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Andrew B
03-01-2003, 12:43 PM
Is there any difference between computer headset microphones and ordinary microphones used with a pa system? And why does the computer microphone have a stereo plug on the lead? I am trying to use my computer headset mic that I got with Dragon Naturally Speaking on a pa system in a tour coach. But it doesn't work.

Thanks, Andrew

Graham L
03-01-2003, 01:01 PM
If it has a stereo plug, it probably has one side of the microphone element connected to both channels. If that plug is put into a mono jack, that could short out the signal, if the ground contact in the jack hits the middle contact of the plug :-(

You could try a stereo-mono adapter (but try it in the shop ... if you can get a clued up assistant interested).

Bazza
03-01-2003, 01:10 PM
Hi Andrew:

This is an interesting question, and one that is not generally understood.

As you may know, the common monaural mics used for PA's & recording purposes are generally dynamic types.

The typical computer mic as used for connecting to the soundcard, is very different. It is an electret mic which requires a small DC voltage to operate. This voltage is provided by the soundcard mic socket.

Although the computer mic is not a stereo mic, this explains why a stereo mini plug is needed for the mic connection.

The connections of this plug are:

Tip: monaural audio.
Ring: small DC voltage.
Barrell: Earth.

You will see this explains why your computer headset mic will not work for your PA system, without modification & provision of the DC volts.

It also explains why it's not good practice to connect stereo lineoutput cables, or dynamic mics into the soundcard mic socket.

Cheers.

Andrew B
03-01-2003, 01:19 PM
Bazza, Thanks for your reply. I guess I'll have to look for a dynamic headset mic. Cheers, Andrew

Bazza
03-01-2003, 08:28 PM
Fine Andrew, I guess thats the best ting to do. The Electret mics are excellent quality, & are used extensively for phones, cellphones, & handsfree arrangements.

For your information & other Press F1'ers, the following Shure Microphone site has information on the use of mics into soundcards.

http://www.shure.com/support/technotes/app-soundcard.html

Cheers..