Hissing Sound in the Background

[Jenny]

Hey guys.

I'm having trouble with my microphone when connected to my computer(s).


INFORMATION
1. AKG C 1000 S (Works Fine - I think)
2. Hissing sound in the background on nmy IMac (connected to Mic jack)
3. Hissing sound in the background on my Laptop (Dell)


Here is a clip of what my mic output sounds like. I got my friend to record it and put it on his site:
http://www.barrykirkey.com/fin13_(audio_file).wav


Do you guys know what might be happening here?


I'm definitely not a mic expert and would appreciate ANY help I can get!


Thanks for reading!
Jenny

[Soopafresh]

Could be several things, but it sounds like you might be overloading the input level (clipping)

Edit. Yup, you are. have a look.... See the flat tops? Ouchies.



He's "popping" the mic with "T" sounds. Same goes with "P" sounds.

You have to lower the strength of the signal that's coming into your computer from the mic.

AKG C 1000 S has a presence boost switch. Just for testing, turn it off.

The first half-second of the sample says a lot as well. Here it is, exaggerated and looped. You'll hear the telltale 60hz grounding hum. (Not the part that sounds like House Music, but the ringing drone sound that you'd also hear if you ever unplugged an electric guitar from an amp)

groundloop.mp3

The same clip viewed with a frequency analyzer:


Here's a pretty good practical article on eliminating/reducing ground loops. I see your mic can use a 9 volt battery for power. Using that instead of external AC "phantom" power might be something to try.

http://www.guitar9.com/studionine7.html

[Jenny]

Hi Soopafresh!

Thanks for the response.

The article you sent me was good! Just in the process of hammering that out!


I bet you my right foot that I'll be back to ask you questions though!


Jenny