HUMMM...is this a ground loop??? help please

K

kesterdevine

New member
I am working on a recording with a friend who has a Yamaha Motif ES. We are recording into a TASCAM FW-1082 interface to a PC running Cubase. When plugging the Motif into the interface, raising the input trim knob anywhere above 12 o'clock position creates a significant hum that increases as the trim is turned up. Without pushing the trim the signal is not hot enough. The hum is getting recorded to the track, so we can't just ignore it- we must eliminate it!


We have trouble shooted all the inputs/preamps on the FW-1082 and they work great (absolutely no noise) when using microphones and/or guitars, but the Motif is a problem.

We have tried changing cables, plugging into both the XLR, and TRS inputs, tried the HI-Z input, but the hummm remains. We have tried to eliminate anything that may be causing interference (modem,router etc..) Also, in the past I have recorded directly into a Yamaha AW16G from the Motif with no noise.

I suspect we may have a ground loop...although every outlet in the room is on the same curcuit. I don't have a lot of electrical or electronic background and could really use some advice about this.

Please if anyone has any ideas or suggestions as to how to solve this I would be very grateful.

Thanks!
 
Try plugging headphones into the Motif. Not into the headphone jack, but straight into each of the OUTPUT L/MONO, R plugs. Listen for the buzz there. This may reveal if the buzzing is actually coming from the keyboard circuits. If it is clean then start lifting grounds to see if the buzz going to the recorder changes.
 
Try plugging everything into powerstrips originating from the same wall plug. If that doesn't help get a ground lift plug and put it on the keyboard.
 
Thanks RawDepth and TexRoadkill for your responses. We have tried your suggestions and the HUMM remains. After doing some more research, it would seem that the Motif keyboards are somewhat infamous for the humming noise when connected to a recording device. Quite a nice/high end piece of gear to have such an annoying problem! But hopefully the use of a ground lift plug will do the trick. Thanks again for your help.
 
You must log in or register to reply here.
Back
Top