# Microphone Input Doesn't Work



## yalamo (May 29, 2003)

I have Windows XP Home with an Intel D865GBF AAC25827-402 motherboard with on-board sound card. I can't get the microphone input to work (the sound output works fine). It probably never did. When I first got the PC I couldn't get sound from the microphone, but I assumed it was because of a bad microphone, and didn't let it bother me. Now that I know the microphone is OK and it's a year and a half later, and I need the microphone for internet telephony, the question is what to do.

When I use the microphone, I can hear the sound very, very faintly on the sound recorder, which leads me to suspect that the microphone preamp on the MB is bad. I have tried the microphone setup wizard, and the various microphone advance and boost buttons, but it doesn't help.

It seems to me that I have 3 choices:

1. Send the MB back to Intel for fixing or replacement (the MB has a 3 year warranty) but this means taking the PC apart and being without it for about 2 weeks, plus other unknown complications.

2. Buy and install a new sound card - this will mean figuring out how to disable the onboard sound card.

3. Get a USB microphone.

Choice (3) seems simplest, but most expensive. Does anyone have any comments or suggestions?


----------



## jimscreechy (Jan 7, 2005)

Fear not Yalamo, for all is not yet lost.

Firstly what type of Microphone are you useing with your system? You have said the mic is working so I assume you have used it with some other type of audio kit, (your new kareoke equipment which you sing those old ABBA tunes on perhaps!)

Generally the mics used with PC's are eletret microphones essentially they are a type of cacitance microphone and they require a power source. You can tell this because they have 3 pins on the 3.5mm jack plug. The tip of the plug the 'Tip' is the mic signal, the ring (the second connector) provides a positive power source from the motherboard, and the Sleve, (usually the largest and last connector is ground. 

The normal mics that you will get in studios and recording equipment tend to be dynamic mics which do not require a power source. They therefore tend to have only 2 connectors, the 'Tip' for mic signal and the 'ring' for ground. 
These dynamic mics that tend to resemble and afro on a stick, are not really suitable for pc use. In fact depending on the tolerances of the connectors they can sometimes short out the sleeve and ring terminals of the pc socket which can cause the effects you describe. I won't go into the merits of each type of microphone but suffice to say you should use a PC mic with your pc and it should have 3 connectors on the 3.5mm plug. you can get these from almost any pc shop for a next to nothing. 

Dont use the 2 pin type of mic in your pc unless you have an adaptor made for this purpose. Such adaptors are fairly easy to find and essentially disable the ring connector on the microphone so only the tip and ring are fed to it.


----------



## yalamo (May 29, 2003)

The reason I said the microphone works is because I took it and plugged it into another PC (my wife's laptop) and it worked, but not in my PC.

It's rather academic now anyway: I bought a Skype phone (USB connection) and it works very well. A Skype phone was a choice I didn't mention in my post. Didn't know that there were such things then


----------



## jimscreechy (Jan 7, 2005)

Splendid!


----------

