Oh MAN! Please, please, PLEASE do
NOT use one of those adapters. They are unsafe and illegal, as per the National Electrical Code. Not that they'll cart you off in cuffs, but if someone gets zapped they'll be looking for the guy who plugged that thing in.
If you must lift the
ground on your
system it should be a last ditch effort and there are safe ways to do it. If there's no other way, then you can use a
GFCI (
Ground Fault
Circuit Interrupter). And you'll have to use one at each location you want to lift the
ground, amp racks, mix, pit, all of em.
You can buy heavy duty, construction rated
GFCI adapters and cut the
ground pins off of them. That's acceptable. Another option is to change the regular duplex outlets that your gear plugs into to
GFCI outlets and not hook up the
ground wire. But you
must use the "No Equipment
Ground" stickers that come with the outlets. And lastly, you can
build a little device on the cheap for just a simple spot
ground lift of a single device like a guitar amp or
console. Get a
cord from a hair dryer or similar appliance that has
GFCI protection included, cut it off and install a three prong recepticle on the other end.
GFCI is the
ONLY safe and legal way to lift the equipment
ground. If you don't get it, don't do it. Talk to someone who does get it. Read my post in the "What Went Wrong" forum "The things you learn the hard way" and find out how 54 volts AC can accidentally get into someone's dental work if you're not careful about grounding.
And lastly, lifting the
ground via
GFCI's is the last thing you should do, becuase they tend to trip a lot and you have to stop what you're doing and go reset them. If there's hum in the
system, it quite likely comes from using unbablanced lines. If all the
channel inputs on your cosole are filled with XLRs then you should see a significant reduction in hum. If you need to get a couple devices on DIs to get
balanced signal then do it. If it turns out that your
power system is at fault, get the staff to fix it or get them to hire an electrician to fix it. And lastly, if the problem is not with faulty or incorrect wiring, it might just be dirty
power from large motors elswhere in the building. If that's the case you could have an electrician move the circuits that your audio plugs into to the other bus bar in the panel and see if that helps.
Just please, Please, PLEASE be safe!