Re: SHOCKING!

[Bill Long <LONGWJ@xxxxxxxxxxxxxxxxxxxxxxxxx>]

>Date: Thu, 23 Feb 1995 10:35:52 -0700 (MST)
>From: Kim Hansen <khansen@xxxxxxxxxxxxxxxxxxx>
>Subject: SHOCKING!
> 
[...]
>....Anyway, he had his live guitar still strapped to his chest, reached for
>my mike, and got a jolt/shock.  I thought it was pretty funny, but then I
>thought about it, and figured that it was probably static electricity rather
>than the mike casing actually being hot from the amp.  But if it is, should I
>worry about electrocution?

Yeah, the guys in the first rock band I was ever in thought this was pretty 
funny too.  I played harp, rhythm guitar, and trumpet.

>I wasn't getting any jolts from the mike the entire night, but when I was
>holding it, I reached over to the guitarist to get his attention, accidently
>made contact with a tuning knob, and zap!  Got a blast.  So is there a
>difference in electricity flowing through a guitarist and a harpist, or is it
>the transferrance of electricity from the amp to the mike?  I checked the
>mike to see if there were any exposed wires hitting the casing, but couldn't
>see any directly.
> 
>My hair is standing on end here,  any help is appreciated.

On a lot of amps (my old fender bassman anyway) there is a ground switch in 
back.  If it's set wrong then the ground of the instrument amp and the 
ground of the PA amp are not the same (ie. there exists a potential 
difference between the two "grounds") and if you close the circuit by 
bridging the gap with your body then *>ZAP<* you get a 110VAC (or some part 
thereof) shock.

You should probably take care not to try this standing in a bucket of salt 
water with bare feet...like any electrical shock, the conditions under 
which it occurs will determine how severe it is.  Just remember that a 
current above about 200miliamps (.2A) will probably be fatal.

Oh yeah, the guys in the band would sneak up behind me while I was 
distracted and flip the switch on my guitar amp...then the next time I 
would put the harp up to my mouth while dampening the strings with the 
other hand and the harp would touch the mic?#&*~!!!  YEOUCH!  The smell of 
singed lips :^(#)  Needless to say, I didn't let them get away with this 
little trick more than a couple of times (they did get me at a gig once tho)

If neither of the amps you are using has a ground switch then look for one 
that only has a two-pronged power plug.  If possible flip it over in the 
wall recepticle and hopefully the shock hazard will go away.  This is a 
good thing to check for before the gig starts...so you know you won't be 
making any soulful facial expressions as your epidermal layers are being 
fryed away

Hope this helps

Bill Long  >--  StarGazer