Here is a salutary tale...
Keith Relf, original singer for the yardbirds...
I know, not so 'rock and roll as way to go...found by his son dead on the floor...
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When ever I hear of people thinking, hmmm, I'll just wire this thing up to the wall I worry you know. Oh I know, "you'd have to be an idiot to..." well, we have all done something of that ilk, even the best of us and in some cases we might have built a time bomb that wont get us but some guy you sold it too that is not 'wireless' or a child...
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Now. down here in Oz they have a concerted campaign to have most places wired with 'safety switches'...I do not know what you may know them as over there...
www.justice.qld.gov.au/fair-and-safe-work/electrical-safety/for-householders-and-consumers/safety-switches/how-do-safety-switches-workAny new house and any old house or other premise where there is any significant wiring carried out, out here needs to have these things on the whole circuit.
Still, why not use a power strip like this...
www.arlec.com.au/viewProduct.aspx?productcode=FWP-R&catalogueID=2&parentCatalogueID=2 which has one in the plug and in most examples also 'surge protection' and such to protect the equipment too.
These things also work to test out if something is faulty because it will trigger it...
I got my click 4 plug ones for about $5 each and have used them all over the place. A normal powerboard plugged into this powerboard is also protected. If the power tool or equipment I am using is compromised, generally the powerboard will trigger and leave the rest of the house (or gig's) power still running. I have one in my amp that I use just in case other peoples places are dodgy, it will at least tell me if there is a fault.
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I've triggered them many times...hmmm...
I've also had a shock of a mic...not good...
No...a fuse won't blow...you will certainly be dead by the time it does. "Safety switches" are sensing faults such as currents going through to the ground presumably through you and shutting down in a matter of 'nano-seconds' instantly cutting off all power after it. It is completely different for a "fuse" which is not a 'safety device' at all...
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Do not be responsible for naively letting something out into the world that might be of danger to someone else...like cutting the grounds on mains wires and extension cords to stop a 'ground loop...consider a DI box, etc...
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Some pickups, like EMG's do not need nor want the strings to be 'grounded' but the way.
Do you always wear good shoes when playing or singing? Are you sure you are protected from perhaps a faulty PA sending a mains current through your mic to the floor regardless of the guitar?
If there is a problem with equipment of the way things are wired up in the building, a strange gig or rehearsal space, your equipment of something someone else drags in a SS might help identify it and at least save you, but don't persist or be smug about having such a thing if you know or suspect that you have or brought something in the world that is potentially lethal when someone else tries using it.
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Wireless, well sure why not...add even more layers of cover as well...but if the reason you are that concerned is because you have some suspicions about your equipment or something others will be using...and especially something you have built that will find it's way to others in it's lifetime without 'wireless'...then...well, wireless will not be enough!
There are problems with wireless too...ever heard a stray radio signal get into the channel...such as some trucker on a CB radio that can hear you yelling back abuse through a 100 watt rig...I have!!!!