RF interference and ground loops (v1)

A video tutorial on the causes and remedies of radio frequency interference and ground loop hum in the project and home recording studio

[arashandarmin]

Thank you for the reply, i have talked to the Pearlman manager and he said he never heard of this problem and he didn't reply to my further emails

I did send the mic back to the company where i bought from, they did a check up on it and they said there is no problem with the mic

I did a research and many people have the same problem with different mics and recently i found a american company who makes isolators for RFI problems

They called Jensen transformers

I am trying to contact them and find out if they could solve my problem with their equipment

Its very frustrating to have expensive gears knowing they only record radio interferences :(

[arashandarmin]

There is a headphone jack on my pre amp
Focusrite One thats how i monitor the mic

so everything else its turned off when i investigate even the lights and other things.

I use an Apple i mac with apogee symphony I/O and they are usually
Turned off when i troubleshoot as well

I also have changed the actual 7pin mic cable as well the XLR in and outs

[arashandarmin]

I receive radio waves when i hook up my pearl man tm1 mic into pre amp, its really bad you can actually hear the music from the radio! 

I have tested them in another location it works perfect.

I have tried changing the mic cables into star quad cables and bought a power conditioner and still having the same problem! 

it looks like the 7pin mic cable is acting like an antenna 

do you know how do i solve the problem???

Regards 

[arashandarmin]

Sorry yes when i play around with the cable interference start to drop out and there is a spot which is the worse place to put the cable because the radio gets very high and you could easily hear the music even in low gains

Do you think i should get the PSU checked?
I don't know anyone who deals with hand made microphones

I live in london

Regards

[arashandarmin]

Here is what pearlman experts told me just now

"One thing you could try is to clip out the shield connection on the cable at the mic side of the cable. It's the middle twisted wire. Just clip it out with a small pair of wire cutters. You must be very close to a transmitter somewhere.
Good luck... dp"


Do you think this will solve it?

[LanceCampeau]

Great introduction tutorial, I've referenced it in my video... thanks!

[Projectstudiohandbook]

Thanks for your comments Steve. Really good. We had forgotten to mention CRT interference, so thanks for reminding us.

[steve-]

Ive got a Dean VMNT angel of deth Dave Mustaine signature and a Zakk Wylde epiphone Les Paul bullseye. My amps are a recently retubed JCM 900 halfstack 1960 cab and a Fender frontman 2x12. All of my amps tried at ANY outlet have a horrible hum/buzz. I have turned off the power to my house, unplugged every electrical device, and even used a generator to power my amps, and I still get a horrible hum/buzz. BUT I have taken my amps to other places, and there is NO NOISE, BUZZ/ HUM. I had an electrician come to my house and check the ground to my box, and he had no idea why I was getting the noise. My guitars and my amps are fine at other places, and I do not have "dirty" power at my house. Is this RF interference??

[Mgenis]

So, my chain looks like this: guitar->usb audio interface -> pc(running guitar rig/bias/etc). In this case there is a lot of hum, but some noisegates can handle with it, but when i add a preamp beetween guitar and audio interface no gate can help.
Now, the question is - if it's the groundloop conflict and if a dibox may help solving this issue?
Many thanks anyways

[ElizaDay]

I'm having random frequency blips on my voiceover recordings. They're about 1 second in duration.  Any idea what it could be?  My setup is a macbook pro, sennheiser MK4, Scarlett 2i2 (previously had a different interface that did the same thing) and a mogami cable. 

[kalutstyle]

So how do we deal with radio interference ? Is there any solution ?