Using External Mic with Inspiron 8200 and fan noise

All built-in mikes tend to pick-up the noise and vibrations of the case into which they are built-in. The external mike you used provides no amplification. The farther from the notebook it is placed the clearer the sound will be. You can try a unidirectional external mike but it will pick-up the sound mainly from one direction only. That may not be enough in your case. You can also try a "boundary effect" microphone. It is a flat, credit card size mike which is supposed to be placed directly on the surface of the table. In this case the notebook should be placed on a soft foam mat. The last thing you could do, or maybe the first one, would be having the fans of the notebook replaced. Sincerely, Joseph

Carol,

In addition to Joseph's suggestions, I'd add that you should make sure 'mic boost' is turned on. Open Audio Properties (right click on the volume icon on the taskbar, or go through the control panel, Sound & Audio Devices). Select the Audio tab. Click on 'Volume' under 'Sound recording'.  Click on 'Advanced' under the microphone select box. Check the mic boost box. That turns on the mic preamplifier. I'm not sure if that is what you mean by amplifying the mic. Other than pre-amping, how much of a room the mic picks up is a function of its sensitivity.

Your Sony mic may require a voltage to operate. Some soundcards provide it and some don't. Below is the advice I offered to a court reporter who was looking for a mic. The battery box I mention might work with your Sony mic, but without knowing more about the mic I'm only speculating. The documentation that came with it should specify whether it requires voltage, and Dell or somebody here should be able to state whether your mic jack supplies that voltage.

Hope this helps,  Jim

I have an Inspiron 1100 .... I usually use condensor and dynamic mics run thru tube preamps, then into the line-in of an add on audio interface, but I fooled around with the 1100's built in hardware this morning and found a satisfactory solution. I used a mini disc mic and plugged it into a battery pack, then into the computer's mic jack. It worked great with 'mic boost' in the control panel either on or off. It clearly picked up every sound in the room, including a tic tic tic from a ceiling fan 15' away. When I took off the monitoring headphones, I had to strain to hear that fan noise. I doubt if my fancier equipment could pick up the whole room as well. There are electret and condensor mics which run off of an internal battery, and one of these could possibly give similar results but I don't know that for a fact.

The hardware came from The Sound Professionals, Inc, in '01. The mic is a little T shaped stereo mic SPSM-1, for $39 then, and the battery pack is the Delux Slimline Battery Module SP-SPSB-1, also $39 then. Here's where you can get this stuff:

http://www.soundprofessionals.com/cgi-bin/gold/category.cgi?category=130&template=mics.

About the hardware: minidisc mics require a voltage to work. When plugged into the recorder, the mic gets 2 or 3 volts from the mic jack, which is sufficient. The battery pack is a box about the size of a cigarette package which holds a 9 volt battery. The mic may be plugged into the pack whose higher voltage allows the mic to perform better, and allows it to be used with all recording equipment, not just a mini disc recorder. It is not a preamp, but the powered mic has plenty of output. The Slimline battery pack comes with an attached cable a couple of feet long, which would allow it to be placed outside of the computer case. I don't remember if the T mic is omni directional or not, but I have gotten great results placing it in the center of a circle of acoustic musicians. The dual mics point in opposite directions and pick up a wide field. In any case, Soundprofessionals has omnidirectionals available.

No, unfortunately Inspiron 8200 mic jack does not supply voltage to an external condenser (electret) microphone. In other words an external mic requires its own source of voltage. Joseph

Greetings, Joseph,

thanks for sharing that info with me, although I'm not sure it answered my question of whether 'computer mics' and minidisc mics are the same.

To ask it another way, what exactly is the amount of the voltage the computer mic jacks provide?

Jim

Hello Jim, theoretically the supply mic voltage is between 2.5 and 3 Volts. For example Averatec 3150 is supplied with 2.8V. My other laptop Inspiron 8200 is fully assembled and I was not able to measure the voltage at the moment. I will do it at the nearest convenience. Cordially, Joseph

Joseph,

Thanks so much. I am quite interested in this topic. Jim