Shock off the Mic

[Mark]

Hi i done a gig the other day and halfway through the lead singer complained that he kept getting and electric shock of the mic. everyone eles was fine or i think it was. can anyone tell me what was going on, just hope it hasn;t damaged any of my gear.

[Jamie the Sound]

Hi Just read your comment about a shock off the mic. This worries me a little , and to my knowledge it steers towards an earth fault on either a piece of equipment ( back line combo) i.e if the singer was holding a guitar at the time he got the shock when he touched the mic. If this was the case, then it is potencially fatal and someone could be seriously injured or even die. On a lighter note, if the lead singer had no contact with any other piece of equipment whilst performing, other than the Mic, it could be just stattic electricity generated by his / her clothing- making a stattic discharging when the mic was touched. The rule of thumb, make sure all your gear and the bands gear is pat tested regularly ,before plugging together. Any earthing / voltage leaking faults will show up and can be rectified. Hope this helps. Be Safe .... Regards Jamie

[Jamie the Sound]

Hi Just read your comment about a shock off the mic. This worries me a little , and to my knowledge it steers towards an earth fault on either a piece of equipment ( back line combo) i.e if the singer was holding a guitar at the time he got the shock when he touched the mic. If this was the case, then it is potentially fatal and someone could be seriously injured or even die. On a lighter note, if the lead singer had no contact with any other piece of equipment whilst performing, other than the Mic, it could be just static electricity generated by his / her clothing- making a static discharging when the mic was touched. The rule of thumb, make sure all your gear and the bands gear is pat tested regularly ,before plugging together. Any earthing / voltage leaking faults will show up and can be rectified. Hope this helps. Be Safe .... Regards Jamie

[andy]

this generally is an earth problem somewhere either the backiline itself and, or a problem with the mains you are using to power the backline. best to get to the bottom of it because i know guitarists whos lips have touched the mic they have been throw 6 feet in the air and had there guitar strings melted to there hand

[j]

This is a comon problem in venues that are not perfesionally fitted. what happens is in a venue all the p.a and lighting and relevent gear is on the same phase, in venues there are usually 3 phases if the pa is conected to diffrent phases than you get mic shock as the current is not runnin unison this is dangerous and could kill. to buypass this in dodgy venues put a muff over the mic gril so ur singer never touches the metal grill.

[Mark]

Thanks for you comments, the singer was playing a guitar and after investigation one of the amps he was using was faulty discharging the eart current through the mike, fortunatly all our gear is regularly pat tested. for some reason the lead singer gets this regularly (shock off the mic) so im thinking its him thats damaging the amps quite a few times unexpectingly valves have blow. the P.A and backline power is fed of the same phase as i use the rubber box single phase distro and run everything off that.

[soundmanjim]

bloody guitar amps and those poxy iec plugs that go in the back; i have had loads of trouble with bands bring naff ones to gigs and then getting zapped. i always carry a set of tested iec leads and then use only our stage distro's and not the guitarists!!
If its not the plug he's using, he needs to get the amp checked over immediately!
One guy i had here always used the same mains distro, and when he left it here by accident i took it apart and the earth wasnt even connected!!!
also the neutral and live were arse about face.
If there's that bad a fault in the wiring then the trips should go in the mains; this guy was always throwing the trips!
I bought him a new one and told him not to change it EVER! He hasnt been zapped or had any problems since.

[John Bell]

When I supply and engineer the PA for other bands, I always only use my own tested power leads. I also often supply some of the back-line gear, as it is easier to share equipment with friends bands that you trust, so that the change around time is minimal and the levels are already set and you know that the gear is safe.
I also use a plug-type, 3 LED power tester, on the wall sockets that I use at venues. Although they may appear OK, sometimes they will fail under load, due to loose connections.
I also test all of the mic, patch and speaker leads prior to each gig and I am surprised at the amount of dodgy leads that I find over a period. I have now stopped using certain suppliers.

[Chris]

What Mic were you using??

[Mark]

SM 58 Beta mic for the lead singer and just sm 58 for the rest of the band.