newb question: PC mic doesn't work on my mixer?

[xyster]

I am a newb, so excuse this dumb question.

scenario:
I bought a mackie onyx mixer, used, to be used with some XLR lav mics I bought online. Currently the lav mics have not yet arrived, but I've been trying to play around with the mixer a bit still anyways, although the only non-usb microphones that I have here are cheap PC mics. (ie: 3.5mm, cost a few dollars at the store.)

If I hook up the line-out/speaker port from my computer to the input of the mixer, then hook up my amp to the mixer's out, things seem to work. ie: with the mixer's gain @~30%, the mixer's volume settles around 0db - fine. (The fact my PC outputs unbalanced stereo seems (i think) to be causing a small sound issue, but nothing important)

However, the problem that I'm having is that when I try to hook up a cheap PC mic to the same input port on the mixer, I get no sound, even with the gain set to max. nothing. I've tried multiple cheap PC mics, with mono and stereo plug 3.5mm adapters -- nothing. They work on my PC however just fine, with and without the soundcard's db boost option enabled.

It makes me feel like the mixer's preamp is not very sensitive at all. Is there like a pre-amp off/on button that I'm missing?

Question:
What on earth am I doing wrong, or what do I not understand?

 

[xyster]

Are PC microphones not compatible with mixers? An article I see online says that soundblaster PC mics have a 5-volt DC bias. Does the mixer not provide this 5-volts? I could turn on the mixer's phantom power, but isn't that 12-48V? I don't want to break anything....

Creative Labs has given the following specs for the Sound Blaster microphone input in their web site:

Input Type: Unbalanced Low Impedance
Input Sensitivity: Approx. -20dBV (100mV or 0.1Volt)
Input Impedance: 600 to 1500. (Ohms)
Input Connector: 3.5mm Miniplug (Stereo Jack)
Input Wiring: Audio on Tip, Ground on Sleeve, 5Volts DC Bias on Ring

http://www.epanorama.net/circuits/microphone_powering.html

I'm just assuming, but dynamic (typically professional) mics do not require power to work, but electret microphones (~5V) like PC multimedia mics, and condenser mics (<48V), do?
Taking this a step further, if I bought an electret lav mic and stripped it bare, then connected a 3.5mm plug to it, and then plugged it into my SoundCard - it should work? (since the PC speaker would be providing the 5V needed for it to work?) If this were the case, would buying just four soundcards for my PC, each with a mic input, be a cheap substitute for a dedicated mixer/preamp/AI ? Are non-selfpowered electret mics not compatible with my mackie mixer?

Im confused.

:S

 

[xyster]

I found a manual for a larger mackie mixer online that had this to say:

http://www.film-tech.com/warehouse/manuals/MACKIECR1604.pdf

I assume that my Mackie 1220 does not have these additional ports? Hence, not compatible with cheap electret mics, unless i provide power somehow to them? At least I know that not turning on the phantom power was a good idea. I'm not that retarded at least.

 

[oretez]

Electret mics, typically, are permanently biased and have their own on board power sources (and it is not necessarily true that hitting the phantom power will toast them it is, typically a good idea to not test the theory)

any mic will require some 'pre-amplification' to get it a level that will make it usable with general purpose mixers

if you are plugging the mic into the Mackies line level 1/4" inputs you simply lack that necessary first 'pre-amp' stage

to access the Mackies pre-amp you would need some type of adapter cable (3.5 mm to XLR) that should probably include some type of impedance transformer (Hz-Z computer mic to Lo-Z mixer input)

based on quality of most computer mics this is probably not worth time & $ unless you are looking for specific effect

 

[mshilarious]

Electret mics, typically, are permanently biased and have their own on board power sources (and it is not necessarily true that hitting the phantom power will toast them it is, typically a good idea to not test the theory)

PC mics do not have their own power source. They require the +5V power as described above. The lav mics should work into a PC if wired as described on the "Powering Microphones" page. You can make a simple 9V battery box as described on that page to run them.

 

[xyster]

thank you.