Microphone variable hum diff locations

[Guest Anonymous]

Hi,

I'm using a Sony MZ-N71- mini disc with a Sony ECM-MS907 condenser microphone (which has a battery in it) plugged into the mic in socket on the mini disc.

Crystal clear voice recording in one room of the house (while i'm holding the mic).

Anywhere else in the house there is a hum which varies from very loud in some locations to a quieter hum in other locations.

In the 'clear room' if I use a microphone stand to hold the mic, then if i'm very close to the mic.... no hum, i move back about 2 feet and the hum comes in.

Any ideas what could be causing this hum?

Any way around it if i have to record in a location where this hum kicks in?

Thanks,

Dave

[KJ_Palmer]

Anything that produces a strong magnetic and/or electric field would create a hum in a mic, and get worse the nearer you stand to it. It's basically feedback with the mic trying to record itself slightly out of phase. Something like a loudspeaker or TV set would give that effect. Is there anything like that in your "bad" room?.

Also, don't forget your body acts as a conductor and may pick up ambient electric fields which get relayed to your mic. If you wear insulating shoes and/or gloves this should alleviate the problem.

[Mark Nicholson]

I was having a lot of trouble with hum a few weeks ago but the hum disappeared. I am wondering if it had anything to do with those sun spots and solar storm we were experiencing.

Hmmmmmmmm.

[Guest Anonymous]

there are no loudspeakers in the room, no electronic equipment. There are ceiling lights which have dimmer controls, and socket outlets in the room, but nothing plugged in.

Funny thing, there was a powercut last week, and no hum during recording.

So i'm going to try switching off the fuseboard for the sockets and lights in that room and see what happens.

Not sure about sun spots, but did notice that when i poi9ned the mic towardsa a very big window the hum increased. However it also increased in many parts of the room too.

Dave