Is ground loop between outputs possible?

[trhx]

I'm researching for a planned IEM rig to take to venues that have a house PA. I suspect this is a dumb question, but you know ...

Can a ground loop happen if the XLR outs are connected to house PA and 1/4" or headphone outs are connected to my IEM mixer? If yes, do you recommend an inline hum eliminator of some kind? If no, is that because Helix designed it that way, or is it just electronic design 101?

 

Thanks.

 

ETA: Of course, maybe this is exactly what the ground lift switch is for?

[Schmalle]

Assuming your IEM mixer also gets a signal from FOH there is a FOH -> IEM mixer -> Helix ground connection that could become a problem. Same if the IEM mixer has a 3 wire power cord (a cord with ground connection).

 

To break a ground loop in the 1/4" connection to your IEM mixer you need a either a DI box or a hum destroyer (assuming the IEM mixer doesn't have symmetrical inputs - if it does a special adapter cable is an option).

A good choice for a hum destroyer would be the Behringer HD400 or Pyle PHE300.

 

The ground lift switch can break a ground loop in the XLR connection if needed.

[trhx]

OK. No connection from the FOH mixer to the IEM mixer. All instrument and mic signals will be split before going out to the 2 mixers so the SE can concentrate on FOH and the band members can control our own monitor mixes. Any ground loop would potentially be from unisolated split outputs.

 

Sounds like the ground lift is what I need. Thanks.