Live Sound Problems and Solutions

[UltimaWeapon]

Hi! This weekend we had a gig on a summer festival and oh boy we run into some problems and need some advice or any experience related to this.
So... where should i start. We all go digital (2x helix LT and 1 FM3) into a 12U rack unit where the routing goes like this:= Everything/Everyone goes into a Behringer MS8000 ultralink splitter which splits the signal to a regular patchbay and into a RCF M18 mixer. The MS 8000 and Helix have all the ground button ON. From the patchbay the FOH soundguy should get the exact copy of our sound. The RCF mixer is for our monitoring which goes out from the AUXes into the IEM systems. Also we use a Cymatic LP16 which also goes into the RCF M18 and into the patchbay, but this worked with no problem. The problem started when the FOH sound guy pulled the guitars UP and there was someking of HUM mixed with feedback layer or something. So we took out the Guitars from the splitter and went directly into the FOH guys mixing board without proper In ear monitoring ( We had to buy some time so we connected the Modelers second output into some Headrushes we brought) Atleast the click and cue worked through the IEM. But also our IEMs had this extra gallopping sound in the background. Wasnt sure if because of the electricity they provided through Diesel generators or something like that. Funny because this happened the first time ever that the guitars had this issue. Trying to figure our why or if there is some kind of shielding or isolation...
I know there might be many variables why is this happening, cable lenght, faulty splitter or patchbay, pickups... but sadly cant test this because in the rehearsal space everything works.

 

[c7spheres]

It could be anything no way to tell at this point, but if you weren't having issues before more than likely it's the venue's wiring.

 

[UltimaWeapon]

The only thing popped up my mind the next day that mabye the Splitter, Patchbay and the RCF m18 mixer are directly close to each other and the Mixer has a cooling fan which spins and can interfere with the guitar pickups?
Sadly cant test it out since we dont have the same setup like on the venue. This Friday we are going to another Summerfestival so we are seeking for any helpful tips.

 

[c7spheres]

Good power grounding and sheilding is everything. Hum Eliminators, JDI's Mid teir Furmans etc all go a long way, but will you be given time to deal with it if there's a problem? All you can do it try to make your own setup solid and pray for good power. A lot of times the power and the venues snake or board is a problem. If you always get there early you can tell what's happening before there's to much noise and before they even get around to hooking your own stuff up too. Fans lights everything interferes not to mention there's usually radio towers by anywhere you can jam for some reason. lol.

 

[GunpointMetal]

Could be anything. We have similar problems randomly with our splitter/IEM rig and it’s been exclusively at places with old electrical and portable stages. It’s usually our drum trigger that makes a bunch of noise, though. Keep extra DI boxes and 1/4”-XLR cables with you so you can run the DI out to FOH and the parallel out back to your splitter for IEMs.

 

[UltimaWeapon]

Could be anything. We have similar problems randomly with our splitter/IEM rig and it’s been exclusively at places with old electrical and portable stages. It’s usually our drum trigger that makes a bunch of noise, though. Keep extra DI boxes and 1/4”-XLR cables with you so you can run the DI out to FOH and the parallel out back to your splitter for IEMs.

Whats better passive or active DI-box? I have some Behringer passive DI-boxes at home. Might take them with me and let you know if helped.

 

[GunpointMetal]

Whats better passive or active DI-box? I have some Behringer passive DI-boxes at home. Might take them with me and let you know if helped.

We have cheap passive ones (Behringer, Pyle) and they’ve been fine for us. I think a transformer isolated splitter would probably work, too, but I wanted one with combo jacks and all I could find was Seismic audio.

 

[UltimaWeapon]

Update from last gig... everything went just fine. Even without DI boxes. This time the venue was connected to proper electricity (not diesel generators).
I did some switchups in the RACK tho. The RCF mixer went to ther opposite side of the rack which left some open space inbetween the splitters and IEMs.