Posted May 13, 2008 Share Posted May 13, 2008 [quote name='bnt' post='197965' date='May 13 2008, 01:58 PM']The fact that you're out in the garden on an extension may also have something to do with it. Even if the bass is properly earthed, via the amp, well... it's a bit odd to explain but, basically, Earth is not necessarily Earth. The Earth point in your house might be at a different potential to the Earth you're sitting on in the garden, depending on e.g. power lines running nearby. Touching the house Earth to the local Earth could lead to a shock. But, I thought strings did not need to be earthed in an active bass? I know EMG tell you [b]not[/b] to re-attach the bridge earth wire when upgrading to their active pickups. If you were running an extension out to a shed, for example, you'd want to have a physical earth point in the ground under the shed, and not rely on the house earth...[/quote] No, if house earth isn't veryvery close to Earth earth, there's a problem. More likely, as Bod says, the extension lead. I borrowed a PA one time that had horrific mains hum - turned out one of the extension leads supplied had the N and the E wires reversed. Could have killed us all. I have a bass with EMG active pups and it makes little difference grounding the strings. They suggest leaving them floating so that if the amp becomes live then at least you won't get zapped via the strings, you have to touch the volume knob. Quote Link to comment Share on other sites More sharing options...
Jobiebass Posted May 13, 2008 Author Share Posted May 13, 2008 So passive needs the strings earthed, active not earthed. Gotcha, Im guessing its something to do with the Extention lead, it isnt great and im plugging it into my gym which is a seperate building away from the house. It used to be used as an office so the electrics were done properly, but I guess over time if they arnt being used...... Quote Link to comment Share on other sites More sharing options...
bremen Posted May 13, 2008 Share Posted May 13, 2008 [quote name='Jobiebass' post='197985' date='May 13 2008, 02:18 PM']So passive needs the strings earthed, active not earthed.[/quote] No, not necessarily. Some EMG pickups you can ground or not. A bass with a preamp is an active bass but it can have passive pickups, and then the strings do need to be grounded, to prevent hum and noise being picked up. But either way, you should not be getting shocks from any part of your bass. Quote Link to comment Share on other sites More sharing options...
BOD2 Posted May 13, 2008 Share Posted May 13, 2008 [quote name='bremen' post='197989' date='May 13 2008, 02:23 PM']But either way, you should not be getting shocks from any part of your bass.[/quote] +1 Can I just repeat this and add - do NOT be complacent about getting electric shocks from your gear. It is NOT normal and indicates that there is a problem somewhere which should be fixed as soon as possible. People have died from this type of thing ! Always use an [url="http://www.blue-room.org.uk/wiki/Residual_Current_Device"]RCD device[/url] when playing and always investigate any electric shocks no matter how small. Quote Link to comment Share on other sites More sharing options...
bnt Posted May 13, 2008 Share Posted May 13, 2008 (edited) [quote name='bremen' post='197975' date='May 13 2008, 02:09 PM']No, if house earth isn't veryvery close to Earth earth, there's a problem.[/quote] Sure, that too - there's no contradiction there, nor am I contradicting other advice given here e.g. use a RCD. My point is that, assuming the wiring is good, the amp is probably at house earth (because of the extension), while the garden is at garden earth, and the two might be different. Yes, I know it's weird, but it happens! I'm not saying that IS the problem here, but if you check all the earthing in the house and the amp, and the shocks still happen, this will be a possible explanation. An earth leakage detector would trip, but an RCD might not, because it detects whether there's leakage from the live wires, and in that case there isn't any. In an outdoor stage situation, everything needs to be grounded e.g. read [url="http://www.ratsound.com/cblog/archives/282-Day-402-June-29th-Munich-Show-Day-All-things-Are-Inter-Connected-or-Sometimes-Not-Part-2.html"]this[/url] for an example of when even grounding the stage and the generators wasn't enough, and a creative solution was needed. Edited May 13, 2008 by bnt Quote Link to comment Share on other sites More sharing options...
ahpook Posted May 13, 2008 Share Posted May 13, 2008 [quote name='BOD2' post='198000' date='May 13 2008, 02:36 PM']Always use an [url="http://www.blue-room.org.uk/wiki/Residual_Current_Device"]RCD device[/url] when playing and always investigate any electric shocks no matter how small.[/quote] plus the one... if you're using [i]any[/i] kind of mains electrical equipment outside and you're not using an RCD then you're...um...how should i put this...errr... [b]very unwise[/b] Quote Link to comment Share on other sites More sharing options...
Jobiebass Posted May 13, 2008 Author Share Posted May 13, 2008 it has a breaker etc, its all wired up properly, it used to have 4-5 desks and pc's in the gym when it was an office. im guessing its that socket as its on the inside of an outside wall which isnt protected well from the elements, plus the extention cable is questionable at best. never really thought about the health and safety side of it. Quote Link to comment Share on other sites More sharing options...
mr.sibs Posted May 14, 2008 Share Posted May 14, 2008 I noticed a similar problem the other day when using my pedals... i have a 6 way 9v daisy chain plugged into 3 pedals, and when i touched a screw on my midi keyboard, i got a small shock. I dont even know where to start with this, but i guess an rcd is a good one! I got a mains shock at college last week from a broken air conditioner, really not willing to risk that one again (wasn't my fault at all) Quote Link to comment Share on other sites More sharing options...
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