[doveman]

I've been experimenting with attaching the mic ripped off an old Logitech headset to my Samson SR-850 headphones but I'm not really happy with the sensitivity, with it needing to be right by my mouth to pick anything up. I also have to use my Realtek soundcard's boost of +20 or +30db, which also boosts the electrical noise level.
 
I've got a Creative Fatality headset and the mic on that is a bit better, with it not needing to be right in front of my mouth but I still have to use +20db boost.
 
So I'm looking around for a more sensitive, unidirectional, capsule that I can attach to an arm, made from metal or strong but bendable plastic and attached to my headphones. At present I'm using a bit of coathanger wire but that's not really suitable as it's too rigid and can't easily be bent to move the mic's position.
 
I'm not sure what impedance soundcard's need in a mic, nor what the sensitivity of my current one is likely to be. I don't want to spend a lot and wonder if any of these would be suitable?
http://www.maplin.co.uk/microphone-capsules-29594#specification
 
or maybe this would be better?
http://www.ebay.co.uk/itm/Panasonic-WM-61A-Electret-Condenser-MIC-Capsule-2PCS-/110573001571
 
or this, which is unidirectional (the above is omni) but less sensitive?
http://www.digikey.co.uk/product-detail/en/WM-55D103/P9897-ND/138179
 
Actually, it seems the mic on the Fatality has  Sensitivity: -40dBV/Pa http://uk.creative.com/p/headphones-headsets/creative-fatal1ty-gamer-headset, so the WM-55 would be less sensitive at [size=small]-54dB ±4dB @ 94dB SPL and so I'd still need to use the Mic Boost. The WM-61A is a bit more sensitive at -35dB[/size][size=small]±4dB but I don't know if that would make sufficient difference.[/size]

 

[doveman]

I was looking at the modmic http://www.modmic.com/pages/design-and-specsand it gives the specs as
high-fidelity 6mm electret capsule condenser microphone.
Operating Voltage: 1 to 10V
Max current at 2.0V: 500 µA

so where does it get the power it needs from, as I'm not aware that the mic socket on PCs sends out power?

Assuming they don't, would it mean that any electret condenser capsule will work, despite the lack of power from the mic socket?