[SML] Rock Singer Electrocuted on Stage

[Dale Farmer]

On 11/27/2014 2:07 PM, Jerry Durand via Stagecraft wrote:
> Maybe grabbing a properly grounded microphone stand while holding a
> ground-lifted electric guitar that the performer personally modified?
>
> On 11/27/2014 11:01 AM, e-mail frank.wood95 via Stagecraft wrote:
>> All the same, I find it hard to see how a lethal electrocution can
>> happen with US 120V supplies. I suppose that a perspiring hand
>> clutching a microphone in a damp environment might do it. Entirely due
>> to my own carelessness, I have sometimes met our 230V supply. The only
>> effect it had was to make me remove my fingers sharply, and to speak
>> profane words.
>>
>>
A bunch of the early tube guitar style amplifiers were really cheaply 
made.   That distortion of the audio was a sign of the cheap components 
being overdriven.   Now they call it the classic guitar sound.    But 
who am I to call something bad?

  Anyway, they cheaped out on the shielding and insulation also, so they 
were very susceptible to ground loop hums.  SO many guitarists noticed 
that if the safety ground pin on the amplifier's power cord got broken 
off, it was much less likely to buzz and hum from ground loops.   So 
they broke off the ground pins, or always used a ground lift plug to 
make it sound better.     So far, so bad.

   Then, eventually, something in the amplifier broke.  Sometimes the 
brokeness left the amplifier still operating, but energized the chassis 
of the amplifier with mains current.   Unfortunately, one of the leads 
in the cord that connects the amplifier to the guitar is also connected 
to chassis ground, thus the metallic portions of the guitar are now 
carrying mains current, looking for a path to complete the circuit.   
Getting way more dangerous now.

   Clueless guitarist is playing away, sweaty hands and fingers in 
contact the energized parts of the guitar.   So now the system is armed 
and ready to kill.    Guitarist is playing away and steps up to the 
microphone and starts singing his heart out, and then he wants that 
close in sound and sings right into the microphone, lips touching the 
metal grill screen of the microphone.    Well, the microphone is 
grounded to the building via the cable and audio console.

    ZZZZZZAP!!    Full mains current runs from guitarist's hands up 
through his body and out his or her lips to the grounded microphone.   
Sometimes they get killed, sometimes knocked ass over teakettle, 
sometimes they get maimed or brain damaged, sometimes they just walk 
away with a memorable story.

   Alternate scenarios include stepping in a puddle of conductive liquid 
on the stage, or touching another piece of gear that still has an intact 
ground conductor, or touching another band member that is holding a 
microphone.   One I read about was a priest stepping into a baptismal 
pool holding a microphone during the service, and a defective pool pump 
had energized the water.

Moral of the story.  Breaking off the ground pin on your gear is a 
really bad idea.  Mmkay?

    --Dale