So I've been doing studio work for a while now and I'm now moving to live work. I usually dealt with noise on instruments by attaching a wire to the bridge or any other place attached to the circuitry of the instrument or cable to mine or the player's skin. I know about instrument shielding and grounding and have a general idea about grounding but it's all still sorta magical nonsense to me. Now that I'm moving into live sound on a cheap mixer, the ground loop thing is getting on my nerves because there are alot of opposing opinions all over the place so I came here to ask for some help. Here's what I want to know. Anyone with knowledge of electricity and dealing with ground loops and such, I'd be very grateful were they to chime in because I'd like to know the science too, not just how to fix it but anyone, feel free to help, talk about your experiences and so on. I'm desperate.
So here goes:
1) Starting from the building's source of power and circuit breaker. I've heard that studios usually ask power companies for an isolated line to remediate 'dirty' power. Obviously this isn't always practical for someone doing live sound but I'd like to know what that's about. I also read about these devices called GFCIs that I think attach to circuit breakers and there are some that are shrunk and in a different form as to attach directly to an outlet. Do GFCIs in a circuit breaker help with ground loops?

2) At the outlet side of things, the outlet version of GFCIs, Power Conditioners with RFI and EMI filtering, 'Ebtech's Hum Canceller', what should we employ here when the buildings power quality is beyond control?

3) After the outlet, moving on to the mixer and audio cables and so on. DI boxes and hum eleminaters on everything? Pseudo balanced cables on some things? Shielded cables help right? Why are audio gear manufacturers so DUMB ABOUT WIRING. There's a compliance standard right? I feel like that's never followed. Found this white paper (a term for something that's well established and could be called a standard) on interconnection between audio gear. Showed all the wiring that should be employed and a sigh of relief came as years of confusion over gear and microphones that misbehaved with mixers.

4) Beyond all guitars being shielded, grounded and having working, noise free equipment (depending on their inherent designs ofcourse [noise cancelling bass pickups anyone? Glenn Fricker taught me that one]), if there's anything past this point that's important I may have missed, feel free to mention.

Thank you to anyone who even read this far whether you have advice, stories to give or don't.

 

I can't be of much help, except for when it comes to guitar/bass. I have a weird setup. I have a Mesa preamp going into a 1960 Motorola stereo el84 tube hi-fi amp as my power amp. But even before that I have always had noise issues. I took my first guitar and did star grounding with foil and disabled the tone pots. Still noise, and that's a humbucker. My main two guitars now are single coils and P90s. I tried a power conditioner, a grounded steel pickgaurd, diff grounding options in my rack. I hated the idea of a noise gate/suppressor. They always suck tone and do that stuttering thing as it's cutting off and sometimes kills your note halfway through. I had an old Rocktron Hush. I did some research and it was between a Fortin Zuul pedal and the ISP Decimator G-String. After tons of video reviews I felt like the Zuul was sucking tone, so I went ahead and bought the ISP. With shipping it was $250 US. Nothing has ever made such an impact on my sound. It uses downward expansion but also has some patent pending technology. It tracks the signal directly from the guitar with one input, and then has another in/out to be put in an effects loop after the gain stuff but before time based (reverb, delay, modulation). It is crystal clear with no tone loss. No glitchy artifacts as it smoothly decays. It doesn't kill your sustain, and then it gradually ramps smoothly down to being fully gated. It's using the direct input from the instrument to track attack and release. Dead quiet as soon as you stop. Ambient passages, cleans, gain from pedals or switching to gain channel on my preamp and you don't have to touch the settings. One knob. Sorry I couldn't be of more help in a practical way, but I am now sold on this product and am getting a wonderful sound with no noise. That won't help with dirty power, but guitar/bass tracking... I recommend it.

 

@ WhiteMidnightProductions

Use a dropline to isolate or trace the offending source, very easy to do.

If you need more info prvt msg me, i will be away for about a week so expect a delayed answer.

 

Last edited: Nov 11, 2019