jhammer619
Member
Hello all,
I'm posting this in the education section because I'm curious about the theory that goes into solving noise problems (EM in the air).
Here is my scenario: I am renting an old house, probably built in the 1930's. It has knob and tube wiring in the attic, and most of the outlets are ungrounded.
I set up a little recording studio in one of the rooms which basically consists of a computer, some audio interface equipment, and of course, microphones. I temporarily grounded the outlet that powers all the studio gear using an adapter and sending a wire to a copper pipe that already had another ground wire attached (I believe for CATV). It passed outlet tester test, but I'm not sure how great the ground really is.
I find single coil microphones (like the SM57 for those familiar) and electric guitars with single coil pickups have so much 60 cycle noise that they are unusable in this room. Condenser microphones seems to be immune. I am able to trace where the noise is most intense by moving the mic around, and of course it is toward the ceiling, where house electrical wiring is overhead.
I ran the whole system off battery and all the 60 cycle noise disappeared. I also tried running the system ungrounded, and I still have the exact same noise.
I've never had so much difficulty with house wiring noise before. All the equipment I'm using is the same or similar that I've used in other residences without any issues (several of equipment has SMPS). I'm just renting, and definitely won't live here for very long, so I realize I probably can't do anything to fix the noise.
However, I want to know: why is EM noise such a problem this time for me? People tell me "you need better grounding." It's obvious for safety reasons that this house needs a new electrical system, proper grounding/bonding/ground rods, etc. but it's not obvious to me how new wiring would help with this particular EM noise problem. If the circuits were re-ran with newer insulated wiring, would this "trap" the EM? What the physical mechanism that is allowing noise to be so rampant in this dwelling, but not be a problem with new wiring yet all else equal?
Thanks so much in advance for any theories!
I'm posting this in the education section because I'm curious about the theory that goes into solving noise problems (EM in the air).
Here is my scenario: I am renting an old house, probably built in the 1930's. It has knob and tube wiring in the attic, and most of the outlets are ungrounded.
I set up a little recording studio in one of the rooms which basically consists of a computer, some audio interface equipment, and of course, microphones. I temporarily grounded the outlet that powers all the studio gear using an adapter and sending a wire to a copper pipe that already had another ground wire attached (I believe for CATV). It passed outlet tester test, but I'm not sure how great the ground really is.
I find single coil microphones (like the SM57 for those familiar) and electric guitars with single coil pickups have so much 60 cycle noise that they are unusable in this room. Condenser microphones seems to be immune. I am able to trace where the noise is most intense by moving the mic around, and of course it is toward the ceiling, where house electrical wiring is overhead.
I ran the whole system off battery and all the 60 cycle noise disappeared. I also tried running the system ungrounded, and I still have the exact same noise.
I've never had so much difficulty with house wiring noise before. All the equipment I'm using is the same or similar that I've used in other residences without any issues (several of equipment has SMPS). I'm just renting, and definitely won't live here for very long, so I realize I probably can't do anything to fix the noise.
However, I want to know: why is EM noise such a problem this time for me? People tell me "you need better grounding." It's obvious for safety reasons that this house needs a new electrical system, proper grounding/bonding/ground rods, etc. but it's not obvious to me how new wiring would help with this particular EM noise problem. If the circuits were re-ran with newer insulated wiring, would this "trap" the EM? What the physical mechanism that is allowing noise to be so rampant in this dwelling, but not be a problem with new wiring yet all else equal?
Thanks so much in advance for any theories!